To Learn Human Organism

Question 1

optimal functioning

Answer 1

variables are kept in homeostatic range

Question 2

cell excitability

Answer 2

ability of cell to generate electrical signals in response to stimulus

Question 3

soma

Answer 3

body of neuron

Question 4

axon

Answer 4

cable that conducts electricity away from dendrites

Question 5

dendrites

Answer 5

receive information

Question 6

myelin sheath

Answer 6

lipid that surrounds axon, insulator to make quicker E impulse

Question 7

afferent neurons

Answer 7

sensory neurons, pass info from tissue + organs to CNS

Question 8

efferent neurons

Answer 8

motor neurons, pass info from CNS to effector cells

Question 9

interneurons

Answer 9

connect neurons

Question 10

resting membrane potential

Answer 10

voltage in non-signaling cells,
- 60 to -90 mv

Question 11

depolarisation

Answer 11

quick shift of membrane potential from negative to positive

Question 12

absolute refractory period

Answer 12

between depolarisation + repolarisation
- neuron can’t react to new stimulus until it returns to resting membrane potential

Question 13

repolarisation

Answer 13

• after depolarisation
• potassium moves out of cell + voltage gates sodium ion channel closes
• cell approaches resting membrane potential

Question 14

hyperpolarisation

Answer 14

cell becomes more negative than resting membrane potential

Question 15

relative refractory period

Answer 15

stronger stimulus needed to activate neuron

Question 16

electrical synapse

Answer 16

passes E signals through gap junctions
- fast
- bidirectional
- less complex

Question 17

chemical synapse

Answer 17

E activity converted to release neurotransmitters

Question 18

synaptic weight

Answer 18

strength of firing from neuron

Question 19

neurotransmitters

Answer 19

signaling molecule secreted by neurons to affect another neuron across synapse

Question 20

mechanisms of removing neurotransmitters

Answer 20

1. diffusion
2. reuptake
3. degradation
4. uptake by astrocytes

Question 21

biogenic amine neurotransmitters

Answer 21

histamine, serotonin, dopamine, epinephrine, acetylcholine

Question 22

enzymes that inactivate neurotransmitters

Answer 22

MAO + COMT

Question 23

MAO

Answer 23

inactivates serotonin, dopamine, epinephrine + norepinephrine

Question 24

COMT

Answer 24

inactivates dopamine, epinephrine, norepinephrine

Question 25

glia cells

Answer 25

non neuron cells in CNS

Question 26

glial cells functions

Answer 26

nutrients
myelin sheaths
neurogeneration
destroy pathogens
remove dead cells