produced when the angle between the bones of a joint changes

negative ion that is formed by an atom gaining one or more electrons

phylum of vermiform animals with metamerism

without oxygen

pigment molecule that directly absorbs light and transfers the energy absorbed to other pigment molecules

portion of the pituitary gland that produces six hormones; also called adenohypophysis

sac-like structure at the tip of the stamen in which pollen grains are produced

male gametangium

phylum to which angiosperms belong

monkeys, apes, and humans

hormone that prevents the loss of water

biological substance that, in low concentration, is antagonistic to the growth of prokaryotes

ability of an organism to be unaffected by an antibiotic's actions

protein that is produced by plasma cells after stimulation by an antigen; also known as an immunoglobulin

three-nucleotide sequence in a tRNA molecule that corresponds to an mRNA codon