AP Biology Unit 1: The Chemistry of Macromolecules

Macromolecules

Large biological molecules, including carbohydrates, lipids, proteins, and nucleic acids.

Polymers

Chain-like molecules made up of many similar or identical building blocks linked by covalent bonds.

Monomers

Smaller molecules that serve as the building blocks of polymers.

Dehydration Synthesis

A reaction that connects monomers to form polymers, resulting in the loss of a water molecule.

Hydrolysis

A reaction that breaks down polymers into monomers, involving the addition of a water molecule.

Carbohydrates

Sugars and polymers of sugars with a general formula of $CH_2O$.

Monosaccharides

The simplest sugars, serving as major fuel for cells, such as glucose.

Disaccharides

Two monosaccharides joined by a glycosidic linkage.

Polysaccharides

Polymers of sugars that have storage and structural functions.

Starch

A storage polysaccharide in plants, composed of $eta$-glucose monomers.

Glycogen

A storage polysaccharide in animals, highly branched, used for energy storage.

Cellulose

A structural polysaccharide composed of $eta$-glucose monomers, a major component of plant cell walls.

Chitin

A structural carbohydrate with nitrogen, found in exoskeletons of arthropods.

Lipids

Macromolecules that are hydrophobic and do not form true polymers.

Triglycerides

Fats constructed from glycerol and fatty acids.

Saturated Fatty Acids

Fatty acids with no double bonds between carbon atoms, solid at room temperature.

Unsaturated Fatty Acids

Fatty acids containing one or more double bonds, liquid at room temperature.

Phospholipids

Molecules essential for cell membranes, composed of two fatty acids and a phosphate group.

Steroids

Lipids characterized by a carbon skeleton with four fused rings, such as cholesterol.

Proteins

Polymers of amino acids that perform a vast array of functions in organisms.

Amino Acids

Monomers of proteins, consisting of an amino group, carboxyl group, hydrogen atom, and variable R group.

Peptide Bonds

Covalent bonds that link amino acids together to form polypeptides.

Primary Structure

The unique sequence of amino acids in a protein, determined by genetic information.

Secondary Structure

Coils (alpha helix) and folds (beta pleated sheet) in a polypeptide chain due to hydrogen bonding.

Tertiary Structure

The overall three-dimensional shape of a polypeptide formed by side chain interactions.

Quaternary Structure

The structure formed when two or more polypeptide chains aggregate into a functional protein.

Nucleic Acids

Polymers that store, transmit, and help express hereditary information.

Nucleotides

Monomers of nucleic acids, composed of a sugar, a nitrogenous base, and phosphate groups.

Phosphodiester Linkage

The bond connecting nucleotides in a polynucleotide.