Chapter 2 - Proteins

Protein

macromolecule made of amino acids; used for structure, movement, transport, enzymes, etc.

Amino Acid

the monomer (building block) of proteins (ex: 20 different types).

What determines a protein’s function?

its shape / 3D structure.

Peptide Bond

bond that links amino acids together.

Primary Structure

sequence (order) of amino acids.

Secondary Structure

folding patterns like alpha helices and beta sheets.

Tertiary Structure

full 3D folding shape of one polypeptide.

Quaternary Structure

multiple polypeptides interacting (ex: hemoglobin).

What happens if a protein denatures?

it loses shape → loses function.

Enzyme

protein that speeds up chemical reactions by lowering activation energy.

What is the active site?

specific region on an enzyme where the substrate binds.

What affects enzyme activity?

temperature, pH, substrate concentration.

Substrate

the molecule an enzyme acts on.

Why are proteins so diverse?

20 amino acids can combine in endless different sequences.