Biomolecules and the Chemistry of Life - Shmoop 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.