The key thing to remember is that biochemistry is the chemistry of the living world. Plants, animals, and single-celled organisms all use the same basic chemical compounds to live their lives. Biochemistry is not about the cells or the organisms. It's about the smallest parts of those organisms, the molecules. It's also about the cycles that create those biological compounds.

Every cycle has a place, and each one is just a small piece that helps an organism survive. In each cycle, molecules are used as reactants and then transformed into products. Life is one big network of activity where each piece relies on all of the others. A compound, such as an herbicide, may only break one part of one cycle in a plant. However, because everything needs to work together, the whole plant eventually dies.

We like biochemistry because we learn about things that are inside of us. We can relate to what happens when we eat and how our bodies are constructed. We can imagine how the molecules are moving around the mitochondria or chloroplasts, as opposed to chemical changes that make natural gas. If you choose a career in biology or chemistry, you will need to understand the information in both biochemistry and organic chemistry. Why? Because the movement of atoms in the bio-chem world follows the same rules you will learn in o-chem.

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Chem4Kids.com: Biochemistry