Biology- Homeostasis And Response

Front 1

what is homeostasis?

Back 1

homeostasis is how the body creates and controls a stable internal e

Front 2

describe negative feedback

Back 2

receptors detect a change in levels(stimulus)

the coordination center organises a response

an effector produces a responce to counteract the change in level/

Front 3

What does the nervous System do?

Back 3

detect stimuli

Front 4

what is the CNS

Back 4

the CNS consists of the brain and spinal chord. It is connected to the body by sensory neurones

Front 5

what are sensory neurones

Back 5

they carry information from receptors to the CNS

Front 6

what are motor neurons?

Back 6

neurones that carry impulses from theCNS to effectors

Front 7

describe a reflex arc

Back 7

sensory neuron>relay neuron>motor neuron>effector

Front 8

Lable

Back 8

1)medulla

2)spinal chord

3)cerebellum

4)cerebral cortex

Front 9

give 3 methods of studying the brain

Back 9

1)using brain damaged people

2)electrically stimulating parts of brain-observing

3)MRI scans form a picture

Front 10

lable

Back 10

1)suspensory ligaments

2)don't need to know

3)Iris

4)pupil

5)cornea

6)cilliary muscle

7)Lens

8)Retina

9)dont need to know

10)Optic nerve

Front 11

how does your eye look at near objects?

Back 11

muscles tighten,ligaments relax

Front 12

how can you counteract hyperopia

Back 12

farsightedness can be fixed with a convex lens

Front 13

how can you counteract myopia

Back 13

short sightedness can be fixed with a concave lens

Front 14

give two surgical ways to fix eye problembs

Back 14

laser eye surgery changes cornea shape

replacement lens surgey gives you an artificial lens

Front 15

what acts a as a coordination center for change in temperature

Back 15

thermoregulatory center

Front 16

how does you body keep cool/cool down

Back 16

hairs lie flat

sweating

blood vessels near skin dilate to allow heat to escape

Front 17

how do you heat up/stay hot

Back 17

hairs stand up

stop sweating

blood vessels near skin constict

shivering

Front 18

what are hormones

Back 18

chemical messages sent in bloodstream

Front 19

name 6 endocrine glands and their purpose

Back 19

Pituitary-regulate body conditions

ovaries-oestrogen

Testes-testosterone

Thyroid-thyroid

Adrenal-adrenaline

pancreas-insulin

Front 20

how does you body lower blood sugar levels?

Back 20

by producing insulin to turn glucose into glycogen which is absorbed mainly ito the liver

Front 21

how does your body raise blood-sugar levels?

Back 21

by producing glucagon which turns glycogen into glucose which goes back into bloodstream

Front 22

what is the difference between type 1 and type 2 diabetes?

Back 22

1)pancreas produces little or no insulin

2)cells don't respond properly to insulin

Front 23

what do kidneys do?

Back 23

they filter the blood

Front 24

what is urea?

Back 24

because protein cant be stored it is coverted to fats and carbohydrates. it also produces ammonia which is toxic so it's converted to urea,which is then filtered out of the blood by the kidneysand into the urine

Front 25

what else does the kidney filter out?

Back 25

Ions(from food) have to be kept in balance with water, too much or little will upset osmosis. so some ions are lost in sweat but the rest is maintained by the kidneys.-ions>reabsorbed/+ions lost in urine

water going out has to balance going in and we dont lose enough from sweat so the kidneys get rid of it in urine

Front 26

describe the 4 stages of the menstrual cycle

Back 26

1)1-menstruation starts(uterus lining breaks down for 4 days)

2)4-14 uterus lining builds up again

3)14-developed egg released(ovulation)

4)14-28-wall maintained. If no fertilised egg lands on by by 28 it begins again.

Front 27

where is FSH made and what does it do?

Back 27

pituritary gland, causes egg to mature in a follicile in an ovarie and stimulates oestrogen

Front 28

where is oestrogen made and what does it do?

Back 28

ovaries, causes uterus lining to grow and stimulates LH. an inhibits FSH

Front 29

where is LH produced and what does it do?

Back 29

pituitary gland. stimulates ovulation

Front 30

where is progestrone made and what does it do?

Back 30

made by remains of follicle in ovarie. maintains uterus lining and inhibits production of FSH and LH

Front 31

how can hormones be used to reduce fertility

Back 31

if enough is taken it inhibits production of FSH. It also produces a thick mucus that prevents sperm from reaching egg. side effects

Front 32

how can hormones be used to increase fertility?

Back 32

some women have low FSH levels so they can be given to them as drugs along with LH to stimulate ovulation. side effects

Front 33

How does IVF work

Back 33

eggs collected from ovaries are fertilised(ICSI may be used which injects sperm into egg) in lab. they are grown into embryos in an incubator. once they are more developed they are put into the uterus to grow.

Front 34

what does adrenaline do?

Back 34

increases supply of O2 and glucose to brain and muscles.

Front 35

how does negative feedback regulate thyroxine

Back 35

thyroxine controls basal metabolic rate and is regulated by TSH. when thyroxine levels are too high TSH is inhibited so thyroxine falls to normal.