Nervous system

Question 1

what is the difference between signalling between vs wishin neurons

Answer 1

within = electrical
between = chemical

Question 2

the nervous system is divided into two, what are they

Answer 2

• central nervous system
• peripheral nervous system

Question 3

what does the CNS do?

Answer 3

coordinates activities of all parts of the body

Question 4

what does the PNS do?

Answer 4

connects to the CNS to enable the animal to respond to stimuli

Question 5

What is the CNS composed of?

Answer 5

brain, spinal cord
- contains relay neurons

Question 6

what is the PNS composed of?

Answer 6

Cranial nerves, spinal nerves, peripheral nerves
- contains sensory + motor neurons

Question 7

what are the two types of autonomic nervous systems

Answer 7

parasympathetic division
sympathetic division

Question 8

Parasympathetic division

Answer 8

body functions during rest

Question 9

Sympathetic division

Answer 9

during activity or stress

Question 10

what are ganglia

Answer 10

clusters of nerve cell bodies found throughout the body

Question 11

what are the three major sections of the brain

Answer 11

Hindbrain, Midbrain, Frontbrain

Question 12

function of the spinal cord

Answer 12

contains nerve tracts signals to and from the brain
- acts as the site for simple reflexes

Question 13

main functions of the PNS in vertebrates

Answer 13

• connects CNS to organs
• carries info to and from CNS
• allows brain and spinal cord to receive and send into to other areas of the body
• regulates involuntary body functions (breathings)

Question 14

Sensory-somatic nervous sytem

Answer 14

regulates activities under voluntary control
e.g. muscle movement

Question 15

Visceral/ Autonomic nervous system

Answer 15

monitors internal environment and controls organ function (involuntary)

Question 16

what are the three types of ion channels in neurons

Answer 16

voltage activated Na+
voltage activated K+
voltage gated Ca2+

Question 17

4 stages of changes in the membrane potential (mechanisms)

Answer 17

Threshold, Upstroke, Overshoot, Afterpotential/Hyperpolarizatio

Question 18

what happens in the threshold stage

Answer 18

depolarisation of the membrane
- eg inflow of sodium = inside becomes more positive

Question 18

what happens in the upstroke stage

Answer 18

more positive and reaches a peak

Question 19

what happens in the overshoot stage

Answer 19

shoot over the zero line (from peak to zero)

Question 20

what happens in the after potential or hyperpolarization stage

Answer 20

sodium channels blocked or potassium pushed out of cells or inflow of chloride
(inside of the cells become negative again)

Question 21

what is myelin used for relating to the cell membrane

Answer 21

reduces the membrane area, resulting in less contact with external environments
- pumps will have to do less work

Question 22

what are the two types of synapses

Answer 22

chemical
electrical