Biology

Question 1

synapses can be both…

Answer 1

chemical and electrical

Question 2

inhibitory synapses cause the release of….

Answer 2

neurotransmitters that cause an influx of negative ions or an efflux of positive ions leading to hyper polarization, inhibiting the action potential

Question 4

Multiple sclerosis is a

Answer 4

neurodegenerative disease in which immune cells attack the myelin sheaths surrounding axons in the central nervous system (CNS).

Question 5

Huntington’s disease

Answer 5

is an autosomal dominant genetic neurodegenerative disease in which neuronal loss occurs in extensive regions of the brain, including the basal ganglia.

Question 6

in the CNS, gray matter is composed of

Answer 6

neuronal cell bodies

Question 7

in the CNS, white matter is composed of

Answer 7

axons that allow long-distance communication between neurons

Question 8

In the white matter of the spinal cord, afferent axons carry

Answer 8

sensory information to the brain

Question 9

in the white matter of the spinal cord, efferent axons carry

Answer 9

motor commands to the body.

Question 10

the glial cells of the CNS are

Answer 10

oligodendrocytes, astrocytes and ependymal cells, microglia

Question 11

oligodendrocytes

Answer 11

form myelin sheaths around axons to reduce ion leakage and increase action potential propagation speed

Question 12

astrocytes

Answer 12

support, blood-brain barrier, interstitial space

Question 13

ependymal cells

Answer 13

epithelial cells that line the compartments of the CNS and secrete CSF

Question 14

Glial cells in the PNS

Answer 14

Schwann cells (myelin)

satellite cells (structural support + nutrients to near cell bodies)

Question 15

microghlia

Answer 15

macrophages of the CNS

Question 16

the blood brain-barrier is composed of

Answer 16

endothelial cells held together by tight junctions to regulate transport through four routes

Question 17

route 1 to BBB

Answer 17

paracellular transport (between cells) is limited for hydrophilic molculces

Question 18

route 2 to BB

Answer 18

transcellular route will allow small, lipophilic molecules in by passive transport (diffusion), including

non polar gases (e..g diatomic, CO2)

steroid hormones

Question 19

route 3 to BBB

Answer 19

carrier-mediated transport which uses facilitated diffusion and active transport allows large or hydrophilic molecules like amino acids or nucleosides

Question 20

route 4 to BBB

Answer 20

through endocytosis to transport molecules in bulk

Question 21

aldosterone

Answer 21

secreted by the adrenal cortex, increases na absorption to increase water retention in the kidneys to increase blood pressur/volume

Question 22

norepinephrine and epinerine from the adrenal medulla

Answer 22

mobilize body under extreme stress including changes to blood vessel diameter

Question 23

vasoconstriction

Answer 23

higher BP but lower nutrients delivered to tissues

Question 24

vasoconstriction

Answer 24

lower BP but more nutrients delivered to tissues

Question 25

adrenal cortex makes

Answer 25

steroid hormonesad

Question 26

adrenal medulla

Answer 26

makes peptide hormones

Question 27

an endogenous substance is

Answer 27

one that is produced in the body e.g. endogenous cortisol

Question 28

myelin sheath has nodes of ranvier where charges can leak across the swath and back into the extracellular space.

Question 29

when AP flows down from node to node

Answer 29

saltatory conduction