Topic 7 Animal Coordination, Control and Homeostasis

Question 1

What are hormones?

Answer 1

Chemical messengers

Question 2

How are hormones sent around the body?

Answer 2

Hormones are directly released in to the blood

Question 3

What do the hormones effect?

Answer 3

The target organ

Question 4

Where are hormones produced?

Answer 4

Glands
Endocrine glands that make up the endocrine system

Question 5

What does the pituitary gland do?

Answer 5

Regulates body conditions
Can also control other glands production of hormones

Question 6

What does the thyroid produce and do?

Answer 6

Produces thyroxine that regulates the rate of metabolism, heart rate and temperature

Question 7

What does the adrenal gland produce and do?

Answer 7

Produces adrenaline for a ‘flight or fight’ response

Question 8

What does the pancreas release and why?

Answer 8

Produces insulin to regulate blood glucose levels

Question 9

What do the ovaries produce?

Answer 9

Produces oestrogen involved in the menstrual cycle

Question 10

What do the testes produce.

Answer 10

Produces testosterone controlling puberty and sperm production

Question 11

What is the differences between nerves and hormones?

Answer 11

Nerves- very fast, act in a short time, precise area
Hormones- slower action, long lasting, general area

Question 12

What does adrenaline do in the heart?

Answer 12

Binds to specific receptor
Causes the muscle to contract more frequently with more force, increasing blood pressure
Increases blood flow= more respiration

Question 13

What does adrenaline do in the liver?

Answer 13

Binds to receptors
Causes the break down of glycogen to release glucose
Increases blood glucose levels

Question 14

What is negative feedback?

Answer 14

When the body detects that the level of a substance has gone above or below normal levels, it triggers a response to bring it back to normal

Question 15

What happens when blood thyroxine levels are too low?

Answer 15

Hypothalamus stimulates a release of TRH
TRH stimulates the pituitary gland to release TSH
TSH stimulates the thyroid gland to release thyroxine

Question 16

What happens when blood thyroxine levels are too high?

Answer 16

The hypothalamus stops the production of TRH
Which reduces the production TSH
Thus lowering thyroxine levels back to normal

Question 17

What is the menstrual cycle?

Answer 17

The monthly release of an egg

Question 18

What happens in stage 1 of the menstrual cycle.

Answer 18

The lining of the uterus breaks down

Question 19

What happens in stage 2 of the menstrual cycle?

Answer 19

The uterus lining builds back up
Thick and spongy
Ready for a fertilised egg to implant

Question 20

What happens in stage 3 of the menstrual cycle?

Answer 20

An egg develops and is released from the ovaries

Question 21

What happens in stage 4 of the menstrual cycle?

Answer 21

The lining is maintained for 14 days, until day 28
If no fertilised is implanted, the lining starts to break down and the cycle starts again

Question 22

What 4 hormones control the menstrual cycle?

Answer 22

FSH
Oestrogen
LH
Progesterone

Question 23

What does FSH do?

Answer 23

Causes an egg to mature
Stimulates oestrogen production

Question 24

What does oestrogen do?

Answer 24

Causes the lining of the uterus to thicken and grow
High level=LH surge

Question 25

What does LH do?

Answer 25

LH surge stimulates ovulation Remains of the follicle to develop into corpus luteum

Question 26

What does the corpus luteum release?

Answer 26

Progesterone

Question 27

What does progesterone do?

Answer 27

Maintins lining of the uterus Stops the release of FSH and LH

Question 28

What happens when progesterone levels fall?

Answer 28

Oestrogen levels fall Uterus lining breaks down Low progesterone levels allows FSH to increase Cycle starts again

Question 29

What happens when a fertilised egg is implanted?

Answer 29

Progesterone levels stay high to maintain the lining throughout pregnancy

Question 30

What can a permanently high oestrogen do?

Answer 30

Prevents the production of FSH Stoping egg development and production after a while

Question 31

What can thicken cervical mucus? And why?

Answer 31

Progesterone To prevent sperm getting through

Question 32

What is homeostasis?

Answer 32

Maintaining a constant internal environment

Question 33

What is glycogen?

Answer 33

A store to glucose in the liver and muscles

Question 34

What happens to excess glucose that cannot be stored as glycogen?

Answer 34

Stored as lipids in the tissues

Question 35

What is added when glucose concentration is too high?

Answer 35

Insulin is released from the pancreas

Question 36

What is added when glucose concentration is too low?

Answer 36

Glucagon is released from the pancreas

Question 37

What is type 1 diabetes?

Answer 37

A lack of insulin

Question 38

How can type 1 diabetes be treated?

Answer 38

Insulin therapy, injecting insulin

Question 39

What do people with type 1 diabetes need to think about?

Answer 39

Limiting food intake Taking regular exercise, helps remove excess glucose

Question 40

What is type 2 diabetes?

Answer 40

When a person is resistant to insulin

Question 41

What increases the risk of developing type 2 diabetes?

Answer 41

Being obese BMI over 30

Question 42

How is BMI calculated?

Answer 42

Mass/height ²

Question 43

What is thermoregulation?

Answer 43

The process you body uses to keep its internal temperature steady

Question 44

Where is the thermoregulatory centre located?

Answer 44

In the hypothalamus

Question 45

Why does body temperature need to be kept at a constant?

Answer 45

For enzymes to work at there best. Too cool- slows them down Too hot- cause denaturing and to not work at all

Question 46

What happens when you are too hot?

Answer 46

Erector muscles relax- hairs lie flat Sweat glands- lots of sweat which can be evaporated transferring the energy to the environment Blood vessels dilate (vasodilation)- widen for more blood flow to the surface to transfer more of the energy out

Question 47

What happens when you are too cold?

Answer 47

Erector muscles contract- hairs stand up trapping a layer of insulating air near the surface Very little sweat produced Blood vessels constrict (vasoconstriction)- less blood flow, less energy transfered Shivering- muscles contracting, increases rate of respiration, transferring more energy in