B13 coordination and response

Question 1

how do electrical impulses travel

Answer 1

neurones

Question 2

describe the mammalian nervous system

Answer 2

central nervous system (CNS)
- brain
- spinal cord
peripheral nervous system (PNS)
- nerves outside brain and spinal cord

Question 3

describe the role of the nervous system

Answer 3

coordination and regulation of body function

Question 4

what is this

Answer 4

sensory neurone

Question 5

what is this

Answer 5

relay neurone

Question 6

what is this

Answer 6

motor neurone

Question 7

describe a simple reflex arc

Answer 7

1. receptor detects stimuli
2. sensory neurone sends nerve impulses to relay neurone in spinal cord
3. spinal cord coordinates response by sending nerve impulses from relay neurone to appropriate motor neurones
4. send nerve impulses to effector to carry out response

Question 8

describe what is meant by a reflex action

Answer 8

• means of automatically and rapidly
• integrating and coordinating stimuli
• with the responses of effectors (muscles and glands)

Question 9

describe what is meant by sense organs

Answer 9

groups of receptor cells responding to specific stimuli
- light
- sound
- touch
- temperature
- chemicals

Question 10

define hormone

Answer 10

• chemical substance
• produced by a gland
• carried by the blood
• alters the activity of one or more specific target organs

Question 11

what hormone do the adrenal glands secrete

Answer 11

adrenaline

Question 12

what hormone does the pancreas secrete

Answer 12

• insulin
• glucagon

Question 13

what hormone do the testes secrete

Answer 13

testosterone

Question 14

what hormone do the ovaries secrete

Answer 14

oestrogen

Question 15

describe adrenaline

Answer 15

• hormone secreted in “fight or flight” situations
• increases breathing rate
• increases heart rate
• increases pupil diameter

Question 16

where are the adrenal glands

Answer 16

on top of the kidneys

Question 17

define homeostasis

Answer 17

the maintenance of a constant internal environment

Question 18

explain the concept of homeostatic ocntrol

Answer 18

• controlled by negative feedback
• change to conditions in system causes response that reverses change
• return to normal levels, set point

Question 19

what happens when blood glucose concentration is too high

Answer 19

• insulin secreted
• stimulates cells in liver and tissues to take in glucose from blood
• for respiration or convert to glycogen for storage

Question 20

what happens when blood glucose concentration is too low

Answer 20

• glucagon secreted
• stimulates liver cells to convert stored glycogen into glucose

Question 21

what happens when internal body temperature falls

Answer 21

• hypothalamus coordinates changes needed to control body temperature (receptors constantly measure temp of blood, receive info from temp receptors in skin)
• shivering
• vasoconstriction of arterioles supplying skin surface capillaries

Question 22

what happens when internal body temperature rises

Answer 22

• hypothalamus coordinates changes needed to control body temperature (receptors constantly measure temp of blood, receive info from temp receptors in skin)
• sweating
• vasodilation of arterioles supplying skin surface capillaries

Question 23

Answer 23