Topic 4

Question 1

Stimuli are detected by..

Answer 1

receptors that only respond to a specific stimulus

Question 2

Receptors can be .. (2 things)

Answer 2

• dendrites on a unipolar neuron

- an individual cell that synapses to a neuron

Question 3

1st thing that happens when a receptor is stimulated

Answer 3

stimulus causes opening of gated channels (usually Na) on receptor membrane

Question 4

2nd thing that happens when a receptor is stimulated

Answer 4

graded potential on receptor membrane

Question 5

How a dendrite receptor reacts to graded potential

Answer 5

dendrite of unipolar neuron and GP (deploy) directly generates an AP which equals a generator potential

Question 6

How a individual cell receptor reacts to graded potential

Answer 6

individual cell (no axon) which equals a receptor potential that goes to a nt on associated neuron, that becomes an EPSP on neuron, that then generates an AP

Question 7

2 types of receptors

Answer 7

• phasic

- tonic

Question 8

Phasic receptors

Answer 8

respond to stimulus change and in the presence of a constant stimulus show adaptation (usually descries in sensitivity)

Question 9

Example of phasic receptors

Answer 9

puts a hat on so bursts of AP (feeling it) then get descries in AP frequency to CNS (can’t feel it) even though stimulus maintained at constant strength

Question 10

Tonic receptors

Answer 10

frequency of APs remain constant (NO adaptation) give continuous info, and monitors presence and intensity of stimulus

Question 11

How does brain perceive different types of stimuli

Answer 11

mainly by type of receptor stimulated

Question 12

When an axon is activated by a receptor the brain then…

Answer 12

then synaptic connections to part of CNA concerned wirth that sense (who’s calling (receptor) and from where (location))

Question 13

How does brain perceive stimuli of different strengths

Answer 13

mainly by frequency of AP going to CNS, the stronger stimulus also activated more receptors