Molecules, hormones & receptors Flashcards
What is an α helix?
A coiled secondary structure of a polypeptide chain formed by hydrogen bonding between amino acids separated by four residues.
What is a β sheet?
A sheetlike secondary structure of a polypeptide chain, formed by hydrogen bonding between amino acids located in different regions of the polypeptide.
What is a carbohydrate?
A molecule with the formula (CH2O)n. Carbohydrates include both simple sugars and polysaccharides.
What is cellulose?
The principal structural component of the plant cell wall, a linear polymer of glucose residues linked by β(1→4) glycosidic bonds.
What is cholesterol?
A lipid consisting of four hydrocarbon rings. Cholesterol is a major constituent of animal cell plasma membranes and the precursor of steroid hormones.
What is deoxyribonucleic acid (DNA)?
The genetic material of the cell.
What are fatty acids?
Long hydrocarbon chains usually linked to a carboxyl group (COO-).
What is glycogen?
A polymer of glucose residues that is the principal storage form of carbohydrates in animals.
What is a glycosidic bond?
The bond formed between sugar residues in oligosaccharides or polysaccharides.
What are lipids?
Hydrophobic molecules that function as energy storage molecules, signaling molecules, and the major components of cell membranes.
What is osmotic pressure?
The pressure exerted by the flow of water through a semipermeable membrane separating two solutions with different concentrations of solute.
What is osmolarity?
The osmotic pressure of a solution expressed in osmoles or milliosmoles per liter of the solution.
What is a peptide bond?
The bond joining amino acids in polypeptide chains.
What is pH?
A measure of the acidity or alkalinity of a solution, numerically equal to 7 for neutral solutions, increasing with increasing alkalinity and decreasing with increasing acidity.
What is a phosphodiester bond?
A bond between the 5’-phosphate of one nucleotide and the 3’-hydroxyl of another.
