A-words

Question 1

Actin and myosin

Answer 1

proteins responsible for muscle contraction

Question 2

Active transport

Answer 2

energy requiring translocation of a substance across the membrane against its electrochemical gradient

Question 3

Afterhyperpolarization

Answer 3

hyperpolarization following an action potential

Question 4

Agonist

Answer 4

a substance that has the same effect on a receptor as a mediator or transmitter

Question 5

Albumin

Answer 5

largest protein fraction in the blood plasma, mainly responsible for the colloid osmotic pressure of the plasma

Question 6

Aldo-sugar

Answer 6

sugar containing an aldehyde group, e.g. glucose, galactose

Question 7

All-or-none-response

Answer 7

regardless of the amplitude of the stimulus, if the stimulus reaches threshold and action potential will follow

Question 8

Arteriole

Answer 8

muscular vessels connecting arteries and capillaries

Question 9

Autoimmune disease

Answer 9

erroneous immune response of an organism against its own proteins or macromolecules

Question 10

ATP

Answer 10

adenosine triphosphate, molecule used as an energy source by all cells

Question 11

Atrium

Answer 11

chamber in the heart where venous blood returns

Question 12

Axon

Answer 12

long projection of a neuron that typically conducts electrical impulses away from the soma

Question 13

Axonal transport

Answer 13

transport mechanism of the axon that transports substances toward the soma and axonal terminals

Question 14

Antagonist

Answer 14

a substance that stops the effect of a mediator or transmitter on a receptor

Question 15

Alpha helix

Answer 15

the coiled structure of many proteins consisting of a single chain of amino acids stabilized by hydrogen bonds

Question 16

Alveoli

Answer 16

unit of the lung where gases are exchanged, through the alveoli walls

Question 17

Antigen

Answer 17

any substance that will cause an immune response that produces antibodies against it

Question 18

Antibody

Answer 18

protein molecule produced by lymphocytes that specifically binds to antigens

Question 19

Apnea

Answer 19

suspension or absence of breath

Question 20

Annulus fibrous

Answer 20

sheet of connective tissue separating the atria from ventricles and providing anchoring points for the valves

Question 21

Arteriovenous oxygen difference

Answer 21

difference in the partial pressure of oxygen in arterial and venous blood flowing to and from organs

Question 22

Atrioventricular node

Answer 22

specialized conduction tissue in the heart located at the border of the right atrium and ventricle

Question 23

Arteriovenous anastomosis

Answer 23

short vessels connecting arterioles and venules, found especially in the skin

Question 24

Alpha carbon atom

Answer 24

C-atom closest to the carboxyl group in organic acids

Question 25

Anisotropic substance

Answer 25

differentially transparent to polarized light depending on the plane of light