P-words

Question 1

paracrine communication

Answer 1

when the signal reaches the target cell via the interstitial space

Question 2

paravertebral ganglia

Answer 2

chain of ganglia connected with nerve trunks along the spinal cord that contains sympathetic postganglionic neurons

Question 3

peptide

Answer 3

short protein molecule

Question 4

peptide bond

Answer 4

a covalent bond linking two consecutive amino acid monomers along a peptide or protein chain

Question 5

peripheral (extrinsic) protein

Answer 5

protein located at the internal or external surface of the cell membrane

Question 6

permeability

Answer 6

ability of a compound to cross the membrane; it depends on the characteristics of the compound and of the membrane

Question 7

phagocyte

Answer 7

cells that protect the body by ingesting harmful foreign particles, bacteria and dead or dying cells

Question 8

phagocytosis

Answer 8

forms of endocytosis to take up solid particles or fluid into the cell

Question 9

phosphoglyceride

Answer 9

glycerol-based phospholipid, main component of biological membranes

Question 10

phospholipid

Answer 10

phosphorus-containing lipid

Question 11

phosphorylation

Answer 11

incorporation of a phosphate group into an organic molecule

Question 12

plateau

Answer 12

characteristic period in the action potential of the heart muscle cell, when the membrane potential is relatively constant

Question 13

pneumothorax

Answer 13

collapse of a lung due to a puncture that penetrates the pleural cavity

Question 14

Poiseuille’s law

Answer 14

equation describing the laminar flow of fluids in rigid tubes as the function of pressure difference, tube diameter and length, and viscosity

Question 15

polar

Answer 15

a polar molecule has a net dipole as a result of the opposing charges from polar bonds arranged asymmetrically

Question 16

polypnea

Answer 16

rapid breathing

Question 17

polysaccharides

Answer 17

macromolecules built up by simple sugar molecules

Question 18

postganglionic neuron

Answer 18

autonomic neuron located in a peripheral ganglion that receives input from preganglionic neurons and synapses onto target organs

Question 19

posttetanic potentiation

Answer 19

increased efficacy of synaptic transmission following presynaptic stimulation at a high frequency

Question 20

precapillary sphincter

Answer 20

muscular ring at the origin of capillaries regulating blood flow in the capillary

Question 21

preganglionic neuron

Answer 21

autonomic neuron located in the central nervous system that sends an axon into the periphery and synapses onto postganglionic cells

Question 22

pressor area (center)

Answer 22

area in the dorsolateral reticular formation of the medulla; its excitation increase heart rate, constrict vessels, thus increases blood pressure through sympathetic fibers

Question 23

primary structure of proteins

Answer 23

sequence of amino acids building up the molecule

Question 24

projection neuron

Answer 24

nerve cell with a long axon running to remote targets

Question 25

protein

Answer 25

macromolecule built up by amino acids

Question 26

protein kinase

Answer 26

enzyme catalyzing the transfer of a phosphate group from ATP to a protein

Question 27

pseudounipolar neuron

Answer 27

nerve cell with one process that branches near to the soma forming two equivalent neurits

Question 28

pulse volume

Answer 28

volume of blood pumped by the heart into the circulation during one systole

Question 29

purines

Answer 29

compounds based on a two-ring structure with 5 C and 4 N atoms; adenine and guanine

Question 30

Purkinje fibers

Answer 30

specialized conducting fibers in the heart that can conduct cardiac APs more quickly and efficiently than any other cells in the heart

Question 31

pyrimidines

Answer 31

compounds based on a ring containing 4 C and 2 N atoms; uracil, thymidine and cytosine