Nerves

Question 1

Where are the cell bodies of sensory fibres?

Answer 1

Ganglion

Question 2

Where are the cell bodies of motor fibres?

Answer 2

Ventral horn

Question 3

Term when the inside of a cell becomes more negative

Answer 3

Hyperpolarises

Question 4

How does the structure of the blood brain barrier protect the brain?

Answer 4

Astrocytes and tight junction make the endothelial cells “tight” which protects the brain from changed in [K+]

Question 5

Term when the inside of a cell becomes more positive

Answer 5

Depolarises

Question 6

Normal RMP for cells and what is it due to?

Answer 6

-70mV (close to K equilibrium potential)

Other leaky channels (Na+ and Cl-) and Na/K pump

Question 7

Effect of more open K channel

Answer 7

K flow out and hyper-polarises

Question 8

Effect of open Na+ channels

Answer 8

Na+ flow in and depolarises

Question 9

Effect of open Cl- channels

Answer 9

Cl flow in and hyper-polarises

Question 10

Effect of open Ca2+ channels

Answer 10

Ca2+ flow in and depolarises

Question 11

Explain repolarisation

Answer 11

Return to RMP

Question 12

Explain overshooting

Answer 12

Exceeds 0mV

Question 13

Properties of graded potentials

Answer 13

• Electrotonic
• Decremental
• Non-propagated
• Local

Question 14

What are the classifications of nerves fibres?

Answer 14

Afferent, Efferent, interneurones

Question 15

Function of afferent neurones

Answer 15

Sensory nerves that detect stimuli

Question 16

Function of interneurones

Answer 16

Within the spinal cord and relays signals between afferent and efferent nerves

Question 17

Function of efferent neurones

Answer 17

Motor neurones that carry signals to effector tissues or cells