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Flashcards in Neorotransmitters Deck (21):
1

What is a neuron

Cells that make up nervous system

Adapted to carry impulses

2

What do neurona contain ? And what do they do?

Dendrites and axons

Dendrites carry impulses to cell body
Axons carry away from cell body

3

What are the three types of neurons

Sensory
Inter
Motor

4

What is a Myelin sheath and what does it do?

Are around longest fibres
Made up of cells and contain fatty material
Insulate the fibre which speeds up nervous impulses

5

What are the roles of glial cells

Provide physical support for neurons

Production of Myelin sheath

Maintain homeostatic environment around neurons

Remove debris from area by phagocytosis

6

What do sensory neurons do?

Carry impulses from dense organs to CNS

7

What do inter neurons do?

Connect other neurons to CNS

8

What do motor neurons do

Carry impulses from CNS to muscles or glands

9

Steps of synapses

1. Nervous impulses travel down pre-synaptic Axon
2. Vesicles with neurotransmitter moves to and fuse w. Pre-synaptic membrane
3. Neurotransmitter secreted into synaptic cleft
4. Receptors in post-synaptic membrane recognise transmitter molecules
5. Nervous impulses continue along dendrite if post synaptic neuron

10

What is a converging neural pathway?

Stimuli from several neurons converge on one neuron
For example retina of eye - dim lights insufficient to pass on impulse

11

What is a diverging neural pathway

Impulse from single neuron can be passed on to several more
More than one muscle to move at a time

12

What is a reverberating pathway

Impulses can be recycled back through oaychsay to bring about repeated activities like breathing

13

What is placricity of response

Creation of new neural pathways

14

Why might a new neural pathway be made

Learn new skill
Recovery from brain damage
Reflex action

15

What is endorphins and when are they released

Release from neurons involved in pathways related to reduction of pain, euphoric feeling, sex, and appetite
They increase when sever injury, prolonged exercise, stress and eating certain foods

16

Agonistic drugs

Mimic neurotransmitter and enhance action

Fit in receptors

17

Antagonist

Block action of neurons to prevent impulses

18

Inhibitor drugs

Some may inhibit action of enzymes to remove neurotransmitters
Others inhibit reabsorbtion of them

19

Recreational drugs

Affect reward circuit of brain
Alter mood , perception and consciousness

Cannabis and cocaine

20

Drug addiction

Sensitisation

Increased sensitivity and Number of receptors
Lead to addiction

21

Drug addiction

Desensitisation

Decrease in sensitivity and number of receptors

Drug tolerance