Chapter 3.txt

Organic compound having one or more hydroxyl groups that dissolves easily in water; e.g., ethanol.

A small organic compound with a carboxylic acid group, an amino group, and a characteristic side group (R); monomer of polypeptide chains.

Adenosine triphosphate. A type of nucleotide that functions as the main energy carrier between reaction sites in cells. Consists of the base adenine, the five-carbon sugar ribose, and three phosphate groups.

Any molecule of carbon, hydrogen, and oxygen typically in a 1:2:1 ratio. Main kinds are monosaccharides, oligosaccharides, and polysaccharides. They serve as structural materials, energy stores, and transportable energy forms.

An organic molecule that is a necessary participant in some enzymatic reactions; helps catalysis by donating or accepting electrons or functional groups; e.g., a vitamin, ATP, NAD+.

Type of chemical reaction in which two molecules become covalently bonded as a larger molecule; water often forms as a by-product.

Disruption of hydrogen bonds and other interactions holding a molecule in its three-dimensional shape, which thereby changes. Increases in temperature, shifts in pH, and detergents can cause it.

[Gk. di, two, + sakcharon, sugar] A carbohydrate composed of two sugar monomers.

Deoxyribonucleic acid. Double-stranded nucleic acid twisted into a helical shape; its base sequence encodes the primary hereditary information for all living organisms and many viruses.

A type of protein that catalyzes (speeds) a chemical reaction. Some RNAs also show catalytic activity.

Type of lipid with one, two, or three fatty acid tails attached to a glycerol head.

Organic compound having a carboxyl group and a backbone of as many as thirty-six carbon atoms; saturated types have single bonds only; unsaturated types include one or more double covalent bonds.

An atom or a group of atoms with characteristic properties that is covalently bonded to the carbon backbone of an organic compound.

Highly branched polysaccharide of glucose monomers; the main storage carbohydrate in animals.

Protein with linear or branched oligosaccharides covalently bonded to it.

[Gk. haima, blood, + L. globus, ball] A hemecontaining protein produced by red blood cells; carries most of the oxygen in blood.

Organic compound with only hydrogen bonded to its carbon backbone.

[L. hydro, water, + Gk. lysis, loosening] A cleavage reaction; an enzyme splits a molecule, then the components of water (�OH and �H) are attached to the fragments.

One of the nonpolar hydrocarbons; e.g., a fat, oil, wax, sterol, phospholipid, or glycolipid. Cells use as storage forms of energy and building blocks.

A protein complexed with cholesterol, triglycerides, or phospholipids that were absorbed from the small intestine.

Any small molecule that is a repeating subunit in a polymer; e.g., the sugar monomers of starch.

[Gk. monos, alone, single, + sakcharon, sugar] A simple sugar.

Single-stranded or doublestranded molecule of nucleotides joined at phosphate groups; e.g., DNA, RNA.

Small organic compound with a five-carbon sugar, a nitrogen-containing base, and a phosphate group. Functions as coenzymes or monomers of nucleic acids.

Short-chain carbohydrate of two or more covalently bonded sugar monomers; e.g., sucrose and other disaccharides.

Any carbon-based molecule that also incorporates atoms of hydrogen and, often, oxygen, nitrogen, and other elements; e.g., fats, proteins.

The chemical bond formed between the carboxyl groups and amino groups of neighboring amino acids, constituting the primary linkage of all protein structures.

A lipid with a phosphate group in its hydrophilic head. The main constituent of cell membranes.

Large molecule of multiple linked monomers.

Three or more amino acids linked by peptide bonds.

[Gk. polus, many, + sakcharon, sugar] Straight or branched chain of covalently bonded monomers of the same or different kinds of sugars; e.g., cellulose, starch, and glycogen.

Organic compound consisting of one or more polypeptide chains. Diverse kinds have structural, functional, and regulatory roles in all organisms.

Ribonucleic acid. Any of a class of single-stranded nucleic acids involved in gene transcription and translation; some RNAs show enzyme activity.

Any lipid consisting of a rigid backbone of four fused carbon rings.

A lipid with three fatty acid tails attached to a glycerol backbone.

A lipid with long-chain fatty acids attached to an alcohol other than glycerol.