Chapter 10

Question 1

what is homeostasis?

Answer 1

the regulation of internal conditions for cells in response to internal and external changes to maintain the best functioning environment

Question 2

why are enzymes so important?

Answer 2

they control the functioning of the cell

Question 3

examples of the internal conditions controlled by homeostasis (3)

Answer 3

blood glucose levels
temperature
water content of the body

Question 4

examples of internal changes (3)

Answer 4

when you get hotter after exercise
when your blood glucose level goes up after eating
when you lose water in hot weather

Question 5

what are receptors?

Answer 5

cells that detect changes in internal or external environment

Question 6

what are coordination centres and what do they do?

Answer 6

areas that receive and process information from the receptors. they send out signals to other parts of the body to react

Question 7

what is an effector?

Answer 7

something that reacts to the changes to restore optimum conditions

Question 8

what does the nervous system do?

Answer 8

sends electrical impulses around the body so you can react to your surroundings

Question 9

how are electrical signals transported?

Answer 9

neurones

Question 10

pathway that an impulse takes

Answer 10

receptor
sensory neurone
relay neurone
motor neurone 
effector

Question 11

difference between neurone and nerve

Answer 11

a nerve is a group of neurones

Question 12

what is the CNS and what does it involve?

Answer 12

the central nervous system, made of brain and spinal cord

Question 13

what is a reflex?

Answer 13

an automatic response

Question 14

examples of a reflex (2)

Answer 14

touching something hot and moving away

something coming at your face and moving

Question 15

why are reflexes so important?

Answer 15

help keep us safe, they happen so fast

Question 16

what are the three neurones involved in a reflex arc?

Answer 16

sensory neurone
motor neurone
relay neurone

Question 17

what do sensory neurones do?

Answer 17

carry impulses from organs to CNS

Question 18

what do relay neurones do

Answer 18

connect sensory neurone and motor neurone, found in CNS

Question 19

what do motor neurones do

Answer 19

carry information from CNS to body

Question 20

describe a reflex arc

Answer 20

the impulse travels from receptor to sensory neurone to relay neurone in CNS to motor neurone and back to effector

Question 21

what is important to remember about reflex arc?

Answer 21

doesn’t need brain’s input

Question 22

what is a synapse?

Answer 22

something connecting the neurones which the impulse must travel across

Question 23

what happens at the synapse?

Answer 23

the electrical impulse can’t cross so releases a chemical that can and this starts a new electrical impulse at the next neurone

Question 24

why is it important reflexes don’t go to conscious area of brain?

Answer 24

would take too long to process

Question 25

what does the cerebral cortex do?

Answer 25

consciousness, intelligence, memory and language

Question 26

what does the cerebellum do?

Answer 26

muscle activity and balance

Question 27

what does the medulla do

Answer 27

unconscious activities like breathing, heart rate and gut movement

Question 28

what does the hypothalamus do?

Answer 28

regulates temperature

Question 29

what does the pituitary gland do?

Answer 29

secretes hormones for other purposes

Question 30

how can scientists find out about the brain? (3)

Answer 30

studying people with brain damage electrical stimulation MRI scans

Question 31

how does studying people with brain damage help scientists learn about the brain?

Answer 31

they can match changes in behaviour with affected areas of the brain

Question 32

what is the importance of the brain?

Answer 32

controls everything processes information sends out necessary signals for response

Question 33

how can electrically stimulating the brain help scientists?

Answer 33

they can see what effect stimulating different areas has

Question 34

how can MRI scans help scientists?

Answer 34

it shows what area of the brain is effected by a certain problem, e.g. a tumour so they can see what effect this has on the body, for example if a person can't walk

Question 35

problems with the brain

Answer 35

very easily damaged and destroyed easy to cause unintended damage in surgery difficult to treat conditions, can't reach with drugs

Question 36

function of sclera

Answer 36

tough so eye is not easily damaged

Question 37

function of cornea

Answer 37

lets light into eye

Question 38

function of iris

Answer 38

controls size of pupil

Question 39

function of suspensory ligaments and ciliary

Answer 39

changes shape of lens

Question 40

function of lens

Answer 40

focusses light rays on retina

Question 41

function of retina

Answer 41

sends impulses to brain along optic nerve

Question 42

how is light focusses on retina?

Answer 42

refraction

Question 43

what is accommodation?

Answer 43

changing the shape of the lens so you can see clearly

Question 44

what are the light rays form a near object like?

Answer 44

very spread out

Question 45

what are the light rays from a distant object like?

Answer 45

flat, almost parallel

Question 46

how does your eye change to see distant objects?

Answer 46

ciliary muscles relax suspensory ligaments puled tight lens flat and thin small refraction

Question 47

how does you eye change to see near objects?

Answer 47

ciliary muscles pulled tight suspensory ligaments relax lens fat and thick large refraction

Question 48

what is myopia?

Answer 48

short sightedness

Question 49

what is hyperopia?

Answer 49

long sightedness

Question 50

what is short sightedness?

Answer 50

when near objects are clear but distant ones are blurry

Question 51

what is hyperopia?

Answer 51

distant objects are clear but near ones are blurry

Question 52

why does myopia happen?

Answer 52

the light rays are focusses infant of the retina so the image there is blurry

Question 53

how to correct myopia

Answer 53

concave lens; spreads out light rays so lens can focus them correctly onto retina

Question 54

why does hyperopia happen?

Answer 54

light is focussed behind retina?

Question 55

how to correct hyperopia

Answer 55

convex lens; brings light rays closer together so lens perfectly focuses on retina

Question 56

how is laser eye surgery used to correct myopia?

Answer 56

makes lens thinner so refraction is weaker

Question 57

how can laser eye surgery correct hyperopia?

Answer 57

changes shape of lens so refraction is stronger

Question 58

what is ADH and what does it do?

Answer 58

hormone | released from brain to tell kidneys how much water to retain

Question 59

where is ADH released from

Answer 59

pituitary gland

Question 60

where is insulin produed?

Answer 60

pancreas

Question 61

where is insulin stored?

Answer 61

liver

Question 62

what part of the eye controls how much light gets through?

Answer 62

iris

Question 63

what are the chemicals used to cross the synapse?

Answer 63

neurotransmitters

Question 64

what happens when adrenaline is released?

Answer 64

stimulates (increased glucose, increased heart rate, increased breathing rate) for increased respiration for more energy to run