Study Guide

Biomolecules and the Chemistry of Life

Biomolecules and the Chemistry of Life Introduction

Simply put, chemistry is the foundation for biology. Hang on a second; don't get all bent out of shape just yet. We know you did not exactly sign up for Chem 101, but we do not expect you to go out and win a Nobel Prize in Chemistry. However, if you understand a few basic ideas and concepts, this knowledge will nurture your budding love of bio. On that note, welcome to the atomic level of biology!

Let's go through the basics with a quick once-over. If it all starts to feel like a bit much, keep in mind that this is only the introduction; we will get into a more thorough discussion of all these topics later.

Atoms are the basic structural units of matter, and the subatomic particles that constitute atoms—namely, protons, neutrons, and electrons—interact with each other in several ways.

Things to note:

Protons have a charge of +1,
 
Neutrons have a charge of 0, and
 
Electrons have a charge of -1.

Gained or lost electrons result in the formation of charged particles; changing the number of neutrons results in different versions of atoms, called isotopes. All radioactive compounds are isotopes.

And of course, we cannot forget about the beloved bonds! Unfortunately for us, these bonds don't come with any voluptuous vixen co-stars.

Ionic bonds are the bonds formed between oppositely charged ions, whereas covalent bonds form when electrons are shared between electrically neutral atoms.

Not everyone is equally good at sharing, even at the atomic level, and the consequence of this universal truth is that many molecules have uneven distributions of electrons. We call these polar molecules, and they have profound implications for much of the biology you will learn about in a short while.

Hydrogen bonds form between oppositely charged portions of polar molecules. Water (good ol' H-2-to-the-O) is highly polar and forms hydrogen bonds, and these traits are part of what makes water unique and important to life. Oh…did we mention how really, super important water is to life? No? Our bad.

These atomic building blocks and the interactions among them are responsible for all the biological molecules that constitute life forms. Biological molecules come in many varieties, but can be grouped into:

  • Carbohydrates
     
  • Lipids
     
  • Proteins
     
  • Nucleic acids

The carbohydrate's claim to fame is its ability to act as a good source of energy, but carbohydrates are also decent for energy storage and transport, and in some cases, for structural support. You know the deal: Carbs give you the physical and mental energy that helps you out when you need to work out, play that afterschool game, or take your SATs and APs.

Lipids are the masters of energy storage, and some have important structural roles or serve as hormones, among other things. You may be most familiar with lipids as fat, but every one of the cells in your body has a membrane, or layer, of lipids that protects it from its environment. So don't diss lipids too much. They do not solely strive to pack pounds onto that gorgeous frame of yours.

Proteins can do just about anything: structure, communication, defense, transport… Do not put anything past them. They’ll even write that book report for you! We kid, we kid...sort of. Proteins do help your neurons fire and allow the muscles in your hand to move while you write that brilliant masterpiece on Catcher in the Rye.

Nucleic acids, like DNA and RNA, provide the blueprint for life. They are the design architects of your body, so to speak. They store Life’s little instruction book and pass it from generation to generation.

All in all, the little tidbits of chemistry you learn here will help you to understand how all of this forthcoming biology really works. After we are done, you might even be able to set aside a little love for the study of life (bio) and the study of matter (chem). Just maybe.

Biomolecules and the Chemistry of Life Resources

Websites

Periodic Table
Interact with the periodic table like you've never interacted before. This bad boy has information on everything from an element's melting point to its half-life. There are even handy dandy links to the elements' Wikipedia pages. You know, just in case you had a burning desire to learn how Berkelium got its name.

PBS Periodic Table
In case you missed out on the first periodic table, here's another interactive model. This one is brought to you by NOVA and actually lets you filter the elements by a number of different criteria, including "most abundant in pyrotechnics." We always wanted to know what fireworks were made of.

Hippocampus
This free (and cleverly named) educational website has narrated PowerPoint slides on biology basics and the chemistry of life. We apologize in advance for the narrator's voice. It can get a little...irksome.

The Structures of Life
National Institute of General Medical Sciences' website on proteins. Doesn't that sound like a party?

Natural Polymers
A website all about the wonders of natural polymers, with an emphasis on carbohydrates and proteins. Pardon the Comic Sans.

Vision Learning
An educational website funded by the National Science Foundation. We're BFFs with the NSF. The "Chemistry" tab covers a variety of topics in basic chemistry.

United States' Geological Survey
The USGS's take on what makes water important. Hint: It isn't "raditude" or "surfability."

Lipids
A Wisconsin-based website with a bit more information on lipids, including differences between monounsaturated and polyunsaturated fats. There are also pictures! Really strange pictures that may or may not haunt your dreams and make you never want to consume a Double Double from In-N-Out ever again.

Peptide Bond Formation
Wisconsin-based website with a slide show on peptide bond formation. It's the height of PowerPoint technology.

EPA Acid Rain
The Environmental Protection Agency (EPA) webpages on acid rain. We would make a joke here, but acid rain is some pretty serious stuff. In fact, we hear it was the leading contributor to the Acid Wash Jeans Epidemic of the 1980s. (Disclaimer: The previous sentence was both factually incorrect and a terrible joke. Shmoop would like to apologize for any emotional distress it may have caused you.)

Audio

The Origin of the Word Atom
An NPR segment on the origin of the word atom. A transcript is also available if you're more of a visual learner.

The Shape of an Electron
A study 12 years in the making has finally revealed the true shape of an electron: a near-perfect sphere. Looks like those Styrofoam models we made as kids were correct after all.

Proton Smaller Than We Thought?
Another NPR segment, this time on the possibility that protons are actually smaller than we previously thought. What can we say? We're NPRaholics.

Video

Bill Nye on Atoms and Molecules
We still have the theme song from Bill Nye the Science Guy memorized. That's how good it was. And they are just as relevant today as they were...well, when we were in school. You guys don't need specific dates.

The Cassiopeia Project: Carbohydrates
The Cassiopeia Project is a science resource for students and teachers alike. They make hi-def videos on all sorts of awesome subjects. We've linked to their foray into carbohydrates, but feel free to explore their YouTube channel for more.

DNA
Morgan Freeman talking about DNA. Need we say more?

Carbon Atoms Moving in Real Time
A video of individual carbon atoms in action. It's like a supercharged (ha) game of Arkanoid.

Meet the Elements
Did you know that elephants are made of elements? Learn all about this and other fun facts from one of our favorite bands, They Might Be Giants. This song is off of their album Here Comes Science.

Images

Polyethylene Foil
A microscopic photograph of polyethylene foil from the Nikon Small World competition. It reminds us of Picasso's Cubism phase.