The human endocrine system

Human growth hormone (hGH) is made by the pituitary gland.

Name one other hormone made by the pituitary gland.

hGH is a protein.

A child with a deficiency of hGH can be given injections of hGH.

What would happen to the hGH if it was given as a tablet that was swallowed?

Scientists can use genetic engineering to make hGH.

Figure 4 shows a summary of the process.

Describe how scientists can transfer the gene for hGH from human cells to bacterial cells.

Use information from Figure 4.

Growth hormone (GH) can be extracted from the urine of farm animals.

It is better to use hGH made by genetic engineering than to use GH from the urine of farm animals.

Suggest two reasons why.

Do not refer to ethical reasons or religious beliefs in your answer

The human body has two coordination systems:

• the nervous system

• the endocrine system.

Two students investigated human reaction time.

Student A held a metre rule above student B ’s hand.

Student A then released the metre rule and student B caught the rule as quickly as possible.

Figure 8 shows the method used.

Suggest two ways to improve the students’ method for measuring human reaction time.

Student B ’s reaction is coordinated by the nervous system.

Give two ways that coordination by the endocrine system is different from coordination by the nervous system.

Figure 9 shows endocrine glands in a female.

Name one hormone produced by gland A.

Name one hormone produced by gland B.

The adrenal gland produces the hormone adrenaline.

Describe two effects of adrenaline on the human body.

Hormones can be used for controlling human reproduction.

Explain the use of hormones in:

• contraception

• the treatment of infertility.

Hormones are important for controlling many processes in the human body.

Hormones are produced by glands.

Which organ system has glands that produce hormones?

Tick (✓) one box.

How are hormones transported around the body?

Tick (✓) one box.

Figure 1 shows glands in a woman’s body.

Draw one line from each gland to the name of that gland.

Which gland in Figure 1 produces insulin?

Tick (✓) one box.

Which organ does insulin mainly affect?

Tick (✓) one box.

Give one effect of insulin.

Some hormones control a woman’s menstrual cycle.

Which hormone causes an egg to mature in the ovary?

Tick (✓) one box.

Which two are hormones that help to maintain the lining of the uterus during pregnancy?

Tick (✓) two boxes.

Contraception prevents pregnancy.

Give two methods of contraception that use hormones.

Homeostasis is the regulation of the body’s internal conditions. Many internal conditions are controlled by hormones. Homeostasis works by negative feedback control.

Figure 8 shows how the concentration of substance Q in the blood is controlled by negative feedback.

Explain how the concentration of substance Q in the blood is controlled by negative feedback. Use information from Figure 8.

Thyroxine is a hormone produced by the thyroid gland. A decrease in body temperature causes an increase in thyroxine production. Explain how the production of thyroxine causes an increase in body temperature.

ADH is a hormone made by the pituitary gland. ADH controls how much water is reabsorbed from the kidney tubules. Table 2 shows effects of ADH.

The concentration of ADH in a man’s blood was 3.75 nanograms/dm³. The concentration of ADH in his blood decreased to 1.25 nanograms/dm³. Explain how the decrease in the concentration of ADH would cause the changes to the urine shown in Table 2.

Many internal processes of the human body are controlled by hormones. Hormones are produced by glands. Figure 2 shows glands in a woman’s body.

Which gland is the pituitary gland?

Tick (✓) one box.

Which gland is the pancreas?

Tick (✓) one box.

The hormone insulin helps to decrease the blood glucose concentration. Insulin causes its target organs to take in glucose from the blood.

Which of the following is a target organ for insulin?

Tick (✓) one box.

The glucose is stored as an insoluble substance. What is the insoluble storage substance that is formed from glucose?

Tick (✓) one box.

Scientists investigated the effect of a glucose drink on the concentration of glucose in

a person’s blood. This is the method used.

1. Take a small sample of blood from the person.

2. Measure the concentration of glucose in the person’s blood.

3. Give the person a drink containing 50 grams of glucose.

4. Measure the concentration of glucose in the person’s blood at intervals.

5. Calculate the change in blood glucose concentration from the starting value.

Figure 3 shows the results.

Figure 3 shows the change in blood glucose concentration.

At the start of the investigation, the blood glucose concentration was 5 mmol/dm³. Calculate the highest blood glucose concentration during the investigation. Use information from Figure 3 in your answer.

What is the time taken for the blood glucose concentration to decrease from its highest value back to the starting value? Use data from Figure 3 in your answer.

Why can you not be certain that your answer to Question 02.6 is accurate?

Figure 3 shows the results for a person who does not have Type 2 diabetes. Sketch a line on Figure 3 to show the results you would expect for a person who has

Reflex actions are coordinated by the nervous system.

What is meant by the term ‘reflex action’?

A woman’s hand accidentally touches a hot object. The woman moves her hand away rapidly. Describe how the woman’s nervous system coordinates the reflex action.

The endocrine system coordinates many internal functions of the body. Give three ways coordination by the endocrine system is different from coordination by the nervous system.

Describe how hormones control the menstrual cycle.