AP Biology Unit 1: Chemistry of Life Summary

What is the chemical formula of water?

H2O

Why is water considered a polar molecule?

Because of the uneven distribution of charge, with oxygen having a partial negative charge and hydrogen having a partial positive charge.

What are the three main properties of water that are important for biological systems?

Cohesion, adhesion, and surface tension.

What term describes the attraction between water molecules?

Cohesion.

What role does nitrogen play in biological molecules?

Nitrogen is a component of nucleic acids and proteins.

What are the six most common elements found in living organisms?

Carbon, Hydrogen, Nitrogen, Oxygen, Phosphorus, and Sulfur (abbreviated as CHNOPS).

What process is used to join monomers to form a polymer in biological macromolecules?

Dehydration synthesis.

Which biological macromolecules are formed from amino acid monomers?

Proteins.

What bond is formed between two amino acids when they link together?

Peptide bond.

What are the two main types of nucleic acids?

DNA and RNA.

What is the key difference in sugars between RNA and DNA?

RNA contains ribose, while DNA contains deoxyribose.

How do the nitrogenous bases bond in DNA?

Adenine pairs with Thymine (or Uracil in RNA) with two hydrogen bonds, and Guanine pairs with Cytosine with three hydrogen bonds.

What type of reaction adds water to break a polymer into monomers?

Hydrolysis reaction.

What are lipids and how do they differ from carbohydrates?

Lipids are hydrophobic molecules that do not have a true monomer and have a higher ratio of hydrogen to oxygen compared to carbohydrates.

What is the primary function of carbohydrates in living organisms?

To serve as a primary source of chemical energy and to provide structural support.

What is the unique structure of a phospholipid?

Phospholipids have two hydrophobic fatty acid tails and a hydrophilic phosphate group head.

What is metabolic pathways in an organism?

The sum of all chemical reactions that take place within an organism.

What happens to proteins when they denature?

Their structure is altered, which directly affects their function.

What do the terms 'anabolic' and 'catabolic' refer to in metabolism?

Anabolic refers to reactions that build molecules, while catabolic refers to reactions that break down molecules.

What is a macromolecule?

A large, complex molecule, such as carbohydrates, proteins, lipids, and nucleic acids, that is essential to biological functions.

How many different amino acids can be combined to form proteins?

Twenty different amino acids.