Encyclopedia of Biology

sensory-somatic nervous system and the autonomic nervous system. periplasm The fluid occupying the space between the inside and ...

sary to ensure the optimal supramolecular interactions with a specific biological target structure and to trigger (or to block) ...

A1hydrolyzes the acyl group attached to the 1-posi- tion, while phospholipase A2 hydrolyzes the acyl group attached to the 2-pos ...

photosystem A membrane-bound protein complex in plants and photosynthetic bacteria, responsible for light harvesting and primary ...

andovaries/testes) that secrete their hormones to the blood. The pituitary gland stimulates the secretion of these hormones, but ...

plasma Inbiology, this term has the following three meanings: Fluid component of blood in which the blood cells and platelets a ...

ments (folding, twisting, coiling) of polypeptide chains in a protein. They can be in the form of a helix, ran- dom coil, or ple ...

called Rhus toxicodendron. Western poison oak is known as Toxicodendron diversilobum. These plants can cause a skin reaction. No ...

polygenic inheritance The interaction of several genes on a phenotype trait. A series of genes at multiple lociwhere each contri ...

polyp A cnidarian body form that is the sessile reproductive stage; the alternate is the mobile medusa stage. In medicine, a pol ...

potency A comparative rather than an absolute expression of drug activity. Drug potency depends on bothAFFINITYand EFFICACY. Thu ...

primordial germ cells Fetal cells that develop in the early fetus and that will develop into the gametes, the male sperm or fema ...

prophase During prophase, the chromosomes are identical chromatids that are connected at the center by a centromere (x-shaped). ...

amino acids pleated sheet pleated sheet alpha helix alpha helix Primary protein structure is a sequence of a chain of amino acid ...

tein kinase phosphorylates a protein, using ATP, and the phosphorylation modulates the shape and activity ofproteins. Protein ki ...

blastopore becomes a mouth and who have spiral and determinate cleavage. protozoan Thesimplest forms of animal life, con- sistin ...

pterin 2-amino-4-hydroxypteridine. See alsoMOLYBDOPTERIN. punctuated equilibrium A part of evolutionary theory that states that ...

quadruped An animal that moves using four-footed locomotion; moves using all four limbs. quantitative character(polygenic charac ...

queen substance A pheromone secreted by queen bees and given to worker bees that controls them from producing more queens. quies ...

raceme An inflorescence, a flower structure, in which stalked flowers are borne in succession along an elongate axis, with the y ...