B6

Question 1

What sort of condition can enzymes and cells only work in?

Answer 1

very stable conditions, therefore will not work well if the conditions around them change too much

Question 2

Homeostasis?

Answer 2

The regulation of the internal conditions of a cell or organism to maintain optimum conditions for function

Question 3

Example of homeostasis in an athletes body?

Answer 3

to keep the blood glucose levels, temperature and water levels constant

Question 4

3 Features of an automatic control system?

Answer 4

receptor cells

Coordination centre

Effector

Question 5

what do receptor cells do?

Answer 5

Detect changes in the environment (body’s internal conditions)

Question 6

what is a stimulus?

Answer 6

A change to the environment e.g. heat of a candle

Question 7

what is the coordination centre?

Answer 7

Receptor cells now pass information to a coordination centre e.g. brain, spinal cord. it processes the information. now send instructions to the effector.

Question 8

What is an effector?

Answer 8

muscle or gland. It carries out the response and restores the optimum level

Question 9

How do receptors send electrical impulses to the central nervous system?

Answer 9

Through neurones (nerve cells)

Question 10

What is a key role of the nervous system?

Answer 10

enables humans to react to their surroundings and co ordinate their behaviour

Question 11

Endocrine system?

Answer 11

How our body is controlled by hormones

Question 12

What do glands in the endocrine system do?

Answer 12

they secrete hormones directly into the blood, which carries the hormones around the body

Question 13

Which system has a slower effect but a longer lasting effect?
Endocrine system or nervous system?

Answer 13

Endocrine, but the effect is longer lasting

Question 14

What do the hormones that are released from the pancreas do?

Answer 14

they control the concentration of glucose in the blood

Question 15

What sort of hormones do the ovaries and testes release?

Answer 15

hormones involved in puberty and reproduction

Question 16

What sort of hormones do the thyroid glands produce?

Answer 16

hormones involved in growth and how rapidly the body’s reactions take place (neck area)

Question 17

What sort of hormones do adrenal glands release?

Answer 17

adrenaline hormones which is produced in time of fear and stress (lung area)

Question 18

What sort of hormones do the pituitary gland release? (master gland as it is the most important)

Answer 18

a number of different hormones into the blood depending on the condition. They act on other glands, and can trigger a range of different effects in the body

Question 19

What is glucose needed by every cell for and why is this important?

Answer 19

to release energy by respiration, therefore, it is very important that the concentration of glucose in the blood is kept as constant as possible

Question 20

When can blood glucose rise and what happens?

Answer 20

After eating a meal rich in carbohydrates, which then the pancreas releases the hormone insulin which takes away glucose from the blood and stores it (glycogen)

Question 21

What happens to a person with type one diabetes after their glucose concentration rises?

Answer 21

it stays at a high level because the pancreas cannot produce enough insulin

Question 22

what happens to the body cells in people with type 2 diabetes?

Answer 22

the body cells stop responding to insulin produced by the pancreas

Question 23

How can type two diabetes be treated?

Answer 23

with a diet containing a controlled level of carbohydrates

Question 24

what happens if the blood glucose concentration falls e.g. inbetween meals?

Answer 24

then the pancreas releases the hormone glucagon into the bloodstream which triggers liver cells to convert glycogen stores back to glucose

Question 25

What do hormones do when they travelling the bloodstream?

Answer 25

Trigger effects in their specific target organs

Question 26

Ovulation?

Answer 26

every 28 days and egg is released

Question 27

How does period happen?

Answer 27

if the egg does not get fertilised in both the egg and the uterus lining are released

Question 28

what does the follicle stimulating hormone do?

Answer 28

Causes an egg to mature in the ovary

Question 29

what does the luteinising hormone cause the egg to do?

Answer 29

To be released (ovulation)

Question 30

What do the hormones oestrogen and progesterone do?

Answer 30

involved in maintaining the uterus lining in case the egg is fertilised and implants

Question 31

how do all the hormones involved in the menstrual cycle interact?

Answer 31

firstly, FSH is released by the pituitary gland, which travels in the blood to the ovaries, where it causes an egg to mature and triggers the ovaries to make oestrogen, which causes the lining of the uterus to become thick. Now the pituitary gland releases luteinising hormone, which triggers ovulation. Now the ovary produces progesterone

Question 32

What are the 2 effects of progesterone?

Answer 32

it stops the pituitary gland from releasing FSH and LH to prevent any more eggs being released it keeps the lining of the uterus thick in case a fertilised egg implants

Question 33

what happens to the levels of progesterone if fertilisation does not take place?

Answer 33

The level of progesterone falls

Question 34

Contraception?

Answer 34

ways to prevent fertilisation

Question 35

how does the pill work?

Answer 35

They contain hormones, which prevent the body from producing the hormone FSH (which causes an egg to mature

Question 36

advantage and disadvantage of the contraceptive pill

Answer 36

Highly effective if taken correctly Must be taken everyday

Question 37

what other hormonal forms of contraception can be used to prevent progesterone?

Answer 37

implant, skin patch or an injection

Question 38

what do spermicides do?

Answer 38

Kill or disable sperm

Question 39

sterilisation?

Answer 39

surgical forms of contraception

Question 40

what is a fertility drug?

Answer 40

FSH and LH are given to a woman which causes the woman to ovulate more than usual

Question 41

in vitro fertilisation (IVF)?

Answer 41

fertilisation takes place outside the body. firstly, the woman is treated with FSH and LH which causes several eggs to mature. then these eggs and sperm are collected from the parents and used to fertilised eggs in a laboratory. finally, when the embryo is created, they are inserted back into the mothers womb.

Question 42

3 problems with IVF?

Answer 42

The success rate is not very high physically demanding on the mother some embryos will be destroyed, which some people say is unethical

Question 43

Where are the adrenal glands located?

Answer 43

top of the kidneys

Question 44

what does adrenaline cause the body to do?

Answer 44

causes heart to beat faster which means more oxygen and glucose are delivered to the brain and muscles which is needed for aerobic respiration which prepares the body for fight or flight

Question 45

Two Effects of the thyroxine gland?

Answer 45

makes the bodies chemical reactions take place at a faster rate plays an important role in growth and development

Question 46

What is the level of thyroxine in the blood controlled by?

Answer 46

negative feedback

Question 47

Nervous system stages?

Answer 47

Receptor in the skin detects a stimulus (the change in temperature). Sensory neurone sends electrical impulses to relay neurone, which are located in the spinal cord. They connect sensory neurones to motor neurones. Motor neurone sends electrical impulses to an effector. Effector produces a response (muscle contracts to move hand away).

Question 48

What do Insulin and Glucagon do?

Answer 48

Insulin lowers your blood sugar level. Glucagon naturally raises it. Your body uses these two hormones to balance out your blood sugar level to keep it in a healthy range