B11. Hormonal Control

Question 1

What is homeostasis?

Answer 1

Homeostasis is the regulation of the internal conditions of a cell or organism to maintain optimum conditions for function in response to internal and external changes.

Question 2

Define a gland

Answer 2

A gland is any organ that releases hormones

Question 3

Define a hormone

Answer 3

A hormone is a chemical produced by a gland secreted into the bloodstream
where it travels in the blood to a target organ where a response occurs.

Question 4

The pituitary gland is know as the ‘master gland’. Which hormones does the pituitary gland secrete?

Answer 4

Follicle stimulating hormone (FSH)

Luteinising hormone (LH)

Question 5

Name the hormones that the pancreas gland secretes?

Answer 5

Insulin and glucagon

Question 6

Which hormone is secreted by the thyroid gland and what is it’s function.

Answer 6

Hormone = Thyroxine
It controls metabolic rate and affects growth

Question 7

Which hormone is secreted by the adrenal glands?

Answer 7

Adrenaline

Question 8

What is the function of the hormone adrenaline?

Answer 8

It increases the heart rate and
boosts the delivery of oxygen and glucose to the brain and muscles preparing the body for ‘flight or fight’.

Question 9

Explain how insulin regulates blood glucose levels?

Answer 9

Insulin lowers blood glucose levels by stimulating the liver and muscle cells to take in excess glucose and store it as glycogen.

Question 10

Which gland detects changes in blood glucose levels?

Answer 10

Pancreas

Question 11

Explain how the hormone glucagon causes blood glucose levels to rise.

Answer 11

Glucagon travels in the bloodstream to the liver (where there is a store of glucose).
The liver converts stored glycogen back into glucose.
Blood glucose levels therefore rise.

Question 12

Which type of feedback controls blood glucose levels?

Answer 12

Negative feedback

Question 13

What is meant by the term ‘negative feedback’?

Answer 13

Negative feedback involves a response that is thereverseof the change detected (it functions toreducethe change).

Question 14

What is Type 1 diabetes?

Answer 14

Type 1 diabetes is a disorder in which the pancreas fails to produce sufficient insulin.

Question 15

How might a Dr become aware that a patient has type 1 diabetes?

Answer 15

It is characterised by uncontrolled high blood glucose levels.
The patient may have glucose in their urine.

Question 16

What is the treatment for type 1 diabetes?

Answer 16

It is normally treated with insulin injections (usually via insulin pump).

Question 17

What is type 2 diabetes?

Answer 17

Type 2 diabetes is a disorder where the body cells no longer respond to insulin produced by the pancreas. So excess glucose is not absorbed.

Question 18

How is type 2 diabetes usually controlled?

Answer 18

A carbohydrate controlled diet and an exercise regime are common treatments.

Question 19

Name 3 symptoms of both type 1 and type 2 diabetes.

Answer 19

Frequent urination
Being really thirsty
Blurred vision

Question 20

Name 2 risk factors for type 2 diabetes.

Answer 20

Lack of exercise
Obesity
Family history
Diet high in saturated fat

Question 21

What is the function of the hormone FSH in controlling the menstrual cycle?

Answer 21

• it causes an egg to mature in an ovary.
• it stimulates the ovaries to release the hormone oestrogen.

Question 22

What is the function of the hormone Oestrogen in controlling the menstrual cycle?

Answer 22

• Stimulates the lining of the uterus to grow ‘build up’ again after menstruation in preparation for pregnancy.
• Stimulates the pituitary gland to release LH.
• Inhibits the release of FSH, so that only one egg matures in a cycle.

Question 23

What is the function of the hormone LH in controlling the menstrual cycle?

Answer 23

• Stimulates the release of a mature egg from the ovary.
• Stimulates the ovaries to release progesterone.
• Inhibits the release of Oestrogen.

Question 24

What is the function of the hormone progesterone in controlling the menstrual cycle?

Answer 24

• Maintains the lining of uterus during second half of menstrual cycle and during pregnancy.
• Inhibits both FSH and LH.

Question 25

What is infertility?

Answer 25

Infertility means being unable to conceive.

Question 26

Name 2 possible causes of infertility?

Answer 26

• Problems with ovulation
• Low sperm count
• Male infertility
• Block fallopian tubes
• Underlying medical conditions

Question 27

Which fertility drugs are given to women during IVF treatment?

Answer 27

Fertility drugs given to women are FSH and LH by injection.

Question 28

What are the stage of IVF treatment?

Answer 28

IVF involves giving the mother fertility drugs (FSH and LH) to stimulate the maturation of several eggs.

The eggs are collected from the mother by a doctor and fertilised by sperm from the father in the laboratory.

The fertilised eggs divide and develop into embryos.

At the stage when they are tiny balls of cells, one or two embryos are inserted into the mother’s uterus (womb).

Question 29

List 3 disadvantages of IVF treatment.

Answer 29

• Low success rate (approx 20-30%)ornot always successful
  *High number of multiple births (can lead to low birth weight or harm to mother)
  *Expensive
  *Emotionally and physically stressful
  *Side effects