HORMONAL COORDINATION (11)

Question 1

What is the endocrine system?

Answer 1

Made up of glands that secrete chemicals called hormones directly into the bloodstream. The blood carries the hormone to a specific organ where it produces an effect. The target organ has receptors on the cell membranes that pick up the hormone molecules, triggering a response in the cell.

Question 2

What is the pituitary gland?

Answer 2

Acts as a master gland. It secretes a variety of different hormones into the blood in response to changes in the body conditions. It is found in the brain.

Question 3

What is FSH?

Answer 3

Follicle stimulating hormone which stimulates the ovaries to make the female sex hormone oestrogen.

Question 4

What is TSH?

Answer 4

Stimulates the thyroid gland to make thyroxine, a hormone that helps control the rate of your metabolism.

Question 5

What is the role of the pituitary gland?

Answer 5

Controls growth in children
Stimulates the thyroid gland to make thyroxine to control the rate of metabolism.
Stimulates the ovaries to produce and release eggs and make the female sex hormone oestrogen.
Stimulates the testes to make sperm and the male sex hormone testosterone.

Question 6

What is the role of the thyroid gland?

Answer 6

Controls the metabolic rate of the body.

Question 7

What is the role of the pancreas gland?

Answer 7

Controls the level of glucose in the body.

Question 8

What is the role of the adrenal gland?

Answer 8

Prepares the body for stressful situations - fight or flight response.

Question 9

What is the role of the ovaries (gland)?

Answer 9

Controls the development of the female secondary sexual characteristics and is involved in the menstruated cycle.

Question 10

What are the testes (gland)?

Answer 10

Controls the development of the male secondary sexual characteristics and is involved in the production of sperm.

Question 11

What does insulin do?

Answer 11

When your blood glucose levels rise after eating, the pancreas produces insulin. Insulin allows glucose to move from the blood into your cells where it is used.
Soluble glucose is also converted into insoluble carbohydrates called glycogen. Insulin controls the storage of glycogen in your liver and muscles.
Stored glycogen can be converted back into glucose when it is needed. As a result, your blood glucose levels stays stable with a narrow concentration range.

Question 12

What is glucagon?

Answer 12

When your blood glucose levels fall, the pancreas secretes another hormone called glucagon. Glucagon makes your liver breakdown glycogen, converting it back into glucose. In this way, the stored glucose is released back into the blood.

Question 13

What causes type 1 diabetes?

Answer 13

If your pancreas doesn’t make enough insulin, your blood glucose concentration is not controlled. This means you have type one diabetes.
Without insulin, your blood glucose levels get very high after you eat. Eventually, your kidneys excrete glucose in the urine. You will produce lots of urine and feel thirsty all the time. Without insulin, glucose can not get into the cells in the body, so you will lack energy and feel tired. You break down fat and protein instead, so will lose weight.

Question 14

What is type 2 diabetes?

Answer 14

Often linked to obesity and a lack of exercise. There is a string generic tendency. With type 2 diabetes, the pancreas still secretes insulin, although it may be less than your body needs. Your body cells stop responding to the insulin you make.

Question 15

How can type 1 diabetes be treated?

Answer 15

Injecting insulin before meals. It must be injected otherwise the stomach would digest it as it is a protein. The injected insulin allows glucose to be taken into your body cells and converted to glycogen in the liver.

Need to be careful about the amount of consumption of carbohydrates.
Regular meals.
Planned exercise.

Question 16

What are some possible cures for type one diabetes?

Answer 16

Pancreas transplant.
Transplanting the pancreatic cells that make the insulin from both dead and living donors has been tried, with limiting success so far.

Question 17

How can type 2 diabetes be treated?

Answer 17

Eating a balanced diet with carefully controlled a,lungs of carbohydrates.
Losing weight.
Doing regular exercise.

Drugs to help insulin work better in the body cells.
To make pancreas make more insulin.
Reduce the amount of glucose you absorb from your gut.

Question 18

What is negative feedback?

Answer 18

Negative feedback systems work to maintain a steady state.
If a factor in the internal environment increases, changes take place to reduce it and restore it to the original level. Vice versa.

Question 19

What does adrenaline do?

Answer 19

Causes your heart and breathing rate to increase.
Stored glycogen in the liver is converted to glucose for respiration.
The pupils of your eyes dilated to let in more light.
Your mental awareness increases.
Blood is diverted away from your digestive system to the big muscles of the limbs.

Question 20

What hormones are involved in the menstrual cycle?

Answer 20

FSH - follicle stimulating hormone causes the eggs in the ovary to mature

LH - luteinising hormone stimulates the release of the egg at ovulation.

Oestrogen and progesterone stimulate the build-up and maintenance of the uterus lining.

Question 21

How is the menstrual cycle controlled?

Answer 21

FSH makes eggs mature in their follicles in the ovaries and stimulates the ovaries to produce hormones including oestrogen.

Oestrogen is secretes in response to FSH. It stimulates the lining of the uterus to grow again after menstruation in preparation for pregnancy. High levels of oestrogen inhibit the production of FSH and stimulate the release of LH.

LH stimulates the release of a mature egg from the ovary. Once ovulation has taken place, LH levels falls again.

Progesterone hormone is secreted by the empty egg follicle. It helps maintain a pregnancy is the egg is fertilised. It inhibits both FSH and LH and it maintains the lining of the uterus in the second half of the cycle, so that it is ready to receive a developing embryo if the egg is fertilised.

Question 22

What is IVF?

Answer 22

Doctors give the mother synthetic FSH to stimulate the maturation of a number of eggs at the same time, followed by LH to bring the eggs to the point of ovulation.
They collect the eggs from the mother and fertilise them with sperm from the father outside the body in the laboratory.
The fertilised eggs are kept in special solutions in a warm environment to develop into tiny embryos.
One or two of the embryos are inserted back into the uterus of the mother. In this way, they bypass the faulty tubes.

Question 23

What are the advantages of fertility treatment?

Answer 23

Gives people the chance to have a baby, who otherwise might not be able to.

Question 24

What are some disadvantages of fertility treatment?

Answer 24

Expensive.
Not always successful.
Possible health risks.
Increases the chance of multiple pregnancies.

Question 25

What are tropisms?

Answer 25

The response of plant roots and shoots to light and gravity.
Tropic response.

Question 26

What is phototropism?

Answer 26

The response of a plant to light is known as a phototropism.

Question 27

What is gravitropism?

Answer 27

The response of a plant to gravity is called gravitropism (or geotropism).

Question 28

What is auxin?

Answer 28

A plant hormone that controls growth. The response to the tropism happens as a result of an uneven distribution or this hormone in the shoot or root.

Question 29

Why do shoots grow downwards?

Answer 29

The roots grow on the side with least auxin, making it bend and grow down.

Question 30

Where does most auxin gather in shoots and roots?

Answer 30

The underside.

Question 31

How can auxins be used?

Answer 31

Rooting powder.

Weed killers - sends the plant into uncontrolled growth, killing them. Crops are mainly unaffected due to their smaller surface area, compared to weeds. Known as selective herbicides.

Question 32

How can gibberellins be used?

Answer 32

Brewing industry to end seed dormancy.
Used to promote flowering throughout the year.
Widely used to increase the size of fruit.

Question 33

How can ethane be used?

Answer 33

Widely used to control the ripening of fruit.