Nervous System

Question 1

Functions and part of motor neuron

Answer 1

dendrites-receive signals to deliver to cell body
cellbody- site of neuron metabolism
axon- carries signals away from dendrites
node of ranvier-allows impulse to jump from node to node

Question 2

sensory neuron vs motor neuron

Answer 2

sensory sends signal from pns to cns, motor cns to pns

Question 3

name all types of neurons

Answer 3

association (interneuron), motor, and sensory

Question 4

Membrane potential

Answer 4

High Na low K on outside, High K low Na inside

Question 5

how is membrane potential achieved

Answer 5

Active transport of sodium through NaK pump. For every 2 K pumped in, 3 Na is pumped out.

Question 6

homeostasis

Answer 6

where constant internal environment is maintained despite changes in external environment

Question 7

5 properties common to all control systems

Answer 7

limit, energy requirement, error, feedback, overshoots

Question 8

factors that influence intensity of a sensation

Answer 8

amount of neurons stimulated, size of axons- diameter, if larger will travel faster, frequency of stimulus

Question 9

refractory period

Answer 9

recovery time required before a neuron allows another action potential to occur (occurs during depolarization)

Question 10

Glial cells

Answer 10

cells that support the neurons, outnumber neurons

Question 11

types of neurons and functions

Answer 11

sensory- transmit impulses from sensory receptors to the interneurons.
interneurons- found in the brain and spinal cord. Act as link between sensory and motor neurons.
motor neurons- conduct impulses from interneurons to effectors(muscle)

Question 12

difference between white and grey matter

Answer 12

myelinated neurons form white matter while unmyelinated form grey ‘H’

Question 13

where does action potential occur

Answer 13

in node of ranvier of myelinated neurons

Question 14

when does the sodium gate open

Answer 14

during depolarization (flows in)

Question 15

when does the potassium gate open

Answer 15

during repolarization (flows out)

Question 16

Saltatory conduction

Answer 16

conduction of a impulse along a myelinated neuron

Question 17

neuromuscular junction

Answer 17

synapse between motor neuron and muscle cell

Question 18

name a neurotransmitter that crosses a neuromuscular junction

Answer 18

acetylcholine

Question 19

what breaks down acetylcholine

Answer 19

cholinesterase

Question 20

meninges

Answer 20

prevent direct circulation of blood through the cells of the brain and spinal cord (blood brain barrier)- dura mater, arachnoid layer, pia mater.

Question 21

the somatic system includes how many cranial nerves and spinal nerves

Answer 21

12 pairs of myelinated cranial and 31 pairs of spinal nerves.

Question 22

4 types of receptors

Answer 22

photoreceptors- light
chemoreceptors- chemical, odour , taste
mechanoreceptor- pressure, hearing
thermoreceptor- heat and cold

Question 23

what is accommodation

Answer 23

ability of lens to change shape

Question 24

astigmatism

Answer 24

uneven curving of the cornea causing blurred vision

Question 25

myopia

Answer 25

nearsightedness. Long eye ball causes image to fall in front of the retina. Need concave lens.

Question 26

hyperopia

Answer 26

farsightedness. Short eye ball causes image to fall behind retina. Need convex lens

Question 27

names of ossicles

Answer 27

malleus (hammer), incus (anvil), stapes (stirrup)

Question 28

what structures involve balance

Answer 28

semicircular canals, utricle, saccule.

Question 29

proprioceptors

Answer 29

from muscles, joints, and tendons inform the brain of the position of body parts