Biology Phospholids-Proteins

Phospholipids

Major component of cell membranes composed of 1 glycerol, 2 fatty acids, and a phosphate group.

Steroids

Lipids where the carbon skeleton contains four fused rings with varying functional groups.

Cholesterol

A common component in animal cell membranes, used for making other steroids like sex hormones.

Amino acids

Monomers that make up proteins, containing an NH2 group, COOH group, hydrogen, central carbon, and an R group.

Peptide bond

Covalent bond formed between two amino acids when they join together.

Dipeptide

A molecule consisting of two amino acids linked by a peptide bond.

Polypeptide

A chain of many amino acids linked by peptide bonds.

Denaturation

The process where a protein's structure unravels due to high heat, wrong pH, or wrong salinity.

Primary structure of a protein

The precise sequence of amino acids in a polypeptide chain, determined by genetic code.

Secondary structure of a protein

The folding or pleating of the primary structure, maintained by hydrogen bonds.

Tertiary structure of a protein

The overall 3D shape caused by interactions of R groups in the protein.

Quaternary structure of a protein

Proteins that consist of more than one polypeptide chain.

Enzymes

Proteins that act as catalysts to speed up chemical reactions.

Globular proteins

Proteins that have a rounded shape and are often water-soluble.

Fibrous proteins

Proteins that have elongated shapes and are generally insoluble in water.

Functions of proteins

Act as enzymes, transport molecules, aid in defense, serve as signals, act as cell receptors, aid in movement and store amino acids.