co-ordination and response

Question 1

what happens in vasoconstriction?

Answer 1

• muscle cells in the walls of the arterioles contract
• causes constriction of blood vessels
• less blood flows through capillaries in the skin
• less heat can be lost by radiation
• skin appears pale

Question 2

what happens in vasodilation?

Answer 2

• muscle cells in the walls of the arterioles relax
• causes dilation of blood vessels
• more blood flows through capillaries in the skin
• more heat can be lost by radiation
• skin appears red

Question 3

what do reflex arcs do?

Answer 3

• control reflex reactions
• make fast, automatic responses
• stop serious damage

Question 4

what does homeostasis allow animals to do?

Answer 4

control the internal environment of their bodies

Question 5

what does homeostasis do?

Answer 5

keeps conditions constant

Question 6

what is controlled in homeostasis

Answer 6

• water content

- body temperature

Question 7

where is adrenaline made and what are the effects?

Answer 7

• made in the adrenal glands

- makes the heart beat faster

Question 8

where is insulin made and what are the effects?

Answer 8

• made in the pancreas

- causes liver + muscles to take up glucose (to keep blood glucose levels normal)

Question 9

where is testosterone made and what are the effects?

Answer 9

• made in the testes

- controls development of male sex organs

Question 10

where is progesterone made and what are the effects?

Answer 10

• made in the ovaries

- maintains the lining of the uterus

Question 11

where is oestrogen made and what are the effects?

Answer 11

• made in the ovaries

- controls development of female sex organs and causes uterus lining to get thick and spongy

Question 12

what is thermoregulation?

Answer 12

the ability to control body temperature

Question 13

what is our average body temperature?

Answer 13

37ºc

Question 14

what are the positive of maintaining are body temperature ?

Answer 14

it allows humans to be active in a range of external activities

Question 15

how do we conserve heat in the cold?

Answer 15

wear more clothes

Question 16

how do we adapt in the heat?

Answer 16

drink lots of water

Question 17

what is the CNS made of?

Answer 17

the brain and spinal cord

Question 18

what do nerves do in the CNS?

Answer 18

branch out of the brain and spinal cord to reach all parts of the body

Question 19

what does the nervous system have?

Answer 19

• fast responses
• short lasting
• nerve cells involved
• electrical impulses that go along nerves

Question 20

what does the hormonal system have?

Answer 20

• slow responses
• long lasting
• glandular cells involved (make hormones)
• hormones transported in the blood

Question 21

what are some sense organs in the nervous system?

Answer 21

• eyes
• nose
• ears
• tongue
• skin

Question 22

what does a co-ordinated response require?

Answer 22

• a stimulus
• a receptor
• an effector

Question 23

what is an example of a response?

Answer 23

sweating

Question 24

what do cone cells in the retina do?

Answer 24

detect colour

Question 25

what do rod cells in the retina do?

Answer 25

detect low levels of light

Question 26

what does the cornea do?

Answer 26

refract light so it passes through the pupil

Question 27

what does the lens do?

Answer 27

focuses light on the retina

Question 28

what does changing shape allow the lens to do?

Answer 28

focus on any objects

Question 29

what happens in the eye to focus on close objects?

Answer 29

- ciliary muscle contracts - suspensory ligaments go loose - lens becomes round in shape

Question 30

what happens in the eye to focus on distant objects?

Answer 30

- ciliary muscle relaxes - suspensory ligaments go tight - lens is stretched to become thinner