Ch. 3 Key Terms Flashcards
alpha-helix structure (α-helix)
type of secondary protein structure formed by folding the polypeptide into a helix shape with hydrogen bonds stabilizing the structure
amino acid
a protein’s monomer; has a central carbon or alpha carbon to which an amino group, a carboxyl group, a hydrogen, and an R group or side chain is attached; the R group is different for all 20 common amino acids
beta-pleated sheet (β-pleated)
secondary structure in proteins in which hydrogen bonding forms “pleats” between atoms on the polypeptide chain’s backbone
biological macromolecule
large molecule necessary for life that is built from smaller organic molecules
carbohydrate
biological macromolecule in which the ratio of carbon to hydrogen and to oxygen is 1:2:1; serves as energy sources and structural support in cells and form arthropods’ cellular exoskeleton
cellulose
polysaccharide that comprises the plants’ cell wall; provides structural support to the cell
chaperone
protein that helps nascent protein in the folding process
dehydration synthesis
(also, condensation) reaction that links monomer molecules, releasing a water molecule for each bond formed
denaturation
loss of shape in a protein as a result of changes in temperature, pH, or chemical exposure
deoxyribonucleic acid (DNA)
double-helical molecule that carries the cell’s hereditary information
disaccharide
two sugar monomers that a glycosidic bond links
enzyme
catalyst in a biochemical reaction that usually a complex or conjugated protein
glycogen
storage carbohydrate in animals
glycosidic bond
bond formed by a dehydration reaction between two monosaccharides with eliminating a water molecule
horomone
chemical signaling molecule, usually protein or steroid, secreted by endocrine cells that act to control or regulate specific physiological processes
hydrolysis
reaction that causes breakdown of larger molecules into smaller molecules by utilizing water
lipid
macromolecule that is nonpolar and insoluable in water
messenger RNA (mRNA)
RNA that carries information from DNA to ribosomes during protein synthesis