Unit 1 - AP Bio

What are the 4 major macromolecules?

Carbohydrates, lipids, proteins, and nucleic acids

What is a dehydration (condensation) reaction?

A reaction that joins two monomers by removing a water molecule, forming a covalent bond (e.g. peptide bonds, glycosidic bonds)

What is hydrolysis?

The breakdown of a polymer by adding water across a bond, separating monomers

What are the monomers of Carbohydrates?

Monosaccharides (e.g. glucose, fructose). Polysaccharides like starch, glycogen, and cellulose are built from them.

How do starch, glycogen, and cellulose differ?

Starch (plant energy storage) and glycogen (animal energy storage) use a-glucose with glycosidic bonds; cellulose (plant cell walls) use b-glucose, making it indigestible

What are the monomers of proteins?

Amino acids, linked by peptide bonds. A protein’s function depends on its unique sequence and 3D shape

Describe the 4 levels of protein structure

Primary: amino acid sequence. Secondary: alpha helix & beta sheets (h-bonds). Tertiary: overall 3D fold. Quaternary: multiple polypeptide chains.

What causes proteins denaturation?

Disruption of bonds by heat, extreme pH, or chemicals, altering the protein’s shape and destroying its function

What are the monomers of nucleic acids?

Nucleotides, each composed of a phosphate group, a 5-carbon sugar (ribose or deoxyribose), and a nitrogenous base.

How do DNA and RNA differ structurally?

DNA: double-stranded. deoxyribose sugar, bases ATGC. RNA: single stranded, ribose sugar, bases AUGC

What are saturated vs. unsaturated fats?

Saturated: no double bonds in fatty acid tails, solid at room temp. Unsaturated: one or more double bonds, liquid at room temp (oils).

Why is water a polar molecules?

Oxygen is more electronegative than hydrogen, creating partial negative (O) and positive (H) charges, enabling hydrogen bonding.

What are the key properties of water?

Cohesion, adhesion, high specific heat, high heat of vaporization, solvent properties, and lower density as ice expands when frozen

What does pH measure?

The concentration of H+ ions in a solution. pH < 7 = acidic, pH 7 = neutral, pH > 7 = basic