Homeostasis

Question 1

what is homeostasis

Answer 1

maintaining a constant internal environment

Question 2

what and where is the hypothalamus

Answer 2

in the brain and it detects body temperature

Question 3

what is the stimuli

Answer 3

a change in the environment

Question 4

what is a receptor

Answer 4

cells that detect stimuli

Question 5

describe homeostasis

Answer 5

1. receptors detect changes in the body
2. the control centre send out signals to coordinate a response
3. effecter (can be a muscle or gland) bring about the response

Question 6

How does the nervous system work

Answer 6

receptor, sensory neurone, CNS, motor neurone, effecter, response

Question 7

The full reflex equation

Answer 7

1. stimulus - change in the environment
2. receptors on the skin will detect the stimulus
3. an electrical impulse travels along the sensory neurone to the CNS
4. after the sensory neurone there is a synapse where chemicals diffuse
5. the electrical impulse continues to the relay neurone until it reaches another synapse and then continues along the motor neurone
6. and finally reaches the effector (can be a muscle or gland)

Question 8

what are the ciliary muscles and the suspensory ligaments

Answer 8

they change the shape of the lens to focus light on the retina

Question 9

in bright light what happens to the eye muscles

Answer 9

• circular muscles contract
• radial muscles relax
• pupil constricts

Question 10

in dim light what happens to the eye muscles

Answer 10

• circular muscles relax
• radial muscles contract
• pupil dilates

Question 11

what is the Cerebral cortex

Answer 11

memory, consciousness, language and intelligence

Question 12

what is the Cerebullum

Answer 12

coordination of all muscular activity

Question 13

what is the medulla

Answer 13

Unconsciousness Activity - heart beat and breathing

Question 14

give me some example of homeostasis

Answer 14

blood glucose concentration 
body temperature 
water content of the body 
blood pressure 
salt iron concentration

Question 15

what is the S,R,M in storm

Answer 15

sensory, relay, motor neurone

Question 16

how does the eye focus on an image

Answer 16

the cornea bends (or refracts) light

the lens produces further refraction

an image is bought into focus on the retina

optic nerve carries nerve impulses to the brain

Question 17

what is the cornea

Answer 17

the transparent region of the sclera at the front of the eye, it refracts light

Question 18

what is the iris

Answer 18

it has sets of muscles that control the size of the pupil and regulates the light reaching the retina

Question 19

what is the retina

Answer 19

made up of light sensitive cells called receptor cells (cone and rod cells)

Question 20

what is the sclera

Answer 20

tough outer white layer of the eye that protects and hold the eye in place

Question 21

what is the optic nerve

Answer 21

nerve that carries impulses from the retina to the brain

Question 22

what is myopia

Answer 22

short sightedness when people see objects close but cant distant objects

Question 23

when does myopia happen

Answer 23

the eyeball is to long
cornea is too curved
light focusses in front of the retina

Question 24

how can myopia be fixed

Answer 24

concave lens

Question 25

what is hyperopia

Answer 25

long sightedness when people see objects at long but struggle to see near

Question 26

why does hyperopia happen

Answer 26

light focusses behind the retina eyeball is too short cornea not curved enough

Question 27

how can hyperopia be fixed

Answer 27

convex lens

Question 28

vasodilation?

Answer 28

blood cells widen blood vessels can rise closer to your skin so that heat energy can be released into the environment

Question 29

vasoconstriction?

Answer 29

when your cold blood vessels get smaller so they are not close to your skin to stop heat energy from being released

Question 30

why is it important to be able to control your internal environment

Answer 30

cells need the right conditions to function properly right conditions for enzyme activity

Question 31

why does homeostasis need to maintain optimal conditions

Answer 31

cells depend on the bodies environment to live and function

Question 32

list three conditions that the body needs to maintain

Answer 32

water content blood glucose body temperature

Question 33

what is a sensory neurone

Answer 33

the sensory neurones carry information as electrical impulses from the receptors to the CNS

Question 34

what is a motor neurone

Answer 34

the neurones that carry electrical impulses from the CNS to effectors

Question 35

what is an MRI

Answer 35

a scan which uses strong magnetic fields and radio waves to produce detailed images of the inside of the body

Question 36

what is an EEG

Answer 36

recording of brain activity

Question 37

Far Objects

Answer 37

ciliary muscles relax so lens is flatter and thinner suspensory ligaments tighten allows light to focus on retina

Question 38

close objects

Answer 38

ciliary muscles contract so lens becomes fatter and wider suspensory ligaments loosen this allows light to focus on the retina