Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biology Module 5 > Neuronal communication 5.3 > Flashcards

Neuronal communication 5.3 Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

what are receptors

A

cells or proteins that can detect a specific stimulus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what are transducers

A

convert the energy of the stimulus to electrical energy by creating an electrochemical gradient

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

potassium ion channels allow what to happen?

A

facilitated diffusion allows k+ ions to move down the conc. gradient

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

the bigger the stimulus the….

A

…..more larger the voltage change is
if change is big enough, causes an action potential (impulse)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

describe what is action potential

A

if threshold level is reached
wave of depolarisation is created along the neuron
- electrical impulse

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what is the ‘all or nothing principle’

A

action potential only happens if the stimulus is strong, if its weak no action potential is produced.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what is the first step of generation and transmission of signal

A

stimulus
triggers opening of Na+ channels
permeability to Na+ ions increases
Na+ diffuses INTO neurone
inside of neurone is less negative
(electrochemical gradient)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what is the second step of generation and transmission of a signal

A

depolarisation
if P.D reaches threshold value -50 mV
voltage gated sodium ion channels open
more sodium ions diffuse in
(positive feedback)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what is the third step of generation and transmission of a signal

A

repolarisation
at P.D of +30mV
sodium ion channels close
voltage gated potassium ion channels open
permeablity to K+ ions increase
K+ ion diffuse OUT
(negative feedback)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what is the fourth step of generation and transmission of signals

A

hyperpolarisation
P.D overshoots because K+ ion channels are slow to close
too many potassium ions diffuse out
at less than - 70 mV

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what is the final step of generation and transmission of signals

A

resting potential
original P.D is restored
non-excited state

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

change in light intensity: sensory receptor? energy change?

A

rods and cones in retina

light –> electrical

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

change in temp: sensory receptor? energy change?

A

temp receptors in skin and hypothalamus

heat–> electrical

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

change in the pressure of skin: sensory receptor? energy change?

A

pacinian corpuscles in skin

heat—> electrical

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

change in sound: sensory receptor? energy change?

A

vibration receptors in cochlea of ear

movement—> electrical

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

movement: sensory receptor? energy change?

A

hair cells in inner ear

movement —>electrical

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

change in muscle length: sensory receptor? energy change?

A

muscle spindles in skeletal muscles

movement —> electrical

18
Q

chemicals in air: sensory receptor? energy change?

A

olfactory cells in epithelium lining nose

receptors that detect a chemical and prod. an electrical response

19
Q

chemicals in food: sensory receptor? energy change?

A

chemical receptors in taste buds on tongue

receptors that detect a chemical and prod. an electrical response

20
Q

how does the pacinian corpuscle work

A

pressure deforms the membrane
sodium ion channels open
sodium ions diffuse into neuron
depolarisation creates generator potential
if there’s enough sodium ions it reaches threshold potential

21
Q

what is the node of Ranvier?

A

gap in the myelin sheath where the axon is exposed

22
Q

what is a schwann cell

A

a cell wrapped around the axon forming the myelin sheath

23
Q

where is the cell body of the motor/relay/sensory neuron at

A

cns/cns/pns

24
Q

what does the motor neuron connect

A

CNS to effector

25
Q

what does the relay neuron connect

A

sensory to motor

26
Q

what does the sensory neuron connect

A

PNS to relay

27
Q

what is the refractory period

A

the brief period immediately following the response before it recovers the capacity to make a second response

28
Q

what is a synapse

A

junction between two or more neurons

29
Q

what is the synaptic cleft

A

gap between neurons

30
Q

what is the presynaptic bulb

A

axon end of first bulb

31
Q

what is the presynaptic membrane

A

on next neuron has receptors and binds to neurotransmitter

32
Q

describe the transmission across the synapse (6 marks)

A

. action potential arrives at pre-synaptic bulb
. voltage gated Ca 2+ ion channels open
. Ca 2+ ions diffuse in
. Ca 2+ cause vesicles to move to membrane and release ACh by exocytosis
. ACh diffuses across cleft
. binds to receptor on post-synaptic membrane
. Na + channels open and diffuse into post-synaptic neuron
. ACh turns into acetate and choline with enzyme acetylcholinerase
. choline is recycled into ACh

33
Q

what is a cholinergic synapse

A

uses the neurotransmitter acetylcholine.

34
Q

what are the advantages of myelinated neurons

A

transmit action potential quicker so can reach the end of the neuron faster
they can be longer too so carry impulses at longer distances

35
Q

what is summation

A

when several EPSPs are added together

36
Q

what are EPSPs (excitatory neurotransmitters)

A

stimulate the generation of an action potential in a postsynaptic neurone by opening sodium ion channels in the postsynaptic membrane which causes depolarisation if a threshold is reached

37
Q

define temporal summation

A

impulses that arrive one after the other quickly they can be added together to generate an impulse

large amount of acetylcholine is released into the synaptic cleft

a large number of the gated ion channels open

So a sufficient number of sodium ions pass through the membrane

38
Q

define spatial summation

A

where impulses arrive from different synaptic knobs simultaneously at the same knob this can generate an action potential

large amount of acetylcholine is released into the synaptic cleft

a large number of the gated ion channels open

So a sufficient number of sodium ions pass through the membrane

39
Q

what are IPSPs (inhibitory neurotransmitters)

A

can prevent the generation of an action potential in a postsynaptic neurone

40
Q

what happens if a neurone is subjected to both stimulation form IPSPs and EPSPs? (6 marks)

A

Sodium ions enter the cell body following stimulation by the excitatory synapse

The stimulation of the inhibitory synapse causes potassium ions to diffuse out of the cell body

This cancels out the effect of the sodium ions entering

The threshold potential is not reached so no action potential is generated

41
Q

role of acetylcholinesterase

A

enzyme
hydrolyses acetylcholine into ethanoic acid
and choline
stops transmission of signals

42
Q

why do impulses travel in one direction

A

neurotransmitter is released on one side and its receptors are on the other
chemical transmission cannot occur in the opposite direction
prevents impulses from travelling the wrong way, back to where they were initiated

Biology Module 5 (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions