Biomolecules Study Guide

Vocabulary flashcards covering carbohydrates, lipids, and protein structures from the notes.

Monosaccharide

A simple sugar; the most basic unit of carbohydrates (e.g., glucose).

Glucose

A six-carbon monosaccharide; primary energy source for cells.

Disaccharide

A carbohydrate formed by two monosaccharides linked by a glycosidic bond.

Sucrose

Disaccharide composed of glucose and fructose; common table sugar.

Polysaccharide

Carbohydrate polymer consisting of many monosaccharide units; can be a storage or structural form.

Starch

Plant storage polysaccharide; polymer of glucose.

Glycogen

Animal storage polysaccharide; highly branched polymer of glucose.

Cellulose

Structural polysaccharide in plant cell walls; polymer of glucose with beta linkages.

Chitin

Structural polysaccharide in arthropod exoskeletons and fungal cell walls; polymer of N-acetylglucosamine.

Glycosidic linkage

Covalent bond between two or more monosaccharides.

Triglyceride

Glycerol backbone with three fatty acids; major form of stored fat.

Glycerol

Three-carbon backbone of triglycerides and phospholipids.

Fatty acid

Hydrocarbon chain with a terminal carboxyl group; can be saturated or unsaturated.

Phospholipid

Lipid with two fatty acids and a phosphate group; forms cellular membranes.

Saturated fatty acid

Fatty acid with no double bonds between carbons.

Unsaturated fatty acid

Fatty acid containing one or more double bonds; introduces kinks.

Ester bond

Bond connecting glycerol to fatty acids in triglycerides and phospholipids.

Steroid

Lipid with four fused rings; includes cholesterol and steroid hormones.

Cholesterol

Steroid lipid; component of cell membranes; precursor to hormones.

Hormones

Chemical signaling molecules; many are steroids; regulate physiological processes.

Amino acid

Organic molecule; monomer of proteins; contains amino and carboxyl groups with an R-group.

Peptide bond

Covalent bond linking amino acids in a polypeptide chain.

Primary structure

Linear sequence of amino acids in a protein.

Secondary structure

Localized structures such as alpha-helix and beta-sheet formed by hydrogen bonding.

Tertiary structure

Overall three-dimensional folding of a protein due to interactions among R groups.

Quaternary structure

Protein structure consisting of two or more polypeptide chains.

Hemoglobin

Protein with quaternary structure that carries oxygen in the blood.