Nervous system

Question 1

Components of the CNS?

Answer 1

Brain and spinal cord

Question 2

2 parts of the PNS?

Answer 2

Afferent nerves (sensory)
Efferent nerves (motor)

Question 3

characteristics of a neuron?

Answer 3

• highly specialised
• surrounded by myelin sheath
• used for communication

Question 4

what produces myelin?

Answer 4

PNS - schwann cells
CNS - oligodendrocytes

Question 5

components of a neuron and their functions

Answer 5

Body (soma) = control centre, nucleus
Dendrite = branch that receives impulses
Axons = axonal hillock, transmits signals

Question 6

what are nerves?

Answer 6

• bundle of fibres

Question 7

What is the resting potential of a neuron?

Answer 7

-70mV

Question 8

Which way do action potentials travel?

Answer 8

From dendrites to axons

Question 9

What are nerve impulses?

Answer 9

A change in membrane potential which allows signalling or excitation

Question 10

What is a synapse?

Answer 10

Where one neurone meets another

Question 11

What is a neurotransmitter?

Answer 11

Chemical signal triggered by an action potential

Question 12

How does depolarisation of nerves occur?

Answer 12

Impulse reaches pre-synapse and binds to post-synaptic receptors

Question 13

What is summation?

Answer 13

Combination/sum of all graded potentials in the post-synaptic neuron

Question 14

what do nerves do?

Answer 14

• sends impulses from CNS to body

Question 15

what is the epineurium?

Answer 15

layer that covers each nerve by connective tissue

Question 16

what is the perineurium?

Answer 16

complete sleeve around the axon bundle

Question 17

what is the endoneurium?

Answer 17

covers each fibre, fluid

Question 18

what is the fascicle (PNS) and tract (CNS)?

Answer 18

small bundle of axons

Question 19

2 divisions of the peripheral nervous system?

Answer 19

somatic and autonomic

Question 20

2 parts of the autonomic system?

Answer 20

sympathetic and parasympathetic

Question 21

what are astrocytes?

Answer 21

physical barrier that support neurones

Question 22

what do astrocytes do?

Answer 22

enable homeostasis and reuptake of neurotransmitters

Question 23

what are microglia?

Answer 23

immune cells of the brain

Question 24

3 types of functional neurones?

Answer 24

afferent (sensory)
efferent (motor)
interneurons

Question 25

what do afferent neurones do?

Answer 25

send signals from periphery to CNS (Sense)

Question 26

what do efferent neurones do?

Answer 26

send signals from CNS to muscles/skin (respond)

Question 27

what do interneurons do?

Answer 27

connect brain and spinal cord in CNS

Question 28

what do nerves do?

Answer 28

conduct impulses between brain/spinal cord and body

Question 29

what does an action potential change the membrane potential to?

Answer 29

+30mV

Question 30

how are electrical impulses formed?

Answer 30

by ions moving into the neuron

Question 31

what does dendritic depolarisation do?

Answer 31

opens voltage gated sodium channels

Question 32

why can an action potential only move one way?

Answer 32

change in membrane potential causes more Na+ channels to open channels behind the Ap become inactive

Question 33

what is the grey matter of the brain?

Answer 33

cortex containing nerve cell bodies

Question 34

what is the white matter of the brain?

Answer 34

axons

Question 35

what does the brain stem control?

Answer 35

involuntary functions, blood pressure, breathing

Question 36

what does the cerebellum do?

Answer 36

co-ordinates balance and movement

Question 37

what does the diencephalon control?

Answer 37

homeostasis

Question 38

what is the basal ganglia for?

Answer 38

motor control

Question 39

2 parts of limbic system?

Answer 39

amygdala - emotion and memory hippocampus - learning and memory

Question 40

3 parts of the cerebrum?

Answer 40

basal ganglia limbic system pituitary gland

Question 41

where do sensory nerves enter spinal cord?

Answer 41

dorsal root

Question 42

where do motor nerves enter spinal cord?

Answer 42

enteral root

Question 43

what are peripheral nerves?

Answer 43

nerves that branch off from spinal cord

Question 44

what do visceral sensory neurons monitor?

Answer 44

pain, temp, irritation

Question 45

what is visceral reflex?

Answer 45

reflex arc of autonomic nervous system

Question 46

effector neurotransmitter of sympathetic system?

Answer 46

noradrenaline (norepinephrine)

Question 47

effector neurotransmitter of parasympathetic system?

Answer 47

acetylcholine

Question 48

what class are the postganglionic nerves in the sympathetic system?

Answer 48

adrenergic