Animal coordination, control and homeostatsis

Question 1

what are hormones

Answer 1

they are chemicals released by the body that affect particular cells

Question 2

what are endocrine glands

Answer 2

they release hormones

Question 3

when is the pituitary gland found

Answer 3

in the brain

Question 4

what is the pituitary gland

Answer 4

this is the main gland and it releases hormones that maintain body conditions. these hormones also act on other glands

Question 5

what hormones does the pituitary gland release

Answer 5

it releases many but the main ones are FSH and LH

Question 6

where are the ovaries found

Answer 6

in the female body near the hip

Question 7

what hormones do ovaries release

Answer 7

oestrogen

Question 8

what is oestrogen involved in

Answer 8

menstrual cycle

Question 9

where are the testes found

Answer 9

in the male body and near the hip

Question 10

what hormones do testes release

Answer 10

testosterone

Question 11

what is the hormone released by the testes responsible for?

Answer 11

it controls puberty and sperm production in males

Question 12

where is the thyroid gland found

Answer 12

in the neck

Question 13

what hormone does the thyroid gland release

Answer 13

thyroxine

Question 14

what does thyroxine do

Answer 14

it regulates rate of metabolism, heart rate and temperature

Question 15

where are the adrenal glands found

Answer 15

in the stomach area

Question 16

what hormones do adrenal glands produce

Answer 16

adrenalin

Question 17

what does adrenaline do

Answer 17

targets vital organs, increases the heart rate and boosts the delivery of oxygen. it gets the brain ready for a fight or flight response

Question 18

where is the pancreas found

Answer 18

in the stomach area

Question 19

what hormones do pancreas produce

Answer 19

insulin and glucagon

Question 20

what are insulin and glucagon used for?

Answer 20

to regulate blood glucose level

Question 21

what are the differences between neurons and hormones

Answer 21

neurons:
-fast action
-act for a short time
-act in a precise area
hormones:
-slower action
-act for a long time
-act in a more general area

Question 22

how does adrenaline make your heart rate and blood pressure increase

Answer 22

it binds onto specific receptors in the heart. this will make the heart contract quicker

Question 23

what is negative feedback

Answer 23

this is how the body controls the level of hormones in the blood. If the body detects that the level of a substance is above or below the normal level, it triggers a response to get it back to normal again

Question 24

how is the amount of thyroxine in blood regulated?

Answer 24

-when thyroxine level is lower than normal, the hypothalamus is stimulated to release TRH
-TRH stimulates the pituitary gland to release TSH
-TSH stimulates the thyroid hormone to release thyroxine, so the blood thyroxine level rises back towards normal

Question 25

what occurs in the four stages of the menstrual cycle

Answer 25

Stage 1- Day 1 is when mensuration starts. in this stage, the lining of the uterus breaks down and is released Stage 2- the uterus lining is repaired. from day 4 to 14, it becomes a thick spongy layer full of blood vessels ready for a fertilized egg to get implanted Stage 3- an egg develops and is released from the ovary at day 14 Stage 4- the lining is maintained until day 28. if no fertilised egg has landed on the uterus, the spongy lining breaks down and starts again

Question 26

what is the purpose of FSH in the menstrual cycle

Answer 26

this causes the follicle to mature. it also stimulates oestrogen production

Question 27

what is meant by the follicle

Answer 27

this is the egg and its surrounding cells

Question 28

what is the purpose of oestrogen in the menstrual cycle

Answer 28

causes the lining of the uterus to thicken and grow. stimulates LH

Question 29

what is the purpose of LH in the menstrual cycle

Answer 29

stimulates ovulation at day 14. it also makes the leftover follicle to develop into corpus luteum which secretes progesterone

Question 30

what is the purpose of progesterone in the menstrual cycle

Answer 30

maintains the lining of the uterus. stops the release of FSH and LH. this stops another egg being released

Question 31

what happens when there is low progesterone and oestrogen level

Answer 31

the uterus lining breaks down

Question 32

what happens when there is low progesterone level

Answer 32

this allows the FSH to increase which will start over the menstrual cycle

Question 33

what happens to the progesterone level if an egg is released

Answer 33

the level progesterone will remain high to maintain the lining of the uterus

Question 34

what is clomifene therapy

Answer 34

this is when women who dont ovulate take a drug called clomifene. this causes more FSH and LH to be released by the body, which stimulates egg maturation and ovulation. the couple can have sex during this period to improve the chance of becoming pregnant

Question 35

what is in vitro fertilisation

Answer 35

this is when eggs from women and sperm from men are taken and grown into embryos in a lab. then, they will be transferred into the womans uterus to improve the chance of pregnancy

Question 36

how can oestrogen act as a contraceptive

Answer 36

if oestrogen is taken every day, it will keep the level of oestrogen high which will then inhibit the production of FSH

Question 37

how can progesterone act as a contraceptive

Answer 37

this stimulates the production of thick mucus. this will prevent the sperm from getting through the entrance of the uterus

Question 38

what happens when blood glucose concentration is too high?

Answer 38

-insulin is secreted by the pancreas. -the glucose then moves from the blood into liver -the insulin then makes the liver turn the glucose into glycogen

Question 39

what happens when blood glucose concentration is too low

Answer 39

-glucagon is secreted by the pancreas -the glucagon then enters into the liver -it makes the liver turn the glycogen stored in the liver into glucose -this glucose is then released into the blood

Question 40

what is type 1 diabetes

Answer 40

this is when the pancreas produces little or no insulin. this will cause the persons blood glucose to rise which can be fatal.

Question 41

how can type 1 diabetes be treated

Answer 41

this is treated with insulin therapy. this involves the person injecting insulin into fatty tissue so it can enter into the bloodstream. this makes sure glucose is removed quickly

Question 42

what is type 2 diabetes

Answer 42

this is when the pancreas doesnt produce enough insulin or produces so much that insulin doesnt have an affect on them. in this case blood glucose level rises

Question 43

how can type 2 diabetes be controlled

Answer 43

by eating a healthy diet and taking regular excersise

Question 44

what are some adaptations that your body does when your too hot

Answer 44

-erector muscles relax so your hair lies flat -lots of sweat released. when this evaporates, it transfers energy from your skin to the environment -vasodilation happens in the blood vessels near your skin. it allows more blood to flow near the surface so it can transfer more energy into the surroundings which cools you down

Question 45

what are some adaptations that you body does when your too cold

Answer 45

erector muscles contract. hairs stand on end to trap a layer of air which will keep you warm -very little sweat is produced -vasoconstriction occurs meaning less bloodflows near the surface so less energy is transferred to the surroundings -you also shiver which will increase your rate of respiration

Question 46

what happens in the body if the water concentration is too high

Answer 46

the water will move into the cells by osmosis. it too much water moves in, the cell may burst

Question 47

what are the three main roles of the kidneys

Answer 47

-removal of urea -adjustment of ion levels in the blood -adjustment of water content of the blood

Question 48

what are the nephrons

Answer 48

they are the filtration units in the kidneys

Question 49

where in the nephron is the water being reabsorbed

Answer 49

loop of henle

Question 50

how do the nephrons work?

Answer 50

-blood flows into glomerulus-it wont allow RBC or any blood cell or protein to pass- it only allows water, glucose and ura to pass -1st convuluted tuble- glucose reabsorbed by osmosis- has lots of mitochondria -loop of henle- water is reabsorbed by osmosis -collecting duct-water reabsorbed by osmosis by adh

Question 51

what happens when there is not enough water in your body

Answer 51

-your brain detects water loss -pituitary gland releases more ADH(Anti diuretic hormone) -ADH makes kidneys reabsorb more water -this will then rehydrate you

Question 52

what happens when there is too much water in your body

Answer 52

-your brain detects water gain -pituitary gland releases less ADH less ADH means kidney reabsorbs less water - this will decrease amount of water in your body

Question 53

what does a dialysis machine do?

Answer 53

it can be used to filter a persons blood if they have kidney failure

Question 54

what is kidney failure

Answer 54

this is when the patients kidneys cant filter their blood properly

Question 55

how do you use a dialysis machine

Answer 55

the dialysis fluid has the same concentration of salts and glucose as blood plasma. the barrier between the blood is permeable so waste can diffuse out of the blood and into the dialysis fluid. however, they barrier is not big enough for proteins and blood to pass.

Question 56

why does dialysis need to be done regularly

Answer 56

so it can keep the dissolved substances in the right concentration and to remove waste

Question 57

what is the risk of kidney transplants

Answer 57

the donor kidney can be rejected by the patients immune system