Biology Explainer: The big 4 building blocks of life–carbohydrates, fats, proteins, and nucleic acids

The short version
  • 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.
Carbohydrates

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.

Proteins

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.

Nucleic Acids

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.


 By Emily Willingham, DXS managing editor 
This material originally appeared in similar form in Emily Willingham’s Complete Idiot’s Guide to College Biology

Motherhood Defined: It is in the heart of the beholder

“Motherhood”: Sculpture at the Catacumba Park, Rio de Janeiro, Brazil
Motherhood.  It can mean many things, and our own definition of it is largely defined by our individual experiences.  To one person, motherhood might simply mean the act of raising children; to another, motherhood might be what defines them.  

It is not uncommon to generalize the concept of “motherhood” and lump everyone who upholds a single criterion – being a mom – into one group.   But, really, motherhood affects us all in one way or another, and that way is as unique as the pattern of curves and ridges on a fingertip.

Despite the recent outbreak of (heated) discussion surrounding the Time cover story depicting a beautiful and young woman nursing a toddler, and the questioning if following a certain philosophy makes one more or less of a mother, humans, as a whole, are truly bound by a common goal: to raise the next generation to the best of our abilities under the circumstances at hand.   
But, there is no one answer.
Every mom will have her own definition of motherhood.  But, being a mom is by no means a prerequisite for understanding motherhood as it relates to an individual.  For this special Mother’s Day post, we would like to pay homage to motherhood in its many forms.  Here you will not find a singular description of motherhood.  What you will find, however, is what it means on a more personal level, which is to say that the definition can only come from the heart. 

Thank you to all of the wonderful people who participated in this project (and with short notice!) – we have answers in paragraph, tweet, and prose forms.    

Ilina Ewen, Blogger at Dirt and Noise@IlinaP

What does motherhood mean to me?

Motherhood means feeling a kaleidoscope of emotions simultaneously – fear, glee, worry, angst, pride. And it means being an advocate and a revolutionary who empowers her children to engage in society in a meaningful, fun, vibrant way. And lastly, motherhood means always giving up the biggest piece of cake and the last popsicle and being okay with that.

Momma, PhD, Scientist/Wife/Mother

Motherhood means accepting responsibility. If you read the news or listen to the hype, you know what I mean.  Every choice you make, from before a child is conceived, until long after you’re dead, there is someone out there that will tell you how it impacted your kid. As my nana always said, “It’s always the mother’s fault.”  I just hope that as the time passes I get more credit than blame for how my kids turn out.

Motherhood is how you stretch your heart in ways you never thought possible. It’s how you love through the ups & down, the challenges that life brings. And, it lasts a lifetime from that first tiny cry. 

Chris Gunter, Director of Research Affairs, HudsonAlpha Institute for Biotechnology, @Girlscientist

I’m a human geneticist by training, so I’ve been told having a child is the ultimate version of participating in my research. But the science analogy that best summarizes it for me is maternal-fetal microchimerism. Data demonstrating that my son and I each likely have some of each other’s intact cells inside us forever — as I have with my mother, and she with hers, and so on — beautifully represent to me the meaning of motherhood. As the quote from Elizabeth Stone goes, having a child “is to decide forever to have your heart go walking around outside your body.” To me, that includes half my DNA, some of my cells, and so many of my hopes and dreams, all in one sweet, kissable package.

Dr. Cheryl G. Murphy, Optometrist and Science Writer, @MurphyOD

Motherhood: As a mom of triplets, some would say I have triple the work but I like to think of it as triple the hugs, triple the joy, triple the fun! And when people ask me what it’s like to become a mom I tell them “it’s the toughest job you’ll ever love.” Happy Mother’s Day to all of you amazing, do-it-all moms out there! 

Matt Shipman, Science writer, and founder of the First Step Project@Shiplives

I’m a man, so I obviously have no first-hand experience as a mother. That said, I was raised by a (wonderful) single mother, and have had the pleasure of watching my wife be an awesome mom to our three daughters. Those experiences have shaped my impressions of motherhood. To me, motherhood means being kind, but honest. Being gentle, but strong. Being nurturing, but encouraging independence. Motherhood is letting your kids think you are ten feet tall and bulletproof, so they feel you can keep them safe — even though there’s stuff out there that scares the hell out of you. It’s encouraging your kids to learn new things and to work their butts off in school, without making them feel stupid. Motherhood is leading by example when it comes to telling right from wrong, and showing your kids which battles are worth fighting. And, when the time comes, motherhood is letting go of the reins to see where the kids go on their own. Motherhood is not for wimps.

Julie Marsh, VP of Operations, Cool Mom Picks + Cool Mom Tech@coolmompicks@coolmomtech 

To me, motherhood means leading by example in the most pivotal role I’ve ever accepted.

Emily Willingham, PhD, managing editor, Double X Science, science writer and editor, biologist, autism parent, mother, @ejwillingham

The greatest realization of motherhood for me was that the children we have are people of their own, not “our” children or some kind of nutty, messy, screaming, demanding “other” invading our space, disrupting our lives, and taking our precious time. They are people I love to have around me because they make me laugh, they bring out the teacher in me (not hard to do), they are cool and interesting and imaginative and fun, and each of them (I have three) is a complete individual with a unique personality, outlook, potential, talent, and beautiful, beautiful face that I love to see every day. Just as I choose to spend time with others whom I love, respect, admire, and laugh with, I choose to do the same with my children. That said, I also still have what I had before my children arrived–a happy, full busy life with a partner to whom I seem to grow closer every day, and work that I love. Thanks to my children, I’ve got something even more–three more wonderful people added to my life whom I am deeply delighted and, frankly, honored to know. As Bill Murray’s character in Lost in Translation observes, “They learn how to walk and they learn how to talk… and you want to be with them. And they turn out to be the most delightful people you will ever meet in your life.”

Alice Callahan, Science of Mom@Scienceofmom

What does motherhood mean to me?

Motherhood is humbling. Of all the endeavors I have tackled in my life, never have I wanted so badly to get everything right and yet known that I would not. Never have I been so emotionally invested in the results, so exhausted by the labor of it, and also, so strangely confident that it will turn out OK. It is the most human thing I have ever done.

David Wescott, It’s not a Lecture@dwescott1

For men whose ideas of fatherhood were shaped in large part by its absence in our own lives, motherhood may mean something a bit different.  I’m by no means a scholar, but I’ve had the opportunity to speak often and at length with women across the globe on this topic, and to curate their thoughts a bit. These women talk about the feeling of connection to their children they know no one else has.  They describe the magic of watching their little ones narrate the moments of discovery in their lives. They talk about how their children “complete the circle” and teach them the other side of unconditional love. They help you understand why people invoke the lioness or the grizzly when describing the protective instinct.  

My perspective of motherhood is a lot like that last sentiment – it’s the unyielding power that rises up in you when you realize a little person depends on you for everything.  I know that many men step up when left in that situation – I’ve seen it first-hand – but I suspect the feeling is different for women because this little person actually came from you, is an extension of you, is connected to you in ways no man will ever fully understand. 

When I think of motherhood, I think of unconditional love. It’s what my mother gave to me, and it’s what I expect I would feel for the children I don’t intend to have. My mother made countless sacrifices for me, but she was independent and did not allow motherhood to define her. She has always encouraged me to be my own person and chase my own dreams. She didn’t want me to feel constrained by gender roles. I feel fortunate to live in a time when motherhood is a choice, not an obligation. I admire my peers who have chosen to have kids, but I’m content to enjoy the rich mother-daughter relationship I have with my mom without feeling obliged to replicate it. 

Editors note: Christie has recently written a wonderful piece on motherhood at Last Word On Nothing.  Go read it!

Carin Bondar, Blogger and Filmmaker for Scientific American, the David Suzuki Foundation and Huffington Post, @drbondar

As a working mother of 4 very young children, I don’t have much time to reflect on much – this stage of my life is pretty much dedicated to surviving.  I do know that once I decided that I really wanted to start having children (when I was almost finished my PhD) – my life seemed oddly empty.  It was as though I realized that something tremendous was missing and I became completely obsessed with wanting them.  Now that I have them (yes all 4 of them!) there are many times when I feel completely overwhelmed and exhausted, but  I will always remember the feelings of desire to have a family.  I know that my life would be empty and incomplete without my lovely babies.

Jeanne Garbarino, Biology Editor at Double X Science and Rockefeller University Postdoc, @JeanneGarb

For five years, I have been a mother.  I have learned – and am still learning – some very difficult lessons on time management and prioritization, on choosing my battles wisely, and on being ok when things aren’t exactly perfect (or even decent).  But, to be honest, these are all lessons I really needed to have in my life.  Though it might seem a bit counterintuitive, the mostly delightful chaos associated with rearing my girls has given me more focus.  For me, motherhood is more of a state of being, and it has helped me learn how to not sweat the small stuff (for the most part), to be more mindful of the present, and to think more about the future.  Oh, and motherhood also gives me that special golden ticket to buy really cool games and toys (because who isn’t interested in seeing what Doggie Doo is all about), as well as provides a dependable companion for roller coaster rides.

Motherhood had made me stand in my living room as my kids run around me and think how odd it is that I protect these three little persons. Motherhood has made me weep at the sight of children hurt or hungry; has made me rageful at a world where monsters are free; has made me face my own capacity for anger; and it has graced me with random gifts like hysterical laughter over blueberry waffles at the breakfast table. 

Rebecca Guenard, PhD, Atomic-o-licious@BGuenard

Motherhood

Listening to stories,

admiring all they know.

Hugging, kissing,

holding Cheeto-covered hands.

Tightening hockey skates,

washing baseball uniforms.

He stands on the mound alone.

From Twitter

@Scientistmother: motherhood means joyous bittersweet scary make a better person love no matter what

@Cbardmayes: mh=if my heart was as the universe, still would not be big enough to hold all the love for my son & his smiles #happymunkimama

@Labroides:motherhood is seeing my wife find reserves of strength patience and love that we didn’t know she had

@Babyattachmode:to me motherhood means realizing that I have this enormous amount of love for such a little person!

@Jtothehizzoe:The “motherhood” is that end of town where all the moms hang out, actin’ all hard, right?

Breast cancer screening and treatment, especially in younger women

[Editor's note: I was on Twitter, as usual, a couple of days ago, and started seeing tweets with the hashtag #SSCAbc. They contained information that I, an avid consumer of science and medical information, don't normally see addressed in breast cancer stories, including for young women with breast cancer and how to talk to children about having breast cancer. I've aggregated some of those tweets below, but you can read more at the hashtag here, which represents the Seattle Cancer Care Alliance, whose representatives were conducting the Twitter session.]

[View the story "Seattle Cancer Care Alliance: Talking about breast cancer" on Storify]

Seattle Cancer Care Alliance: Talking about breast cancer

http://www.sccablog.org/2012/10/tweeting-for-breast-cancer-awareness-month/ Twitter handles @SeattleCCA, @UWMedicineNews, and @HutchinsonCtr; also @jrgralow and @SeattleMamaDoc

Storified by Emily Willingham · Mon, Oct 15 2012 13:00:07

“@stales: MT @SeattleMamaDoc: Exercise lowers hormone levels, consequently lowers risk of breast cancer.#SCCAbc #SCCAbc”MESFER AL SHAHRANI
#SCCAbc Topic 3: If your mother or sister had breast cancer, especially < age 40, you may be at increased risk.Julie Gralow
RT @jrgralow: Breast cancer in multiple family members, especially at young age, increases risk. Great info: http://ow.ly/euFq8 #SCCAbcWendySueSwanson MD
THIS IS A TRIPLE WHAMMY: Breast feeding is good for mom, great for baby, & lowers breast cancer risk (less estrogen while nursing) #SCCAbcWendySueSwanson MD
RT @SeattleCCA: Recap T2: earlier age at first #pregnancy, more pregnancies & #breastfeeding can decrease #breastcancer risk #SCCAbcAlicia C. Staley
Tough for many of us—and not necessary–but earlier pregnancies (esp under age 20) dec risk of breast cancer #SCCAbcWendySueSwanson MD
RT @SeattleMamaDoc: Tell your teens. Scream it from the rooftop RT @jrgralow: #SCCAbc Oral contraceptives do NOT increase breast cancer riskDominique B.
TOPIC 4 Q1: What is the recommended age for a #mammogram, and why? #SCCAbcSeattle Cancer Care
RT @jrgralow: We recommend starting age 40 for most women. If you have higher or lower risk than average this will vary. #SCCAbcUW Medicine News
Mammograms can decrease rate of death from breast cancer, especially true in those women over age 50 #SCCAbc http://1.usa.gov/puQ0NcWendySueSwanson MD
RT @seattlecca: T4 Q2: What else can a woman do other than a #mammogram to screen for #breastcancer? #SCCAbcUW Medicine News
RT @jrgralow: #SCCAbc Topic 4: Younger women have denser breasts, making mammos less reliable. Here’s some info: http://ow.ly/euH6tUW Medicine News
RT @jrgralow:Topic 4: Ultrasound is great in young, dense breast when abnormality is noted. So far, not a good screening tool yet. #SCCAbcUW Medicine News
#SCCAbc Topic 4: Breast MRI more sensitive than mammo in young women. For women with strong family history we recommend breast MRI .Julie Gralow
BRCA1 & BRCA2 are genes that can be passed in families & inc your risk of breast cancer. There’s blood tests 4 BRCA1&2 gene changes. #SCCAbcWendySueSwanson MD
#SCCAbc Topic 3: We can test for BRCA1/2, also sometimes PTEN or p53 or other tests may be applicable.Julie Gralow
RT @SeattleMamaDoc If concerned abt costs of genetic test, call ur insurance prior to tests. I also rec genetic counseling visits. #SCCAbcAlicia C. Staley
RT @SeattleMamaDoc Mammos, like most things, arent perfect. Esp in the young. If high risk 2 fam history/genes, ask abt breast MRI #SCCAbcAlicia C. Staley
RT @uwmedicinenews: Topic 5 Q1: how would you recommend speaking with young children about a loved one’s breast cancer? #SCCAbcHutchinson Center
More than anything, take ur time in explaining breast ca diagnosis with children. There isn’t urgent rush for all details at once #SCCAbcWendySueSwanson MD
@jrgralow Children learn fear of cancer from us. Be open/provide info, take them to chemo if they want, helps normalize #gr8 advice #SCCAbcUW Medicine News
RT @jrgralow: SCCAbc Topic 5: I love this book (by one of my patients) on talking about chemo with kids. http://ow.ly/euInm #SCCAbcSeattle Cancer Care
RT @jrgralow: Young Survival Coalition offers great support for young women w breast cancer http://www.youngsurvival.org/ #SCCAbcWendySueSwanson MD
RT @SeattleMamaDoc: Tip: Let people help you on YOUR terms when navigating cancer diagnosis &raising children. #SCCAbcUW Medicine News
#SCCAbc Topic 5: 2 great sets of info on coping and relationships and cancer. http://ow.ly/euITz http://ow.ly/euIUHJulie Gralow
Consider freezing eggs before chemo RT @jrgralow #SCCAbc T2: Chemo can put young women into early menopause, decrease future ferility.Ruth Ann Crystal, MD
RT @jrgralow: #SCCAbc Topic 1: Presidents Cancer Panel report on healthly lifestyles and cancer: http://ow.ly/er0pE #SCCAbcAlicia C. Staley
T4Q1: Thanks to @Safeway for supporting SCCA’s #MammoVan, will be in Safeway parking lots throughout Oct: http://ow.ly/euGjx #SCCAbcSeattle Cancer Care
RT @SeattleMamaDoc: PS– Breast feeding after breast cancer is okay: http://ti.me/coREKR #SCCAbc cc @brochmanSara

Double Xplainer: Once in a Blue Moon

Full Moon, from Flickr user Proggie under
Creative Commons license.
Tonight—August 31, 2012— is the second full Moon of August. The last time two full Moons occurred in the same month was in 2010, and the next will be in 2015, so while the events are rare, they aren’t terribly uncommon either. In fact, you’ve probably heard the second full Moon given a name: “blue moon”. (The Moon will not appear to be a blue color, though, cool as that would be. More on that in a bit.) What you may not know is that this term dates back only to 1946, and is actually a mistake.

According to Sky and Telescope, a premiere astronomy magazine (check your local library!), the writer James Hugh Pruett made an incorrect assumption about the use of the term “blue moon” in his March 1946 article. His source was the Maine Farmers’ Almanac, but he misinterpreted it. The almanac used “blue moon” to refer to the rare occasion when four full Moons happen in one season, when there are usually only three. By the almanac’s standards, tonight’s full moon is not a blue moon (though there will be one on August 21, 2013).

However, even that definition of “blue moon” apparently only dates to the early 19th century. In its colloquial, non-astronomical sense, a “blue moon” is something that rarely or never happens: like the Moon appearing blue. The Moon is white and gray when it’s high in the sky, and can appear very red, orange, or yellow near the horizon for the same reason the Sun does. As far as I can tell, the only time the Moon appears blue is when there’s a lot of volcanic ash in the air, also a rare event (thankfully) for most of the world. The popular song “Blue Moon” (written by everyone’s favorite gay misanthrope, Lorenz Hart) uses “blue” to mean sad, rather than rare.

I’m perfectly happy to keep the common mistaken usage of “blue moon” around, though, since it’s not really a big deal to me. Call tonight’s full Moon a blue moon, and I’ll back you up. However, because it’s me, let’s talk about the Moon and the Sun and why this stuff is kind of arbitrary.

The Moon and the Sun Don’t Get Along

The calendar used in much of the world is the Gregorian calendar, named for Pope Gregory XIII, who instituted it in 1582. The Gregorian calendar, in turn, was based on the older Roman calendar (known as the Julian calendar, for famous pinup girl Julie Callender Julius Caesar). The Romans’ calendar was based on the Sun: a year is the length of time for the Sun to return to the same spot in the sky. This length of time is approximate 365.25 days, which is why there’s a leap year every four years. (Experts know I’m simplifying; if you want more information, see this post at Galileo’s Pendulum.)

A problem arises when you try to break the year into smaller pieces. Traditionally, this has been done through reference to the Moon’s phases. The time to cycle through all the phases of the Moon is called a lunation, which is about 29 days, 12 hours, 44 minutes, and 3 seconds long. You don’t need to pull out a calculator to realize that a lunation doesn’t divide into a year evenly, but it’s still a reasonable way to mark the passage of time within a year, so it’s the foundation of the month (or moonth).

Many calendars—the traditional Chinese calendar, the Jewish calendar, and others—define the month based on a lunation, but don’t fix the number of months in a year. That means some years have 12 months, and others have 13: a leap month. It also means that holidays in these calendars move relative to the Gregorian calendar, such that Yom Kippur or the Chinese New Year don’t fall on the same date in 2012 that they did in 2011. (The Christian religious calendar combines aspects of the Jewish and the Gregorian calendars: Christmas is always December 25, but Easter and associated holidays are tied to Passover—which is coupled to the first full Moon after the spring equinox, and so can occur in a variety of dates in March and April.)

Another resolution to the problem of lunations vs. Sun is to ignore the Sun; this is what the Islamic calendar does. Months are defined by lunations, and the year is precisely 12 months, meaning the year in this calendar is 354 or 355 days long. This is why the holy month of Ramadan moves throughout the Gregorian year, happening sometimes in summer, and sometimes in winter.

The Gregorian calendar does things oppositely to the Islamic calendar: while months are defined, they are not based on a lunation at all. Months may be 30 days long (roughly one lunation), 31 days, or 28 days; the latter two options make no astronomical sense at all. Solar-only calendars have some advantages: since seasons are defined relative to the Sun, the equinoxes and solstices happen roughly on the same date every year, which doesn’t happen in lunation-based calendars. It’s all a matter of taste, culture, and convenience, however, since the cycles of Sun and the Moon don’t cooperate with the length of the day on Earth, or with each other.

Blue moons in the common post-1946 usage never happen in lunation-based calendar systems because by definition each phase of the Moon only occurs once in a month. On the other hand, the version from the Maine Farmers’ Almanac is relevant to any calendar system, because it’s defined by the seasons. As I wrote in my earlier DXS post, seasons are defined by the orbit of Earth around the Sun, and the relative orientation of Earth’s axis. Thus, summer is the same number of days whatever calendar system you use, even though it may not always be the same number of months. In a typical season, there will be three full Moons, but because of the mismatch between lunations and the time between equinoxes and solstices, some rare seasons may have four full Moons.

The Moon and Sun have provided patterns for human life and culture, metaphors for poetry and drama, and of course lots of superstition and pseudoscience. However, one thing most people can agree upon: the full Moon, blue or not, is a thing of beauty. If you can, go out tonight and have a look at it—and give it a wink in honor of the first human to set foot on it, Neil Armstrong.

Shmeat and Potatoes: The dinner of the future?

By Jeanne Garbarino, Biology Editor


(Source)

“Meatloaf, beatloaf, double s[h]meatloaf…”  Was little Randy on to something?
Food engineering has been on an incredibly strange journey, but there is none stranger (at least to me) than the concept of in vitro meat.  Colloquially referred to as “shmeat,” a term born out of mashing up the phrase “sheets of meat,” in vitro meat may be available in our grocer’s refrigerator section in just a few years.  But how exactly is shmeat produced and how does it compare to, you know, that which is derived from actual animals?  Here, I hope to shed some light on this petri dish to kitchen dish phenomenon.

The shmeaty deets

When it comes to producing shmeat, scientists are taking advantage the extensive cell culture technologies that have been developed over the course of the 20th century (for a brief history of these developments, check this out).  Because of what we have learned, we can easily determine the conditions under which cells grow best, and swiftly turn a few cells into a few million cells.  However, things can get a little tricky when growing complex, three-dimensional tissues like steak or boneless chicken breast.

(Source)

For instance, lets consider a living, breathing cow.  Most people seem to enjoy fancy cuts like beef tenderloin, which, before the butcher gets to it, is located near the back of the cow.  In order for that meat to be nice and juicy, it needs to have enough nutrients and oxygen to grow.  In addition, muscles (in this case, the tenderloin) need stimulation, and in the cow (and us too!) that is achieved by flexing and relaxing.

If shmeat is to be successfully engineered, scientists need to replicate all of the complexities that occur during the normal life of an actual animal.  While the technology for making shmeat is still being optimized, the components involved in this meat-making scheme successfully address many of the major issues with growing whole tissues in a laboratory. 

The first step in culturing meat is to get some muscle cells from an animal.  Because cells divide as they grow, a single animal could, in theory, provide enough cells to make meat for many, many people – and for a long period of time.  However, the major hurdle is creating a three-dimensional tissue, you know, something that would actually resemble a steak. 

Normally, cells will grow in a single layer on a petri dish, with a thickness that can only be measured by using a microscope.  Obviously that serving size would not be very satisfying.  In order to create that delicious three-dimensional look, feel, and taste, and be substantial enough to count as a meal, scientists have developed a way to grow the muscle cells on scaffold made of natural and edible material.  As sheets of cells grow on these scaffolds, they are laid on top of each other to bulk up the shmeat (hence “sheets of meat”).  But, in order for the cells on the inside of this 3D mass to grow as well as the cells on the outside, there has to be an sufficient way to deliver nutrients and oxygen to all cells. 

Back to the tenderloin – when it is still in the cow, the cells that make up this piece of meat are in close contact to a series of veins, arteries, and capillaries.  Termed vasculature, this system allows for the cells to obtain nutrients and oxygen, while simultaneously allowing cells to dump any waste into the blood stream.  There are some suggestionsthat the shmeat can be vascularized (grown such that a network of blood vessels are formed); however, the nutrient delivery system most widely used at this point is something called a bioreactor

A Bioreactor (Source)

This contraption is designed to support biologically active materials and how it works is actually quite cool.  The cells are placed in the cylindrical bioreactor, which spins at a rate that balances multiple physical forces, which keep the entire cell mass fully submerged in liquid growth medium at all times.  This growth medium is constantly refreshed, ensuring that the cells are always supplied with a maximum level of growth factors.  In essence, the shmeat is kept in a perpetual free fall state while it grows.         

But there is one last piece to the meat-growing puzzle, and that is regular exercise.  If we look at meat on a purely biological level, we would see that it is just a series of cells arranged to form muscle tissue.  Without regular stimulation, muscles will waste away (atrophy).  Clearly, wasting shmeat would not be very efficient (or tasty).  So, shmeat engineers have reduced the basic biological process involved with muscle stimulationto the most basic components – mechanical contraction and electrical stimulation.  Though mechanical contraction (the controlled stretching and relaxing of the growing muscle fibers) has been shown to be effective, it is not exactly feasible on a large scale.  Electrical stimulation – the process of administering regular electrical pulses to the cells – is actually more effective than mechanical contraction and can be widely performed.  Therefore, it seems to be a more viable option for shmeat production.    

Why in the world would we grow meat in a petri dish?

Grill it, braise it, broil it, roast it – as long as it tastes good, most people don’t usually question the origins of their meat.  Doing so could easily make one think twice about what they are eating.  Traditionally speaking, every slab of meat begins with a live animal – cow, pig, lamb, poultry (yes, despite what my grandmother says, this vegetarian does consider chicken to be meat) – with each animal only being able to provide a finite number of servings.  While shmeat does ultimately begin with a live animal, only a few muscle, fat, and other cells are required.

Given the theoretical amount that can be produced with just a few cells, the efficiency of traditional meat-generating farms and slaughterhouses is becoming increasingly scrutinized.  There are obvious costs – economic, agricultural, environmental – that are associated with livestock, and it has been proposed(article behind dumb pay wall, grrrr….) that shmeat engineering would substantially cut these costs.  For instance, it has been projected that shmeat production could use up to 45% less energy, compared to traditional farming methods.  Furthermore, relative to the current meat production process, culturing shmeat would use 99% less land, 82-96% less water, and would significantly reduce the amount of greenhouse gasesproduced. 

The impact of shmeat compared to tradtional agricultural processes.
(Environ. Sci. Technol., 2011, 45 (14), pp 6117–6123)

But the potential benefits of making the shift toward shmeat (as opposed to meat) doesn’t stop with its positive environmental impact.  From a nutritional standpoint, it is possible to produce shmeat in a way that would significantly reduce the amount of saturated fat it contains.  Additionally, there are technologies that would allow shmeat to be enriched with heart-healthy omega-3 fats, as well as other types of polyunsaturated fats.  In essence, shmeat could possibly help combat our growing obesity epidemic, as well as the associated illnesses such as diabetes and heart disease.  That’s *if* it can be produced in a way that is both affordable and widely available (more on that in a bit). 

In terms of health, switching to shmeat would improve more than our waistlines.  Because shmeat would be produced in a sterile environment, the incidence of E. coli and other bacterial and/or viral contamination would be next to nothing relative to current meat production methods.  On a more superficial level, shmeat technology would allow for the introduction of some very exotic meats into the mainstream.  Because this technology does not require an animal to be slaughtered (another good reason that supports shmeat productions) and it is not limited to the more common sources of meat, it would be entirely possible to make things like panda sausage and crocodile burgers.  But, of course, getting people to actually eat meat grown in a test-tube is another issue…

The limitations of shmeat

Now that I’ve just spent a few paragraphs singing shmeat’s praises, it is probably best that I fill you in on some of the major roadblocks associated with shmeat production.  According to scientists, there are two main concerns: the first is that shmeat production will not be subjected to the normal regulatory (homeostatic) mechanisms that naturally occur in animals (scientists are having trouble figuring out how to replicate these processes); and the second is that shmeat engineering technology has not evolved enough so that it can occur on an industrial scale.  Because of these issues and others, the cost of culturing shmeat in the laboratory is very high.  But, there has always got to be a starting point.  As the technologies advance, the cost-production ratios will decrease and, eventually, shmeat will find its way to the dining table – our dining table. 

Interestingly, the folks at PETA are all for shmeat and offered a one million dollar prize to the first group who could come up with the technology to make shmeat commercially available by June, 2012.  Obviously, that did not happen, and the contest has been extended to January 2013 (this offer has been on the table since 2008).  But, the first tastes test for shmeat hamburgers is going down in October of this year. 

At the moment, the largest piece of shmeat to be created is about the size of a contact lens and my guess is that, barring unforeseen technological breakthroughs, this reward will go unclaimed for a long, long time.  But, many a miracle has been known to happen in about nine months time…   

A few final thoughts on shmeat

With the world population expected to hit 9 billion by 2050, which will be accompanied by a major increase in the need for the amount of food produced, perhaps shmeat technology will become one of the critical innovations required for our collective survival on this planet.  But, there is just one thing: the ick factor.  It is a little hard for me to weigh in on this issue because almost all meat seems gross to me (unless it is a pulled pork sandwich, lovingly made by my long-time pal and professional chef – Julie Hall).  While most of my peers have less of an aversion to meat, I can’t imagine that they would eagerly line up for a whopping serving of lab-grown shmeat. 

But, say scientists finally figure it out and shmeat production is scaled up for mass consumption – how will the agricultural sector react?  As of right now, the agricultural industry in the USA is worth over $70 billion, with a yearly beef consumptiontipping over the 26 million pound mark (of which 8.7% is exported).  Shmeat probably has definitely gotten the attention of cattle farmers (and other meat farmers/production companies) and, given the size of this industry, I wonder how much muscle will be used to block shmeat from becoming a household phenomenon.

Over all, I think that shmeat is a revolutionary idea as it could have a significant impact on humanity.  However, there are many complex questions that need to be both asked andanswered.  As excited as I am at the thought of not having to kill an animal to eat a steak, I still remain skeptical (though this sentiment may not have been fully present for the majority of this post).  Will shmeat be produced in such a way that it will be indistinguishable from traditional meat?  Additionally, will shmeat live up to all of these expectations?  I am going to try and keep a positive outlook with this one.  Perhaps the next time I actually step foot in a kitchen to prepare a meal, I’ll follow Randy’s lead by making a shmeatloaf, served alongside a heaping side of mashed potatoes.  Now that’s some pretty cool kitchen science.

And now, an oldie but a goodie (let it be known that I am in love with Stephen Colbert):

The Colbert Report Mon – Thurs 11:30pm / 10:30c
World of Nahlej – Shmeat
www.colbertnation.com
Colbert Report Full Episodes Political Humor & Satire Blog Video Archive

For more information:
The Brian Lehrer Show, Shmeat: It’s whats for dinner

Real science vs. fake science: How can you tell them apart?


Phrenology is a famous pseudoscience that involved determining
a person’s personality based on bumps on the skull.

Pseudoscience is the shaky foundation of practices–often medically related–that lack a basis in evidence. It’s “fake” science dressed up, sometimes quite carefully, to look like the real thing. If you’re alive, you’ve encountered it, whether it was the guy at the mall trying to sell you Power Balance bracelets, the shampoo commercial promising you that “amino acids” will make your hair shiny, or the peddlers of “natural remedies” or fad diet plans, who in a classic expansion of a basic tenet of advertising, make you think you have a problem so they can sell you something to solve it. 

Pseudosciences are usually pretty easily identified by their emphasis on confirmation over refutation, on physically impossible claims, and on terms charged with emotion or false “sciencey-ness,” which is kind of like “truthiness” minus Stephen Colbert. Sometimes, what peddlers of pseudoscience say may have a kernel of real truth that makes it seem plausible. But even that kernel is typically at most a half truth, and often, it’s that other half they’re leaving out that makes what they’re selling pointless and ineffectual.

If we could hand out cheat sheets for people of sound mind to use when considering a product, book, therapy, or remedy, the following would constitute the top-10 questions you should always ask yourself–and answer–before shelling out the benjamins for anything, whether it’s anti-aging cream, a diet fad program, books purporting to tell you secrets your doctor won’t, or jewelry items containing magnets:

1. What is the source Continue reading