AP Bio Chapter 5

Macromolecule

A very large molecule formed from many smaller subunits.

Monomer

A small molecular unit that can be linked to form a polymer.

Polymer

A large molecule composed of many repeating monomer subunits.

Amino acid

The monomer subunit that links together to build proteins and polypeptides.

Peptide bond

The specific chemical bond that connects one amino acid to another.

Enzyme

A protein that acts as a catalyst to speed up a chemical reaction.

Primary structure

The specific sequence of amino acids in a protein.

Secondary structure

The folding or coiling of the amino acid chain into alpha helices or beta sheets.

Dehydration/Condensation Reaction

A chemical reaction that links monomers together by removing a water molecule.

Hydrolysis

A chemical reaction that breaks polymers apart by adding a water molecule.

Alpha helix

A spiral-shaped form of the secondary structure in proteins.

Carbohydrate

A molecule composed of sugar units used for energy or structural support.

Beta pleated sheet

A folded sheet-like form of the secondary structure in proteins.

Monosaccharide

The simplest form of sugar and the basic unit of carbohydrates.

Tertiary structure

The overall 3D shape of a protein caused by interactions between side chains.

Disaccharide

A carbohydrate made of two monosaccharides linked by a glycosidic bond.

Hydrophobic interaction

A type of interaction that helps proteins fold by avoiding water.

Glycosidic linkage

The covalent bond formed between two sugar molecules in a carbohydrate.

Disulfide bridge

A strong covalent bond formed between sulfur atoms in two amino acids.

Oligosaccharide

A carbohydrate made of a few (typically 3-10) monosaccharides.

Quaternary structure

The structure formed when multiple polypeptide chains join to make a functional protein.

Polysaccharide

A long chain of sugar molecules, often used for energy storage or structure.

Sickle cell disease

A genetic disorder caused by a mutation in the hemoglobin protein.

Starch

A storage polysaccharide in plants made of glucose.

Denaturation

The process where a protein loses its specific shape and becomes non-functional.

Glycogen

A storage polysaccharide in animals made of glucose.

Chaperonins

Proteins that assist in the proper folding of other proteins.

Cellulose

A structural polysaccharide in plant cell walls made of glucose.

Chitin

A structural polysaccharide found in the exoskeletons of arthropods and cell walls of fungi.

Gene

A segment of DNA that codes for a specific protein.

Lipid

A diverse group of nonpolar, water-fearing molecules like fats and oils.

Nucleic acid

A macromolecule made of nucleotide chains that store genetic information.

Fat

A type of lipid used for long-term energy storage and insulation.

DNA

A nucleic acid that stores genetic information in cells.

Fatty acid

A hydrocarbon chain with a carboxyl group, found in fats and phospholipids.

RNA

A nucleic acid that helps in protein synthesis and carries genetic information in some viruses.

Saturated fatty acid

A fatty acid chain with no double bonds, making it solid at room temperature.

Polynucleotide

A polymer made of many nucleotide monomers.

Unsaturated fatty acid

A fatty acid chain with one or more double bonds, making it liquid at room temperature.

Nucleotide

The monomer subunit of nucleic acids, consisting of a sugar, phosphate, and nitrogen base.

Trans fat

An unsaturated fat with trans double bonds, often artificially produced.

Pyrimidine

A nitrogenous base with a single ring, such as cytosine, thymine, or uracil.

Phospholipid

A lipid with a phosphate group, forming the main component of cell membranes.

Purine

A nitrogenous base with a double ring, such as adenine or guanine.

Steroid

A type of lipid with four fused carbon rings, including hormones like testosterone.

Deoxyribose

The sugar found in DNA nucleotides.

Cholesterol

A steroid that is a key component of cell membranes and precursor of other steroids.

Ribose

The sugar found in RNA nucleotides.

Catalyst

A substance that increases the rate of a chemical reaction without being consumed.

Double helix

The two-stranded, twisted-ladder shape of the DNA molecule.

Polypeptide

A chain of amino acids linked by peptide bonds.

Antiparallel

Describes the opposite orientation of the two strands of DNA in the double helix.