Featured today are 10 more women who broke boundaries by their presence in physics. They lived from 1711 to 2000. While I again limited information to one paragraph, I tried to highlight how they got their start, what universities, family members, and scientists were supportive of them. For these women, without the support of fathers, mothers, husbands, and mentors (all male with one exception) their life in science would not have happened. While barriers are not as difficult today as they were at the times these women made their way, it is a testament to what can be done when families and scientists support each other. These women are an inspiration and I hope you look up more information for them. In addition, I’d love to hear who your favorite women in science are in the comments.
Laura Bassi (1711-78) lectured on science until a few hoursbefore her death. An Italian scientist of international fame and one of the first women physicists in western history, Dr. Bassi earned her doctorate in philosophy and science through public debate from the University of Bologna. The University of Bologna offered Dr. Bassi a position in an effort to be known as a leader in women’s education. Unfortunately, this forward step was not acceptable to much of the rest of the world’s academic community and required stipulations to Dr. Bassi teaching. However, she countered these limitations with determination and passion. Her appointment to full membership in the Bendettini Academics also deterred some naysayers of Dr. Bassi’s involvement in research and teaching. In order to further her career, she married. A married woman could achieve more than a single woman at that time. Her death in 1778 was unexpected, especially as she had participated in an Academy of Sciences lecture on a few hours before.
Margaret Eliza Maltby (1860-1944) was a recognized scientistand advocate for women in science.She overcame the education offered to women by taking extra courses in order to attend Oberlin College and receive a B.A. She studied with the Art Students’ League in New York City to explore her interest in art and then taught high school before enrolling as a “special student” at the Massachusetts Institute of Technology (MIT), receiving her B.S. Oberlin recognized this extra effort by awarding Dr. Maltby an M.S. She became a physics instructor at Wellesley College. She was encouraged in her graduate students by an AAUW fellowship to attend Göttingen University, which culminated in Dr. Maltby being the first American woman to receive a Ph.D. in physics from any German university. Dr. Maltby worked as an instructor, a researcher, and administrator in many universities and colleges in the U.S. and abroad. Her stature as a scientist was acknowledged with her entry in the first edition of AmericanMen of Science. She also was active in the AAUW, advocating for women to gain education and enter scientific fields. After her retirement from university life, she maintained her interest in the arts.
Irène Joliot-Curie (1897-1956) was a Nobel Prize Laureate for “artificial radioactivity.”Born to the woman every person thinks of as the epitome of a woman in science, Marie Curie, Irène had an extremely close relationship with her paternal grandfather. Her schooling was outside of the standard schooling type, her first years at home and her latter years in a science and math heavy co-operative school of Madame Curie’s colleagues. She received her Bachelor’s degree from the Collège Sévigné and went on to study at the Sorbonne. She received her doctorate in 1925 based on work with her mother at the Radium Institute of the Sorbonne. She married Frédéric Joliot, another research assistant of Madame Curie’s. Dr. Joliot-Curie continued her research, interrupted by a stint as Undersecretary of State for Scientific Research, one of the first high government posts to be offered to a woman. She worked as a professor for the Sorbonne and director of the Radium Institute, but was not admitted to the Academy of Sciences due to discrimination despite her work. She died, like her mother, of acute leukemia. Her scientific work was complemented by her love of physical activity and motherhood.
Katharine Burr Blodgett (1898-1979) was a woman with an amazing number of firsts. Born to a widow, she was a world citizen in her formative years, attended high school at a private school in New York City, won a scholarship to attend Bryn Mawr, and graduated second in her class there. She received her Master’s degree from the University of Chicago, then headed off to work with Nobel Laureate Irving Langmuir at General Electric (GE) and becoming the first woman research scientist there. She was able to work with Nobel Laureate Sir Ernest Rutherford and earn her Ph.D. from Cambridge University as the first woman to earn a doctorate from Cambridge. She returned to GE. During her career, she invented many applications and is credited with six patents. She achieved much when many women did not, but her work was de-valued in the media. She did earn recognition from her peers, including the ACS Garvan Medal, the Photographic Society of America Progress Medal, and a day named after her in her hometown of Schenectady, NY. In addition to her scientific life, she enjoyed gardening, civic engagement, acting, and “dart[ing] about Lake George in a fast motor boat.”
Astrophysicist Charlotte Emma Moore Sitterly (1898-1990) was an authority on sun composition. She started her career as an excellent student with extracurricular interests, attending Swarthmore College to earn her B.A. Upon graduation, she accepted a position as a mathematics computer at Princeton University Observatory, one of the few employment opportunities available to science inclined women at the time. A stint at the Mount Wilson Observatory led to results published a 1928 monograph which was considered the authoritative work on the solar spectrum for four decades. She received her Ph.D. from the University of California, Berkeley in 1931. Her work earned her the Annie J. Cannon Prize, Silver and Gold Medals from the Department of Commerce, and several honorary doctorates in the U.S. and abroad. She was the first woman elected foreign associate by the Royal Astronomical Society of London. Her enthusiasm for her work continued until her death.
Nuclear Physicist Maria Goeppert-Mayer (1906-1972) was the second woman to win the physics Nobel. Her early education was public education for girls followed by a private school founded by suffragettes. Circumstances led Dr. Goeppert-Mayer to take her exiting exams a year early, passing them she attended the University of Göttingen for her college education in mathematics. She continued to study physics at the University of Göttingen, earning her Ph.D. in 1930. She also married that year. The couple moved to America in hopes of better career trajectory for Dr. Goeppert-Mayer. Finding a position was difficult. When she had her first child, she stayed home with her for one year, then returned to research. While her positions were always part-time and not well recognized, she grew a well-respected network of collaborators. This network led to work with Hans Jensen which won her the Nobel Prize, shared with Jensen. Her network also eventually led to a full professorship position after 20 years of volunteer work. During this time, her health began to fail. She persevered with her work, publishing her last paper in 1965. The American Physical Society established an award in her honor in1985.
Gertrude Scharff Goldhaber (1911-1998) was a respected researcher.She grew up in a time in Germany where girls were expected to become schoolteachers. She had a fascination with numbers, and eventually studied physics at the University of Munich, receiving her PhD in 1935. She fled Germany during the rise of the Nazis due to being Jewish, arriving in the United States and becoming a citizen in 1944. She had a wide involvement in the various National Laboratories studying nuclear physics. She also maintained several committee positions in the science community. She was also a strong advocate for women in the science community, forming a Women in Science group at Brookhaven National Lab and supporting other similar groups elsewhere. After her retirement from research, she continued interests in the history of science, outdoor activities, and art.
Physicist, Molecular Spectroscopist Leona Woods MarshallLibby (1919-1986)Leona Woods grew up on a farm and was known for her inexhaustible energy. She attained her B.S. in chemistry from the University of Chicago when she was only 19 years old, and earned her PhD 5 years later. She worked as the only woman and youngest member of the Chicago Metallurgical Laboratory, a secret war group led by Enrico Fermi who built the world’s first nuclear fission reactor during her graduate work. Dr. Woods’ expertise was essential to the undertaking. She married another member of her team. She hid her first pregnancy until 2 days before her son’s birth. She took one week off before returning to work. Childcare was provided by her mother and sometimes Fermi’s bodyguard, John Baudino. Dr. Marshall was encouraged by Fermi as a female physicist. In the late 1950s, Dr. Marshall was divorced from her husband, pursuing her own career. In the early 1960s, Dr. Marshall moved to Colorado to work and married Willard Libby. Her mind was always considering any number of problems from many angles. She worked up until her death and was honored posthumously for her work, along with Lise Meitner, Marie Curie, and Irene Joliot-Curie.
Chien-Shiung Wu (1912-1997) was a foremost experimental physicist of modern era. She was encouraged as a girl to pursue her schooling as far as possible. This led her to teaching training, which lacked science so she taught herself physics, chemistry, and mathematics. She graduated high school with the highest grades in her class, earning her a place at the National Central University in Nanjing. She taught and did research upon graduation, then moved to the United States to pursue graduate studies. She earned her Ph.D. from the University of California – Berkeley in 1940, four years after leaving China. She was known for her expertise in nuclear fission and was consulted by top scientists. Despite this, her gender and nationality hindered her finding appropriate employment due to discrimination on both accounts. She married and started a teaching career, although she missed research. Upon the recommendation of Ernest Lawrence, she received offers from several Ivy League schools who were not accepting female students at the time. She became Princeton’s first woman instructor at that time. She was offered several positions, including back in China, but chose to remain in the U.S. to raise her son. She was unable to return to China until 1973. She worked at Columbia for many decades and earned accolades for her work.
Xide Xie (1921-2000) is a woman in China who needs no introduction. Her early life involved much moving due to war and ill health, during which she taught herself English, calculus, and physics. She graduated in 1942 with a degree from Xiamen University. She moved to the United States to receive her master’s degree from Smith College in 1949 and her Ph.D. in physics from M.I.T. in 1951. She married in England and returned to China, despite the political climate. She taught and did research at the prestigious Fudan University. During the Cultural Revolution of 1966-76, she was detained, publicly humiliated, and endured breast cancer. After this upheaval, she returned to Fudan University, growing the physics department and achieving more esteemed positions in the University and government. She had also remained connected to her family, caring for her husband through lengthy illness. Her achievements were internationally recognized.
Benedettini Academics were a select group of scholars from the Academy of Sciences created and named for Pope Benedict XIV to conduct research and present it annually at Academy meetings. This appointment escalated the prestige of the scientist above that given by being a member of the Academy of Sciences.
American Association for University Women (AAUW): Margaret Maltby received the European Fellowship from the Association of Collegiate Alumnae, which became the AAUW. This fellowship was specifically intended to help American women pursue graduate studies to circumvent rules that did not allow women to enroll in coeducational universities or earn graduate degrees.
The Nobel Prize is an international award given in several fields. It is one of the most prestigious awards for scientists in the eyes of the public.
The Garvan Medal is an award from the American Chemical Society to recognize distinguished service to chemistry by women chemists.
The four basic categories of molecules for building life are carbohydrates, lipids, proteins, and nucleic acids.
Carbohydrates serve many purposes, from energy to structure to chemical communication, as monomers or polymers.
Lipids, which are hydrophobic, also have different purposes, including energy storage, structure, and signaling.
Proteins, made of amino acids in up to four structural levels, are involved in just about every process of life.
The nucleic acids DNA and RNA consist of four nucleotide building blocks, and each has different purposes.
The longer version
Life is so diverse and unwieldy, it may surprise you to learn that we can break it down into four basic categories of molecules. Possibly even more implausible is the fact that two of these categories of large molecules themselves break down into a surprisingly small number of building blocks. The proteins that make up all of the living things on this planet and ensure their appropriate structure and smooth function consist of only 20 different kinds of building blocks. Nucleic acids, specifically DNA, are even more basic: only four different kinds of molecules provide the materials to build the countless different genetic codes that translate into all the different walking, swimming, crawling, oozing, and/or photosynthesizing organisms that populate the third rock from the Sun.
Big Molecules with Small Building Blocks
The functional groups, assembled into building blocks on backbones of carbon atoms, can be bonded together to yield large molecules that we classify into four basic categories. These molecules, in many different permutations, are the basis for the diversity that we see among living things. They can consist of thousands of atoms, but only a handful of different kinds of atoms form them. It’s like building apartment buildings using a small selection of different materials: bricks, mortar, iron, glass, and wood. Arranged in different ways, these few materials can yield a huge variety of structures.
We encountered functional groups and the SPHONC in Chapter 3. These components form the four categories of molecules of life. These Big Four biological molecules are carbohydrates, lipids, proteins, and nucleic acids. They can have many roles, from giving an organism structure to being involved in one of the millions of processes of living. Let’s meet each category individually and discover the basic roles of each in the structure and function of life.
You have met carbohydrates before, whether you know it or not. We refer to them casually as “sugars,” molecules made of carbon, hydrogen, and oxygen. A sugar molecule has a carbon backbone, usually five or six carbons in the ones we’ll discuss here, but it can be as few as three. Sugar molecules can link together in pairs or in chains or branching “trees,” either for structure or energy storage.
When you look on a nutrition label, you’ll see reference to “sugars.” That term includes carbohydrates that provide energy, which we get from breaking the chemical bonds in a sugar called glucose. The “sugars” on a nutrition label also include those that give structure to a plant, which we call fiber. Both are important nutrients for people.
Sugars serve many purposes. They give crunch to the cell walls of a plant or the exoskeleton of a beetle and chemical energy to the marathon runner. When attached to other molecules, like proteins or fats, they aid in communication between cells. But before we get any further into their uses, let’s talk structure.
The sugars we encounter most in basic biology have their five or six carbons linked together in a ring. There’s no need to dive deep into organic chemistry, but there are a couple of essential things to know to interpret the standard representations of these molecules.
Check out the sugars depicted in the figure. The top-left molecule, glucose, has six carbons, which have been numbered. The sugar to its right is the same glucose, with all but one “C” removed. The other five carbons are still there but are inferred using the conventions of organic chemistry: Anywhere there is a corner, there’s a carbon unless otherwise indicated. It might be a good exercise for you to add in a “C” over each corner so that you gain a good understanding of this convention. You should end up adding in five carbon symbols; the sixth is already given because that is conventionally included when it occurs outside of the ring.
On the left is a glucose with all of its carbons indicated. They’re also numbered, which is important to understand now for information that comes later. On the right is the same molecule, glucose, without the carbons indicated (except for the sixth one). Wherever there is a corner, there is a carbon, unless otherwise indicated (as with the oxygen). On the bottom left is ribose, the sugar found in RNA. The sugar on the bottom right is deoxyribose. Note that at carbon 2 (*), the ribose and deoxyribose differ by a single oxygen.
The lower left sugar in the figure is a ribose. In this depiction, the carbons, except the one outside of the ring, have not been drawn in, and they are not numbered. This is the standard way sugars are presented in texts. Can you tell how many carbons there are in this sugar? Count the corners and don’t forget the one that’s already indicated!
If you said “five,” you are right. Ribose is a pentose (pent = five) and happens to be the sugar present in ribonucleic acid, or RNA. Think to yourself what the sugar might be in deoxyribonucleic acid, or DNA. If you thought, deoxyribose, you’d be right.
The fourth sugar given in the figure is a deoxyribose. In organic chemistry, it’s not enough to know that corners indicate carbons. Each carbon also has a specific number, which becomes important in discussions of nucleic acids. Luckily, we get to keep our carbon counting pretty simple in basic biology. To count carbons, you start with the carbon to the right of the non-carbon corner of the molecule. The deoxyribose or ribose always looks to me like a little cupcake with a cherry on top. The “cherry” is an oxygen. To the right of that oxygen, we start counting carbons, so that corner to the right of the “cherry” is the first carbon. Now, keep counting. Here’s a little test: What is hanging down from carbon 2 of the deoxyribose?
If you said a hydrogen (H), you are right! Now, compare the deoxyribose to the ribose. Do you see the difference in what hangs off of the carbon 2 of each sugar? You’ll see that the carbon 2 of ribose has an –OH, rather than an H. The reason the deoxyribose is called that is because the O on the second carbon of the ribose has been removed, leaving a “deoxyed” ribose. This tiny distinction between the sugars used in DNA and RNA is significant enough in biology that we use it to distinguish the two nucleic acids.
In fact, these subtle differences in sugars mean big differences for many biological molecules. Below, you’ll find a couple of ways that apparently small changes in a sugar molecule can mean big changes in what it does. These little changes make the difference between a delicious sugar cookie and the crunchy exoskeleton of a dung beetle.
Sugar and Fuel
A marathon runner keeps fuel on hand in the form of “carbs,” or sugars. These fuels provide the marathoner’s straining body with the energy it needs to keep the muscles pumping. When we take in sugar like this, it often comes in the form of glucose molecules attached together in a polymer called starch. We are especially equipped to start breaking off individual glucose molecules the minute we start chewing on a starch.
Double X Extra: A monomer is a building block (mono = one) and a polymer is a chain of monomers. With a few dozen monomers or building blocks, we get millions of different polymers. That may sound nutty until you think of the infinity of values that can be built using only the numbers 0 through 9 as building blocks or the intricate programming that is done using only a binary code of zeros and ones in different combinations.
Our bodies then can rapidly take the single molecules, or monomers, into cells and crack open the chemical bonds to transform the energy for use. The bonds of a sugar are packed with chemical energy that we capture to build a different kind of energy-containing molecule that our muscles access easily. Most species rely on this process of capturing energy from sugars and transforming it for specific purposes.
Polysaccharides: Fuel and Form
Plants use the Sun’s energy to make their own glucose, and starch is actually a plant’s way of storing up that sugar. Potatoes, for example, are quite good at packing away tons of glucose molecules and are known to dieticians as a “starchy” vegetable. The glucose molecules in starch are packed fairly closely together. A string of sugar molecules bonded together through dehydration synthesis, as they are in starch, is a polymer called a polysaccharide (poly = many; saccharide = sugar). When the monomers of the polysaccharide are released, as when our bodies break them up, the reaction that releases them is called hydrolysis.
Double X Extra: The specific reaction that hooks one monomer to another in a covalent bond is called dehydration synthesis because in making the bond–synthesizing the larger molecule–a molecule of water is removed (dehydration). The reverse is hydrolysis (hydro = water; lysis = breaking), which breaks the covalent bond by the addition of a molecule of water.
Although plants make their own glucose and animals acquire it by eating the plants, animals can also package away the glucose they eat for later use. Animals, including humans, store glucose in a polysaccharide called glycogen, which is more branched than starch. In us, we build this energy reserve primarily in the liver and access it when our glucose levels drop.
Whether starch or glycogen, the glucose molecules that are stored are bonded together so that all of the molecules are oriented the same way. If you view the sixth carbon of the glucose to be a “carbon flag,” you’ll see in the figure that all of the glucose molecules in starch are oriented with their carbon flags on the upper left.
The orientation of monomers of glucose in polysaccharides can make a big difference in the use of the polymer. The glucoses in the molecule on the top are all oriented “up” and form starch. The glucoses in the molecule on the bottom alternate orientation to form cellulose, which is quite different in its function from starch.
Storing up sugars for fuel and using them as fuel isn’t the end of the uses of sugar. In fact, sugars serve as structural molecules in a huge variety of organisms, including fungi, bacteria, plants, and insects.
The primary structural role of a sugar is as a component of the cell wall, giving the organism support against gravity. In plants, the familiar old glucose molecule serves as one building block of the plant cell wall, but with a catch: The molecules are oriented in an alternating up-down fashion. The resulting structural sugar is called cellulose.
That simple difference in orientation means the difference between a polysaccharide as fuel for us and a polysaccharide as structure. Insects take it step further with the polysaccharide that makes up their exoskeleton, or outer shell. Once again, the building block is glucose, arranged as it is in cellulose, in an alternating conformation. But in insects, each glucose has a little extra added on, a chemical group called an N-acetyl group. This addition of a single functional group alters the use of cellulose and turns it into a structural molecule that gives bugs that special crunchy sound when you accidentally…ahem…step on them.
These variations on the simple theme of a basic carbon-ring-as-building-block occur again and again in biological systems. In addition to serving roles in structure and as fuel, sugars also play a role in function. The attachment of subtly different sugar molecules to a protein or a lipid is one way cells communicate chemically with one another in refined, regulated interactions. It’s as though the cells talk with each other using a specialized, sugar-based vocabulary. Typically, cells display these sugary messages to the outside world, making them available to other cells that can recognize the molecular language.
Lipids: The Fatty Trifecta
Starch makes for good, accessible fuel, something that we immediately attack chemically and break up for quick energy. But fats are energy that we are supposed to bank away for a good long time and break out in times of deprivation. Like sugars, fats serve several purposes, including as a dense source of energy and as a universal structural component of cell membranes everywhere.
Fats: the Good, the Bad, the Neutral
Turn again to a nutrition label, and you’ll see a few references to fats, also known as lipids. (Fats are slightly less confusing that sugars in that they have only two names.) The label may break down fats into categories, including trans fats, saturated fats, unsaturated fats, and cholesterol. You may have learned that trans fats are “bad” and that there is good cholesterol and bad cholesterol, but what does it all mean?
Let’s start with what we mean when we say saturated fat. The question is, saturated with what? There is a specific kind of dietary fat call the triglyceride. As its name implies, it has a structural motif in which something is repeated three times. That something is a chain of carbons and hydrogens, hanging off in triplicate from a head made of glycerol, as the figure shows. Those three carbon-hydrogen chains, or fatty acids, are the “tri” in a triglyceride. Chains like this can be many carbons long.
Double X Extra: We call a fatty acid a fatty acid because it’s got a carboxylic acid attached to a fatty tail. A triglyceride consists of three of these fatty acids attached to a molecule called glycerol. Our dietary fat primarily consists of these triglycerides.
Triglycerides come in several forms. You may recall that carbon can form several different kinds of bonds, including single bonds, as with hydrogen, and double bonds, as with itself. A chain of carbon and hydrogens can have every single available carbon bond taken by a hydrogen in single covalent bond. This scenario of hydrogen saturation yields a saturated fat. The fat is saturated to its fullest with every covalent bond taken by hydrogens single bonded to the carbons.
Saturated fats have predictable characteristics. They lie flat easily and stick to each other, meaning that at room temperature, they form a dense solid. You will realize this if you find a little bit of fat on you to pinch. Does it feel pretty solid? That’s because animal fat is saturated fat. The fat on a steak is also solid at room temperature, and in fact, it takes a pretty high heat to loosen it up enough to become liquid. Animals are not the only organisms that produce saturated fat–avocados and coconuts also are known for their saturated fat content.
The top graphic above depicts a triglyceride with the glycerol, acid, and three hydrocarbon tails. The tails of this saturated fat, with every possible hydrogen space occupied, lie comparatively flat on one another, and this kind of fat is solid at room temperature. The fat on the bottom, however, is unsaturated, with bends or kinks wherever two carbons have double bonded, booting a couple of hydrogens and making this fat unsaturated, or lacking some hydrogens. Because of the space between the bumps, this fat is probably not solid at room temperature, but liquid.
You can probably now guess what an unsaturated fat is–one that has one or more hydrogens missing. Instead of single bonding with hydrogens at every available space, two or more carbons in an unsaturated fat chain will form a double bond with carbon, leaving no space for a hydrogen. Because some carbons in the chain share two pairs of electrons, they physically draw closer to one another than they do in a single bond. This tighter bonding result in a “kink” in the fatty acid chain.
In a fat with these kinks, the three fatty acids don’t lie as densely packed with each other as they do in a saturated fat. The kinks leave spaces between them. Thus, unsaturated fats are less dense than saturated fats and often will be liquid at room temperature. A good example of a liquid unsaturated fat at room temperature is canola oil.
A few decades ago, food scientists discovered that unsaturated fats could be resaturated or hydrogenated to behave more like saturated fats and have a longer shelf life. The process of hydrogenation–adding in hydrogens–yields trans fat. This kind of processed fat is now frowned upon and is being removed from many foods because of its associations with adverse health effects. If you check a food label and it lists among the ingredients “partially hydrogenated” oils, that can mean that the food contains trans fat.
Double X Extra: A triglyceride can have up to three different fatty acids attached to it. Canola oil, for example, consists primarily of oleic acid, linoleic acid, and linolenic acid, all of which are unsaturated fatty acids with 18 carbons in their chains.
Why do we take in fat anyway? Fat is a necessary nutrient for everything from our nervous systems to our circulatory health. It also, under appropriate conditions, is an excellent way to store up densely packaged energy for the times when stores are running low. We really can’t live very well without it.
Phospholipids: An Abundant Fat
You may have heard that oil and water don’t mix, and indeed, it is something you can observe for yourself. Drop a pat of butter–pure saturated fat–into a bowl of water and watch it just sit there. Even if you try mixing it with a spoon, it will just sit there. Now, drop a spoon of salt into the water and stir it a bit. The salt seems to vanish. You’ve just illustrated the difference between a water-fearing (hydrophobic) and a water-loving (hydrophilic) substance.
Generally speaking, compounds that have an unequal sharing of electrons (like ions or anything with a covalent bond between oxygen and hydrogen or nitrogen and hydrogen) will be hydrophilic. The reason is that a charge or an unequal electron sharing gives the molecule polarity that allows it to interact with water through hydrogen bonds. A fat, however, consists largely of hydrogen and carbon in those long chains. Carbon and hydrogen have roughly equivalent electronegativities, and their electron-sharing relationship is relatively nonpolar. Fat, lacking in polarity, doesn’t interact with water. As the butter demonstrated, it just sits there.
There is one exception to that little maxim about fat and water, and that exception is the phospholipid. This lipid has a special structure that makes it just right for the job it does: forming the membranes of cells. A phospholipid consists of a polar phosphate head–P and O don’t share equally–and a couple of nonpolar hydrocarbon tails, as the figure shows. If you look at the figure, you’ll see that one of the two tails has a little kick in it, thanks to a double bond between the two carbons there.
Phospholipids form a double layer and are the major structural components of cell membranes. Their bend, or kick, in one of the hydrocarbon tails helps ensure fluidity of the cell membrane. The molecules are bipolar, with hydrophilic heads for interacting with the internal and external watery environments of the cell and hydrophobic tails that help cell membranes behave as general security guards.
The kick and the bipolar (hydrophobic and hydrophilic) nature of the phospholipid make it the perfect molecule for building a cell membrane. A cell needs a watery outside to survive. It also needs a watery inside to survive. Thus, it must face the inside and outside worlds with something that interacts well with water. But it also must protect itself against unwanted intruders, providing a barrier that keeps unwanted things out and keeps necessary molecules in.
Phospholipids achieve it all. They assemble into a double layer around a cell but orient to allow interaction with the watery external and internal environments. On the layer facing the inside of the cell, the phospholipids orient their polar, hydrophilic heads to the watery inner environment and their tails away from it. On the layer to the outside of the cell, they do the same.
As the figure shows, the result is a double layer of phospholipids with each layer facing a polar, hydrophilic head to the watery environments. The tails of each layer face one another. They form a hydrophobic, fatty moat around a cell that serves as a general gatekeeper, much in the way that your skin does for you. Charged particles cannot simply slip across this fatty moat because they can’t interact with it. And to keep the fat fluid, one tail of each phospholipid has that little kick, giving the cell membrane a fluid, liquidy flow and keeping it from being solid and unforgiving at temperatures in which cells thrive.
Steroids: Here to Pump You Up?
Our final molecule in the lipid fatty trifecta is cholesterol. As you may have heard, there are a few different kinds of cholesterol, some of which we consider to be “good” and some of which is “bad.” The good cholesterol, high-density lipoprotein, or HDL, in part helps us out because it removes the bad cholesterol, low-density lipoprotein or LDL, from our blood. The presence of LDL is associated with inflammation of the lining of the blood vessels, which can lead to a variety of health problems.
But cholesterol has some other reasons for existing. One of its roles is in the maintenance of cell membrane fluidity. Cholesterol is inserted throughout the lipid bilayer and serves as a block to the fatty tails that might otherwise stick together and become a bit too solid.
Cholesterol’s other starring role as a lipid is as the starting molecule for a class of hormones we called steroids or steroid hormones. With a few snips here and additions there, cholesterol can be changed into the steroid hormones progesterone, testosterone, or estrogen. These molecules look quite similar, but they play very different roles in organisms. Testosterone, for example, generally masculinizes vertebrates (animals with backbones), while progesterone and estrogen play a role in regulating the ovulatory cycle.
Double X Extra: A hormone is a blood-borne signaling molecule. It can be lipid based, like testosterone, or short protein, like insulin.
As you progress through learning biology, one thing will become more and more clear: Most cells function primarily as protein factories. It may surprise you to learn that proteins, which we often talk about in terms of food intake, are the fundamental molecule of many of life’s processes. Enzymes, for example, form a single broad category of proteins, but there are millions of them, each one governing a small step in the molecular pathways that are required for living.
Levels of Structure
Amino acids are the building blocks of proteins. A few amino acids strung together is called a peptide, while many many peptides linked together form a polypeptide. When many amino acids strung together interact with each other to form a properly folded molecule, we call that molecule a protein.
For a string of amino acids to ultimately fold up into an active protein, they must first be assembled in the correct order. The code for their assembly lies in the DNA, but once that code has been read and the amino acid chain built, we call that simple, unfolded chain the primary structure of the protein.
This chain can consist of hundreds of amino acids that interact all along the sequence. Some amino acids are hydrophobic and some are hydrophilic. In this context, like interacts best with like, so the hydrophobic amino acids will interact with one another, and the hydrophilic amino acids will interact together. As these contacts occur along the string of molecules, different conformations will arise in different parts of the chain. We call these different conformations along the amino acid chain the protein’s secondary structure.
Once those interactions have occurred, the protein can fold into its final, or tertiary structure and be ready to serve as an active participant in cellular processes. To achieve the tertiary structure, the amino acid chain’s secondary interactions must usually be ongoing, and the pH, temperature, and salt balance must be just right to facilitate the folding. This tertiary folding takes place through interactions of the secondary structures along the different parts of the amino acid chain.
The final product is a properly folded protein. If we could see it with the naked eye, it might look a lot like a wadded up string of pearls, but that “wadded up” look is misleading. Protein folding is a carefully regulated process that is determined at its core by the amino acids in the chain: their hydrophobicity and hydrophilicity and how they interact together.
In many instances, however, a complete protein consists of more than one amino acid chain, and the complete protein has two or more interacting strings of amino acids. A good example is hemoglobin in red blood cells. Its job is to grab oxygen and deliver it to the body’s tissues. A complete hemoglobin protein consists of four separate amino acid chains all properly folded into their tertiary structures and interacting as a single unit. In cases like this involving two or more interacting amino acid chains, we say that the final protein has a quaternary structure. Some proteins can consist of as many as a dozen interacting chains, behaving as a single protein unit.
A Plethora of Purposes
What does a protein do? Let us count the ways. Really, that’s almost impossible because proteins do just about everything. Some of them tag things. Some of them destroy things. Some of them protect. Some mark cells as “self.” Some serve as structural materials, while others are highways or motors. They aid in communication, they operate as signaling molecules, they transfer molecules and cut them up, they interact with each other in complex, interrelated pathways to build things up and break things down. They regulate genes and package DNA, and they regulate and package each other.
As described above, proteins are the final folded arrangement of a string of amino acids. One way we obtain these building blocks for the millions of proteins our bodies make is through our diet. You may hear about foods that are high in protein or people eating high-protein diets to build muscle. When we take in those proteins, we can break them apart and use the amino acids that make them up to build proteins of our own.
How does a cell know which proteins to make? It has a code for building them, one that is especially guarded in a cellular vault in our cells called the nucleus. This code is deoxyribonucleic acid, or DNA. The cell makes a copy of this code and send it out to specialized structures that read it and build proteins based on what they read. As with any code, a typo–a mutation–can result in a message that doesn’t make as much sense. When the code gets changed, sometimes, the protein that the cell builds using that code will be changed, too.
Biohazard!The names associated with nucleic acids can be confusing because they all start with nucle-. It may seem obvious or easy now, but a brain freeze on a test could mix you up. You need to fix in your mind that the shorter term (10 letters, four syllables), nucleotide, refers to the smaller molecule, the three-part building block. The longer term (12 characters, including the space, and five syllables), nucleic acid, which is inherent in the names DNA and RNA, designates the big, long molecule.
DNA vs. RNA: A Matter of Structure
DNA and its nucleic acid cousin, ribonucleic acid, or RNA, are both made of the same kinds of building blocks. These building blocks are called nucleotides. Each nucleotide consists of three parts: a sugar (ribose for RNA and deoxyribose for DNA), a phosphate, and a nitrogenous base. In DNA, every nucleotide has identical sugars and phosphates, and in RNA, the sugar and phosphate are also the same for every nucleotide.
So what’s different? The nitrogenous bases. DNA has a set of four to use as its coding alphabet. These are the purines, adenine and guanine, and the pyrimidines, thymine and cytosine. The nucleotides are abbreviated by their initial letters as A, G, T, and C. From variations in the arrangement and number of these four molecules, all of the diversity of life arises. Just four different types of the nucleotide building blocks, and we have you, bacteria, wombats, and blue whales.
RNA is also basic at its core, consisting of only four different nucleotides. In fact, it uses three of the same nitrogenous bases as DNA–A, G, and C–but it substitutes a base called uracil (U) where DNA uses thymine. Uracil is a pyrimidine.
DNA vs. RNA: Function Wars
An interesting thing about the nitrogenous bases of the nucleotides is that they pair with each other, using hydrogen bonds, in a predictable way. An adenine will almost always bond with a thymine in DNA or a uracil in RNA, and cytosine and guanine will almost always bond with each other. This pairing capacity allows the cell to use a sequence of DNA and build either a new DNA sequence, using the old one as a template, or build an RNA sequence to make a copy of the DNA.
These two different uses of A-T/U and C-G base pairing serve two different purposes. DNA is copied into DNA usually when a cell is preparing to divide and needs two complete sets of DNA for the new cells. DNA is copied into RNA when the cell needs to send the code out of the vault so proteins can be built. The DNA stays safely where it belongs.
RNA is really a nucleic acid jack-of-all-trades. It not only serves as the copy of the DNA but also is the main component of the two types of cellular workers that read that copy and build proteins from it. At one point in this process, the three types of RNA come together in protein assembly to make sure the job is done right.
Leah Gerber is an Associate Professor of ecology at Arizona State University. Her research is motivated by a desire to connect academic pursuits in conservation science to decision tools and effective conservation solutions. This approach includes a solid grounding in natural history and primary data collection, quantitative methods and an appreciation for the interactions between humans and the environment. She is keenly aware of the need for the communication of scientific results to the public and to government and non-governmental agencies. This communication is essential for the translation of scientific results into tenable conservation solutions.
DXS: First, can you give me a quick overview of what your scientific background is and your current connection to science?
LG: I learned about ecology and environmental conservation as an undergraduate and quickly became motivated to do science that impacted the real world of conservation. Learning about the impacts of humans on nature was a wake-up call for me, and inspired me to channel my feeling of concern for the demise of nature in a positive way.
From there, I have walked the tightrope between science and policy. After getting my undergraduate degree in environmental biology, I wanted to do more than just the science. So I enrolled in a masters program at the University of Washington – an interdisciplinary program called Marine Affairs. It was a great experience, but I wanted to have more substance to my science background – I wanted to know how to do the science in addition to how to apply the science.
This compelled me to enter a PhD at the University of Washington, which was largely funded by NOAA. My thesis involved trying to figure out how to make decisions about endangered species – how to determine which were endangered and which were threatened. This was a perfect project given my interest in developing tools to solve problems. After finishing my PhD, I did a postdoc at the National Center for Ecological Analysis and Synthesis (NCEAS) and developed approaches for marine reserve design and endangered species recovery. I was at NCEAS for three years before starting on the tenure track at Arizona State University. I’ve been at ASU for about 10 years now.
A major theme in my work has remained constant – that is, how to use the information we are generating in the natural and social sciences to better manage our natural world. Pre-tenure I focused a lot more on doing the science, publishing in good journals, and hoping that it made its way into good policy. Now that I am midcareer, meaning that I have a good amount of papers and tenure, I am enjoying the opportunity to work with practitioners outside of academia. For instance, I just got off the phone with someone from National Geographic regarding my recent publicationon seafood health and sustainability. In that study, we performed an analysis regarding seafood in the context of health and sustainability, to answer simple questions like, what to order when out to sushi? How do we educate about health benefits and risks? We will be organizing a workshop to help restaurant chains, grocery stores, as well as environmental NGOs identify a path forward in informing consumers about healthy and sustainable seafood choices. As a tenured professor, I feel fortunate to have the opportunity to work at the science-policy interface and to give society some science that is truly applicable.
DXS: It is too bad that you have to wait until you are more established and have tenure to go out and engage with the public, because this type of thing is just so important!
LG: Yes, I agree. There isn’t a clear path in academia when it comes to public engagement. But in recent years I have felt optimistic – the landscape within academia is starting to change, and at ASU this change is noticeable. We have a fabulous president, Michael Crow, who has really transformed ASU from just another state institution to a leader in sustainability. Part of this is the establishment of the Global Institute for Sustainability, and one of Michael Crow’s mantras is “community embeddedness.” He is really on board with this type of thing and I have seen evidence of his commitment trickle down throughout the University. For instance, when I first arrived, I had to justify and explain why I was serving on these federal recovery teams for endangered species. Now I feel that there is no justification needed. Developing solutions is not only so important for society, but should also be a key aspect of what we do at Universities.
DXS: We were introduced by another fantastic science communicator, Liz Neeley, who you met at a communications workshop. Why is it important to take part in this type of training?
LG: I met the Fantastic and Fashionable Liz through the Leopold Leadership Program, offered through the Woods Institute for the Environment at Stanford University. The Leopold Leadership training was the best professional development experience of my career, and has made me a better translator and communicator of science to policy. Pre-Leopold, I had little training in communications, and there I was, in a teaching position where I taught hundreds students. I thought to myself, well, how do I do this? The Leopold experience has solidified my commitment to teaching students about communication and engaging in policy.
One development emerging from this training is a science communication symposium at the AAAS meeting. Elena Bennett and I are giving a talk on overcoming institutional barriers for community engagement, and we will address the issues head on. We put out a survey asking others if they faced institutional barriers, and how they might work to engage more.
DXS: What ways do you express yourself creatively that may not have a single thing to do with science?
LG: I have 2 young kids, a 3yo and a 7yo. Being a mom helps me keep it real - I love that I get to enjoy the awe of discovering the world with my girls. We just got a puppy this weekend and we are having fun dressing her up and painting her nails (only partly joking). Other things that I do that are creative – truthfully, I am uninteresting – I don’t bake bread or go to the opera. I just work and take care of my kids. I practice yoga for my own sanity and also love to work in the garden. Doing these things gives me a reason to pause and step off the treadmill of keeping up with everything.
DXS: Do you find that your scientific background informs the creativity you have with your kids or your yoga practice, even though what you do may not specifically be scientific?
LG: I think there is synergy with my science and my kids and my yoga practice in helping me to accept things and be mindful – but not in any conscious way. For instance, when doing my science, the type A person that I am, I have an inclination to keep pushing, pushing, pushing. My kids and my yoga help me to shift gears and accept that things are going to happen when they happen. I try to let the kids be kids, including the associated chaos, and accept that this is a snapshot in time that they will be little. Now I find joy in that chaos. Having kids and yoga gives me a little more perspective, and the knowledge that things aren’t lined up and neatly placed in a box. It rounds me out.
DXS: Are your kids are major influencers in your career?
LG: My first child, Gabriella, was born just after I submitted my application for tenure – so it was good timing. And I was able to slow down. I quickly realized that I wasn’t able to work a 60+hour week. Before kids, I lived to work. Now, I work to live. I absolutely love my job and I feel so lucky that I have a career that I believe in and that I am actually paid to do it – it’s not just a hobby. But having kids made me chill out a little. If I get a paper rejected, I can let it go instead of lamenting about it for weeks. It has made me healthier. I don’t necessarily know if it has had positive impact on my career – time will tell. While my publication rate may be slightly smaller, I think my work now has different dimensions, and greater depth.
I am still pretty passionate about my work, and my kids know what I do and are proud of it. They share it with their classmates, and take every opportunity to wax poetic about how their mom saves animals in the ocean. They also have a built in conservation effort – my 7YO gets irritated when she can’t find a compost bin, and her new thing is to only fill her cup half way because she will only drink a little bit of water.
DXS: When you decided to have children, did your colleagues view you differently? Did they consider that you were sending your career down the tubes or was it a supportive environment?
LG: I honestly had a really positive experience. I can’t think of any negative sentiments from my colleagues, and they were actually really supportive. For instance, when I was pregnant with my first daughter, ASU did not have a maternity leave policy. Before that, you would have to take sick leave. So my colleague worked within the parameters of the unit to give me maternity leave. And then with my second daughter, our new president had established a maternity policy.
The support of my colleagues at ASU has made me feel loyal to my institution. Normally, I am loyal to people and not institutions, but overall, the support has been fabulous. Of course, with having the kids in each case, I did decline a lot of invitations – some pretty significant ones – but I did not have a desire to drag a newborn to give a talk, especially when I was nursing. And it was hard for me to do this at times, especially given my career driven nature, and I had to learn to accept that there would be other opportunities.
I had to shift it down a notch and realize that the world wasn’t going to freeze over, and that I could shift it back to high gear later. With “mommy brain”, I knew I wasn’t going to be at the top of my game at that point in my life. But I have incredible role models. Most notable is Jane Lubchenco, currently the Director of the National Oceanic and Atmospheric Administration. During the first part of her career, she shared a position with her husband – each did 50% – and they did that on purpose so they’d be able to enjoy having children and effectively take care of them. Now, she is in the National Academy, is having major scientific impacts, and she did it all despite having kids. If she can do it, why cant the rest of us?
DXS: Given your experiences as a researcher, as a mother, and now as a major science communicator, do you feel that your ability to talk to people has evolved?
LG: Absolutely. I think that the Leopold Training Program, which selects 20 academics from North America to participate in retreats to learn how to be better communicate and lead, has re-inspired all who attended. It has recharged our batteries and allowed us to make realizations that doing good science and putting it out there via scientific publication is just not enough. We also have to push it out there and make it available to a broader, more diverse population. As part of the training, we also learned about different thinking styles – super analytical or super emotional – and after I returned, I had my lab group participate in this type of exercise. And now I feel like I can better assess a persons thinking style and adjust the way I communicate accordingly.
DXS: Did you always have the ability to talk to the general public or does having kids help you to better understand some of the nuances associated with science communication?
LG: I think so. In fact, I am thinking back to when I had a paper in Sciencecome out around the time that I had my first child. It got a lot of news coverage and was featured in Time magazine. I thought it was so cool at the time, but looking back on it I realized that have come a long way. I said something to a journalist, who then asked me to translate it into “plain English.” It was a little bit of a jab.
Now, with kids, I can tell you a lot more about my research and can better see the broader impact. Talking to them helps me to do that. Here is a conversation about my research with my daughter:
L: Mama is working on figuring out how to help the whales that people like to eat. It’s a big problem because some people like to eat whales and some like to see them swimming in the ocean.
G: What we have to do is let the people eat the whales in the ocean, and buy some whales from the pet store to put back in the ocean. How much do whales cost?
L: Good idea. But you can’t buy whales at the store. They are too big. And if we take them all out of the ocean there will be none left.
G: Well instead we should ask the people to eat bad things like sharks.
L: Another good idea. But if we take sharks out there will be no predators to eat the big fish. And the whole ecosystem would collapse.=
G: Well then the people should eat other things like fish instead of whales. They should buy a fishing pole and catch a fish and eat those instead of whales.
L: What about chicken, shouldn’t people just eat chicken?
G: Mama, we can’t kill chickens. Chickens are nicer than fish, so that’s why we have to eat fish.
L: What about just eating vegetables?
G: Oh mama, some people are meat-eaters. And there are no more dinosaurs. They all got extinct. They should have saved some of the dinosaur meat in the freezer for the meat-eaters. When the dinosaurs come back, there will be enough meat to eat and people won’t want to eat whales.
The simplicity of taking myself out of my research bubble and engaging with a creative (and nonlinear?) 7YO has taught me how to be a better communicator – with the media, with my students, and with the general population.
DXS: Do you think these efforts in science communication are helping to shift other peoples perspectives about who a scientist actually is? For instance, are we changing the old crazy haired white guy stereotype?
LG: Well, I hope so. A couple of examples – again, as a mom, one of my daughters a Girl Scout and I get to help with the troop. One of the themes was to teach about environmental and conservations awareness. We did this Crayola molding experiment where we put our fingers into cold water. We then did the same thing except we put modeling clay over our fingers before putting them into the cold water and to learn about adaptations to extreme environments. Also, we play games where they simulate fishing – what if there is plastic? What happens to you if you eat that? My hope is that this shows these young girls that science is both interesting and fun.
Another thing that just happened today is that I was contacted by Martha Stewart’s office, and it seems that some of my research results will be featured in the October issue of Martha Stewart Living. The message here is that I happen to care about the ocean, but I also love sushi. I also I care about health. I am not just a nerd in a lab coat. I am a mom, I do yoga, I have wonderful friends, and here is the kind of science that I do. It seems to me that it is better to connect with others when I can give them something that is relevant to their lives instead of a more abstract ecological theory.
DXS: If you had something you could say to the younger you about getting on your chosen career path, what would you say?
LG: I feel like I have been very effective at figuring out how to get from point A to point B, but less successful at savoring the process. I think that I’d tell myself to make time to celebrate the small victories. I have also learned to identify what kind of research is most exciting, and I would tell myself to say “no” to everything that is only moderately interesting. I tell my grad students that if you don’t dive in head first, you won’t ever know. So why just not give it a try! And if it doesn’t work, move on. Also, if something isn’t making you happy, change! Academia isn’t for everyone, and there is a lot more to life than science.
[Today we have a wonderful guest post from Marie-Claire Shanahan, continuing the conversation about what makes someone a good role model in science. This post first appeared at Shanahan's science education blog, Boundary Vision, and she has graciously agreed to let us share it here, too. Shanahan is an Associate Professor of Science Education and Science Communication at the University of Alberta where she researches social aspects of science such as how and why students decide to pursue science degrees. She teaches courses in science teaching methods, scientific language and sociology of science. Marie-Claire is also a former middle and high school science and math teacher and was thrilled last week when one of her past sixth grade students emailed to ask for advice on becoming a science teacher. She blogs regularly about science education at Boundary Visionand about her love of science and music at The Finch & Pea.] What does it mean to be a good role model? Am I a good role model? Playing around with kids at home or in the middle of a science classroom, adults often ask themselves these questions, especially when it come to girls and science. But despite having asked them many times myself, I don’t think they’re the right questions. Studying how role models influence students shows a process that is much more complicated than it first seems. In some studies, when female students interact with more female professors and peers in science, their own self-concepts in science can be improved . Others studies show that the number of female science teachers at their school seems to have no effect . Finding just the right type of role model is even more challenging. Do role models have to be female? Do they have to be of the same race as the students? There is often an assumption that even images and stories can change students’ minds about who can do science. If so, does it help to show very feminine women with interests in science like thescience cheerleaders? The answer in most of these studies is, almost predictably, yes and no. Diana Betz and Denise Sekaquaptewa’s recent study “My Fair Physicist: Feminine Math and Science role models demotivate young girls” seems to muddy the waters even further, suggesting that overly feminine role models might actually have a negative effect on students.  The study caught my eye when PhD studentSara Callori wrote about it and shared that it made her worry about her own efforts to be a good role model. Betz and Sekaquaptewa worked with two groups of middle school girls. With the first group (144 girls, mostly 11 and 12 years old) they first asked the girls for their three favourite school subjects and categorized any who said science or math as STEM-identified (STEM: Science, Technology, Engineering and Math). All of the girls then read articles about three role models. Some were science/math role models and some were general role models (i.e., described as generally successful students). The researchers mixed things even further so that some of the role models were purposefully feminine (e.g., shown wearing pink and saying they were interested in fashion magazines) and others were supposedly neutral (e.g., shown wearing dark colours and glasses and enjoying reading).* There were feminine and neutral examples for both STEM and non-STEM role models. After the girls read the three articles, the researchers asked them about their future plans to study math and their current perceptions of their abilities and interest in math.** For the most part, the results were as expected. The STEM-identified girls showed more interest in studying math in the future (not really a surprise since they’d already said math and science were their favourite subjects) and the role models didn’t seem to have any effect. Their minds were, for the most part, already made up. What about the non-STEM identified girls, did the role models help them? It’s hard to tell exactly because the researchers didn’t measure the girls’ desire to study math before reading about the role models. It seems though that reading about feminine science role models took away from their desire to study math both in the present and the future. Those who were non-STEM identified and read about feminine STEM role models rated their interest significantly lower than other non-STEM identified girls who read about neutral STEM role models and about non-STEM role models. A little bit surprising was the additional finding that the feminine role models also seemed to lower STEM-identified girls current interest in math (though not their future interest). The authors argue that the issue is unattainability. Other studies have shown that role models can sometimes be intimidating. They can actually turn students off if they seem too successful, such that their career or life paths seem out of reach, or if students can write them off as being much more talented or lucky than themselves. Betz and Sekaquaptewa suggest that the femininity of the role models made them seem doubly successful and therefore even more out of the students’ reach.
The second part of the study was designed to answer this question but is much weaker in design so it’s difficult to say what it adds to the discussion. They used a similar design but with only the STEM role models, feminine and non-feminine (and only 42 students, 20% of whom didn’t receive part of the questionnaire due to an error). The only difference was instead of asking about students interest in studying math they tried to look at the combination of femininity and math success by asking two questions:
“How likely do you think it is that you could be both as successful in math/science AND as feminine or girly as these students by the end of high school?” (p. 5)
“Do being good at math and being girly go together?” (p. 5)
Honestly, it’s at this point that the study loses me. The first question has serious validity issues (and nowhere in the study is the validity of the outcome measures established). First, there are different ways to interpret the question and for students to decide on a rating. A low rating could mean a student doesn’t think they’ll succeed in science even if they really want to. A low rating could also mean that a student has no interest in femininity and rejects the very idea of being successful at both. These are very different things and make the results almost impossible to interpret.
Second these “successes” are likely different in kind. Succeeding in academics is time dependent and it makes sense to ask young students if they aspire to be successful in science. Feminine identity is less future oriented and more likely to be seen as a trait rather a skill that is developed. It probably doesn’t make sense to ask students if they aspire to be more feminine, especially when femininity has been defined as liking fashion magazines and wearing pink.
Question: Dear student, do you aspire to grow up to wear more pink?
Answer (regardless of femininity): Um, that’s a weird question.
With these questions, they found that non-STEM identified girls rated themselves as unlikely to match the dual success of the feminine STEM role models. Because of the problems with the items though, it’s difficult to say what that means. The authors do raise an interesting question about unattainability, though, and I hope they’ll continue to look for ways to explore it further.
So, should graduate students like Sara Callori be worried? Like lots of researchers who care deeply about science, Sara expressed a commendable and strong desire to make a contribution to inspiring young women in physics (a field that continues to have a serious gender imbalance). She writes about her desire to encourage young students and be a good role model:
When I made the decision to go into graduate school for physics, however, my outlook changed. I wanted to be someone who bucked the stereotype: a fashionable, fun, young woman who also is a successful physicist. I thought that if I didn’t look like the stereotypical physicist, I could be someone that was a role model to younger students by demonstrating an alternative to the stereotype of who can be a scientist. …This study also unsettled me on a personal level. I’ve long desired to be a role model to younger students. I enjoy sharing the excitement of physics, especially with those who might be turned away from the subject because of stereotypes or negative perceptions. I always thought that by being outgoing, fun, and yes, feminine would enable me to reach students who see physics as the domain of old white men. These results have me questioning myself, which can only hurt my outreach efforts by making me more self conscious about them. They make me wonder if I have to be disingenuous about who I am in order to avoid being seen as “too feminine” for physics.
To everyone who has felt this way, my strong answer is: NO, please don’t let this dissuade you from outreach efforts. Despite results like this, when studies look at the impact of role models in comparison to other influences, relationships always win over symbols. The role models that make a difference are not the people that kids read about in magazines or that visit their classes for a short period of time. The role models, really mentors, that matter are people in students’ lives: teachers, parents, peers, neighbours, camp leaders, and class volunteers. And for the most part it doesn’t depend on their gender or even their educational success. What matters is how they interact with and support the students. Good role models are there for students, they believe in their abilities and help them explore their own interests.
My advice? Don’t worry about how feminine or masculine you are or if you have the right characteristics to be a role model, just get out there and get to know the kids you want to encourage. Think about what you can do to build their self-confidence in science or to help them find a topic they are passionate about. When it comes to making the most of the interactions you have with science students, there are a few tips for success (and none of them hinge on wearing or not wearing pink):
§ Be supportive and encouraging of students’ interest in science. Take their ideas and aspirations seriously and let them know that you believe in them. This turns out to be by far one of the most powerfulinfluences in people pursuing science. If you do one thing in your interactions with students, make it this.
§Share with students why you love doing science. What are the benefits of being a scientist such as contributing to improving people’s lives or in solving difficult problems? Students often desire careers that meet these characteristics of personal satisfaction but don’t always realize that being a scientist can be like that.
§Don’t hide the fact that there are gender differences in participation in some areas of science (especially physics and engineering). Talk honestly with students about it, being sure to emphasize that differences in ability are NOT the reason for the discrepancies. Talk, for example, about evidence that girls are not given as many opportunities to explore and play with mechanical objects and ask them for their ideas about why some people choose these sciences and others don’t. There are so many ways to encourage and support students in science, don’t waste time worrying about being the perfect role model. If you’re genuinely interested in taking time to connect with students, you are already the right type.
* There are of course immediate questions about how well supported these are as feminine characteristics but I’m willing to allow the researchers that they could probably only choose a few characteristics and had to try to find things that would seem immediately feminine to 11-12 year olds. I still think it’s a shallow treatment of femininity, one that disregards differences in cultural and class definitions of femininity. (And I may or may not still be trying to sort out my feelings about being their gender neutral stereotype, says she wearing grey with large frame glasses and a stack of books beside her).
**The researchers unfortunately did not distinguish between science and math, using them interchangeably despite large differences in gender representation and connections to femininity between biological sciences, physical sciences, math and various branches of engineering.
 Stout, J. G., Dasgupta, N., Hunsinger, M., & McManus, M. A. (2011). STEMing the tide: Using ingroup experts to inoculate women’s self-concept in science, technology, engineering, and mathematics (STEM).Journal of Personality and Social Psychology, 100, 255-270.
 Gilmartin, S., Denson, N., Li, E., Bryant, A., & Aschbacher, P. (2007). Gender ratios in high school science departments: The effect of percent female faculty on multiple dimensions of students’ science identities.Journal of Research in Science Teaching, 44, 980–1009.
 Betz, D., & Sekaquaptewa, D. (2012). My Fair Physicist? Feminine Math and Science Role Models Demotivate Young Girls Social Psychological and Personality Science DOI: 10.1177/1948550612440735
Buck, G. A., Leslie-Pelecky, D., & Kirby, S. K. (2002). Bringing female scientists into the elementary classroom: Confronting the strength of elementary students’ stereotypical images of scientists. Journal of Elementary Science Education, 14(2), 1-9.
Buck, G. A., Plano Clark, V. L., Leslie-Pelecky, D., Lu, Y., & Cerda-Lizarraga, P. (2008). Examining the cognitive processes used by adolescent girls and women scientists in identifying science role models: A feminist approach. Science Education, 92, 2–20.
Cleaves, A. (2005). The formation of science choices in secondary school.International Journal of Science Education, 27, 471–486.
Ratelle, C.F., Larose, S., Guay, F., & Senecal, C. (2005). Perceptions of parental involvement and support as predictors of college students’ persistence in a science curriculum. Journal of Family Psychology, 19, 286–293.
Simpkins, S. D., Davis-Kean, P. E., & Eccles, J. S. (2006). Math and science motivation: A longitudinal examination of the links between choices and beliefs. Developmental Psychology, 42, 70–83.
Stout, J. G., Dasgupta, N., Hunsinger, M., & McManus, M. (2011). STEMing the tide: Using ingroup experts to inoculate women’s self-concept and professional goals in science, technology, engineering, and mathematics (STEM). Journal of Personality and Social Psychology, 100,255–270.
Darlene Cavalier (Twitter) is the hard-working and seemingly tireless founder of Science Cheerleaderand SciStarter. She has held executive positions at Walt Disney Publishing and worked at Discover Magazine for more than 10 years. Darlene incorporated her experience and knowledge in serving as the prinicple investigator of a $1.5 million grant from the National Science Foundation to promote basic research through partnerships with Disney and ABC TV and also has collaborated with the NSF, NBC Sports, and the NFL to produce the Science of NFL Football series. She holds a master’s degree from the University of Pennsylvania where she studied the role of the citizen in science and is herself a former Philadelphia 76ers cheerleader. In addition, she is a writer and senior adviser to Discover Magazine. You can find her full biography here.
On top of all of that, she is also mother to four children. You might be able to blame them for the two-day stomach flu Darlene was just getting over when she talked with Double X Science Managing Editor Emily Willingham about why women pursue professional cheerleading (hint: it’s much more about passion than pay), why cheerleader stereotypes are “bunk,” and why even if Science Cheerleader doesn’t lead all little girls into science, it leaves them with a message about being secure in who they are.
DXS: First, can you give me a quick overview of what your scientific background is and your current connection to science?
A: So I have no formal science degree. My connection to science is that I work and continue to work at Discover magazine. I worked there as business development coordinator, and that’s how I became reintroduced to science. I became a fan of science later in life. After working at Discover for a couple of years and having some children [Cavalier is the mother of four children], I wondered if there was a more significant role for someone like me without a formal science degree. My role at Discover had become curating science on behalf of the magazine. How do we get average public to move in the direction of science literacy?
I went to grad school at the University of Pennsylvania to look at those issues. When I met with an advisor (there), he recommended that I go for a masters in liberal arts, which made sense to me at the time. They created a curriculum for me. Most was in the history and sociology of science and some was in school of education. Piecing all of this together was a turning point for me in my life both prof and personally, I started to learn about these citizen scientists to engage nonscientific members of the public in real scientific research.
I saw huge gaps in getting people to move in that direction. Other countries were enabling citizens to take part in conversations about science policy on national levels. The U.S. didn’t have mechanism for that. That was one gap I saw. Another was people weren’t getting involved in citizen science projects…(they were) hard to find and scattered all over websites. It was a mechanism problem, not philosophical or societal. In grad school, I created a matchmaking site of all citizen science projects I was coming across. I decided to make that database public for people to add their projects, and made it searchable. There were no cheerleaders involved in science cheerleaders when I started the blog…it was about the citizen science projects and reopening this agency for public input. (It was not about) cheerleaders specifically.
DXS: So how did you end up incorporating the cheerleader aspect?
A: That was basically a fun way of using my background–it is surprising to people that I was a (Philadelphia) 76ers cheerleader. I kept it secret for long time at Discover, fearing I wouldn’t be taken seriously. I wish I hadn’t attempted (to keep it) secret; when it was “exposed” at Discover people were great about it. They thought it was pretty neat. So I became more comfortable in that role. I wanted to do a tongue-in-cheek look at this when I was starting the blog that this site really is for everyone. Citizen science projects are for everyone; it doesn’t matter if even a quote–unquote “ditzy blonde cheerleader” can do it, surely the scientists could figure it out, and the politicians.
(When the concept of Science Cheerleader really took off), we thought, “We’re on to something.” Most people loved it. Criticism came from feminist science bloggers, which I totally understand…I learned something there, too… (this idea of), “these women aren’t scientists, what are they doing?” Then I started getting emails from actual NFL NBA cheerleaders, (telling me) “I’m getting PhD in chemistry,” (and saw it as) a great way to merge two parts of my life. I could hardly believe it. I never even had thought to ask cheerleaders if they were studying any of the STEM fields.
It became cyclical. The founder of the U.S. Science and Engineering Festival called and asked Science Cheerleader to come to that festival and perform. I had to tell him I’d never met them. We got a grant from the Burroughs Wellcome fund to cover travel for 11 science cheerleaders to come to Washington and perform. They had awesome outfits, speaking roles. It was more or less an experiment. Amazing performers against a science theme routine and incredible public spokespeople. Applying their talents of being enthusiastic about their team to science and tech careers. They were a huge hit at the festival.
We left each one speak their own language. They’re very diverse. It helped to have that diverse makeup and watching them talk to little kids. Little girls would come up to them, almost like when you see Cinderella, would want their autographs, to touch their uniforms, feel their pompoms. It was a great opportunity to say, “We love cheerleading, but in the daytime I make cars, I’m what you call an engineer.” Some of the dads and the moms were more attracted to the team (the cheerleaders) represented, and they learned that no cheerleader makes a living on 35 bucks a game…they have professions.
We started to realize we were challenging stereotypes of scientists, cheerleaders, engineers. We have so many science cheerleaders in the database, working now with the NFL and NBA, (that) when a local event is happening, I can contact science cheerleaders in the Boston area tell them, and they can go if they want. They don’t have talking points … they say what they want to say. A Patriots cheerleader says cheerleading was great for her professional career, standards were super high for her in college. (You have to maintain) a GPA to be cheerleader and athlete, (and that) was helpful.
DXS: And you’ve encountered some criticism from feminists or women in science. How do you handle that?
A: You can’t be a science cheerleader unless you have science connection. I’m the only fraud in the group. That’s the criterion. What is different, there was so much media play…NPR, CNN, TODAY Show, you can only get across so much in a video. A couple of people took a video where someone says “go science” and assumed we’re just dressing people up as cheerleaders and sending them around to yell that. (But) there’s a lot of depth with what they do.
Many are very accomplished in their fields, going on to do research. One is getting her PhD in chemistry, working on gold nanoparticles to treat pancreatic cancer. That criticism that’s ill informed is the worst type. Putting them in a bad light and they don’t deserve it. They volunteer to do this. They do it because they really believe in it. There are an estimated 3 to 4 million cheerleaders in the US. They want to reach that group, let them know it’s OK to love math and science, (to say) here’s my experience, here’s how I learned what an engineer is, here’s what my day is like. They’re all available to be pen-pal partners. As much as we preach “don’t let other people bother you or criticism bother you,” I don’t like to see ill-informed or misinformed statements.
Q: Have you encountered situations in which your expression of yourself outside the bounds of science has led to people viewing you differently–either more positively or more negatively?
A: Yes. (What) we have is mostly anecdotal…have a number for people coming to site, watching video, we try to save emails and letters that come in from moms of little girls who just want to be cheerleaders but also are talented, and the moms feel they’re talented in math and science and grow concerned about their daughters losing that for their love of cheerleading and dance and are happy to see these role models on the site.
In terms of other positive impacts, if we just look at it from public outreach, it’s been incredible because of the media’s interest. Media interest in this, the teams themselves…it’s not easy to reach Baltimore Ravens fans w positive messages about science and tech or women and science and tech, so when the Ravens repost the interviews and tweet it to their fan base, that’s very positive.
Lines at live events are pretty long with kids lining up to get autographs from the Science Cheerleaders. We always look for local or regional citizen science activity to capitalize on that attention to get those people to do something. For example in South Texas a science and engineering festival. We did our routine, a bunch of people line up for autographs, our choreographer is the reigning Miss United States. That attracts people as I talk about a local researcher who needs their help for citizen science project. (It’s) super simple to use that attention to say “hey, by the way, you’re needed. When you see this crayfish–hold up a picture–it’s considered invasive. Here’s Dr. Zen!” He (Dr. Zen) came out and talked, while they’re waiting inline, a captive audience, and we give the Website where they can get involved.
Our sister site, is now a full-size website called SciStarter, a startup company. That was named one of Philly’s top-10 tech startups last year! It aggregates all of the citizen science projects out there. We rely on that at all of the Science Cheerleader appearances.
I can do what I know how to do, but I would love some grad student or organization that does evaluations or measures outcomes and help me learn more about the metrics, direct outcomes that can be measured, and how do I do that.
DXS: Have you found that your non-science expression of creativity/activity/etc. has in any way informed your understanding of science or how you may talk about it or present it to others?
A: It’s a great question. It’s interesting because that Science Cheerleader blog that I started with and still have–it’s a very diverse audience. There are people who came because they’re reading about their favorite teams’ cheerleaders doing cool things and that ‘s great. I’d have a lot of those types coming to the site, and they’d learn, “hmm that’s interesting I didn’t realize that’s what a chemical engineer does,” then look to their right and see, “hmmm this is happening in Boston”… and take next step from passive reader to getting involved in a citizen science project. The goal is to move them to being actively engaged citizens getting them prepared aware involved in the science policy conversation. I know that sounds so farfetched but not nearly as much as a couple of years ago.
It is not easy to talk to different audiences. I used to preach “know your audience,” but I’ve learned more from my audience than they may have from me. I consider some of the science bloggers, and they’re a part of the audience. I learned they don’t like 76ers involved without science degrees, and we responded to that. What one group likes another won’t. There’s no “one size fits all.” We try to (appeal) to a wide variety of audiences coming to site….from those interested in science policy to people who come because they want more about citizen science efforts. We can point them to these things through SciStarter.
DXS: How comfortable are you expressing your femininity and in what ways? How does this expression influence people’s perception of you in, say, a scientifically oriented context? And does that impression evolve at all?
The initial impression, even through me–and I think the Science Cheerleaders would say this too, even when I was of the Sixers…(pauses)… let’s talk motivation for a minute, why most of these women choose to become professional cheerleaders, why would you do that? The bottom line is that there are very few opportunities to continue dancing and performing once you’re out of college. My personal experience–and you’ll see this in interviews–your options are so limited, and we wanted to continue performing, usually it’s dancing. We see an audition in paper, and they’re looking for people who know how to do triple pirouettes, and the opportunity to continue to perform is there.
I wish we didn’t have to wear those uniforms when I was on the Sixers. I loved every single thing about it except for some of the uniforms. I would love for the NFL and NBA to look and say, “We didn’t realize cheerleaders felt that way and tone it down,” (but) it’s not going to happen. I encourage people to read interviews to see what motivated some of the cheerleaders. I wasn’t a gung-ho Sixers fan who wanted to do this for the team, but some people almost their whole lives dreamed of being a cheerleader for their team.
In terms of embracing being feminine, I don’t know anyone who is that 100% of the time. My hair looked decent, I wore OK clothes, but I don’t walk around like that all the time. I think that the reality of the situation is there’s no one walking around looking like a professional cheerleader all the time. I doubt that the Science Cheerleaders look like that when they go into the lab, not because they want to be taken seriously but for convenience. It s a lot of work to look like that.
I wish that the people who pave the way for these Science Cheerleaders to be exploring the careers they have now–lots are supportive and embrace them but that also happens to be where the toughest critics are embedded. They know better than anyone what it feels like to have somebody work against you. I wish they’d ease up on Science Cheerleaders and let them be all that they can be. They can relate to an audience it’s not easy for us to reach. I can’t reach those little cheerleaders out there myself, but they can, maybe through pom-poms or uniforms or a connection with the moms. It does evolve
Some teams require you to be in school full time or have a full-time job. They want smart cheerleaders because you have to be out doing public speaking so if you’re not articulate or bright…pretty girls and good dancers are a dime a dozen…your success comes down to your interview.
These Science Cheerleaders are by far way more secure in their dual roles than I was. I’m not sure why or how, but when you see them at appearances, they’re looking for ways to embrace these two roles. They’ll say in their interview, I don’t care what people in my lab think about my wearing makeup and so on, and they mean it. These women walk the walk.
DXS: If you had something you could say to the younger you, back when you weren’t so comfortable with yourself about the role of expression and creativity in your chosen career path, what would you say?
A: If I had read one of these interviews when I was, say, in fifth grade, and I read one of those Science Cheerleader interviews, it would resonate w me in a different way. It might not have an impact on me personally when I was a kid…the cheerleaders on our team, we were athletes. Most cheerleaders are leaders in their schools, involved in leadership and academics, student government. The stereotype is total bunk.
I can tell you that in some point in my life, I can think back to times, like my first big job at Discover, had I read these interviews as a kid, I may have felt more comfortable about being authentic about every aspect of me.
To use the Pop Warner example, we set a world record with them, 1300 little cheerleaders cheering for science for five minutes. I have a sneaking suspicion that fast forward 10 years from now, they might be interviewed, by you maybe, about how they got interested in science, and they might say, when I as in 8th grade, I got called in to do this science cheer thing, and it opened my eyes to science as a valid career. If it doesn’t happen at a young age for some of these girls, they might reflect back to something they experienced science cheerleading and feel entitled to embrace all that they are and feel good about that.
See the Science Cheerleaders in action at the Science and Engineering Festival: