Chapter 13 - Nueronal Communication Flashcards Preview

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Flashcards in Chapter 13 - Nueronal Communication Deck (35):
1

What is the definition of homeostasis

The maintenance of a constant internal environment

2

What are the three types of nuerone

Relay

Motor

Sensory

3

What is the definition of a nuerone

Specialised cells that rapidly transmit electrical impulse

4

Describe structure of motor nuerone

1 long axon and many short dendrite with nucleus at one end

5

Structure of sensory neurone

1 axon and 1 dendron with nucleus in middle of cell body

6

In which direction does an axon carry an electrical impulse

Away from cell body

7

What is the structure of relay neurone

Many short axons and dendrite

8

What does a sensory cell send impulse on to

Relay or motor neurones

Brain

9

Where does motor neuron recieve impulse from

Either relay or sensory neurones

10

Where does motor neurone send impulse to

Effector

11

Where does a relay neurone receive and send impulses to

Between all neurones

12

Where does sensory neurone send impulse to

Relay

Motor

Brain

13

What are key features to neurone

Mitochondira and endoplasmic reticulum

Enable production of neurotransmitters

14

What is the flow of an electrical impulse?

Receptor

Sensory

Relay

Motor

Effector

15

What is myelin sheath made of

Layers of plasma membrane

16

What produces layers of membrane that make up myelin sheath

Schwann cells

17

What is the role of myelin sheath

To increase rate of transmission

18

What are the gaps in myelin sheath called and what is there purpose?

Nodes of ranvier

To increase rate of transmission by making impulse jump

19

What is potential difference

The difference in charge on 2 sides of membrane

20

When resting what is the state of membrane charge

polarised

21

What is resting potential on inside of nuerone

-70mv

22

For each molecule of ATP hydrolysed how many molecules are pumped

3 NA

2K

23

What is the name of the mechanism used to pump ions in nuerone

Sodium-pottasium pump

24

Is sodium moved in or out of nuerone

Out

25

What is charge on sodium ion

+

26

What is overall charge on outside of cell

Negative

27

To produce an impulse what does charge have to change to

+40mv

28

How is the change in charge achieved in nuerome

Membrane becomes more permeable to NA+

29

How does movement of NA+ cause depolarisation

Na+ is actively pumped out of nuerone

When permeability increases NA+ moves back in the charge increases

30

What are the 5 stages of an action potential

Resting potential

All or nothing principle

Depolarisation

Channel movement

Repolarisation

Hyperpolarisation

31

What has to be reached for action potential to occur

Threshhold value

32

What can effect threshold value

The frequency of impulse as all impulse same size

33

What happens when NA+ change charge to threshold value

Action potential produced

34

When the inside of nuerone is positive what is the term for this state

aDepolarised

35

What happens after threshold value had been reached in terms of channels

Na + channel close
K+ channel open