Human Physiology: Hormones, Homeostasis, and Reproduction

1. [1 mark]

Which hormone inhibits appetite?

A. Epinephrine

B. Leptin

C. Thyroxin

D. Glucagon

2. [1 mark]

What is the name and source of the hormone that regulates basal metabolic rate?

3a. [4 marks]

Reproduction in eukaryotes can be sexual or asexual.

Describe the origin of eukaryotic cells according to the endosymbiotic theory.

3b. [8 marks] 1

Explain how hormones are used to control the human menstrual cycle.

3c. [3 marks]

Outline natural methods of cloning in some eukaryotes.

4. [1 mark]

Which hormone promotes the thickening of the endometrium and also inhibits the hormone that

promotes the development of the follicle wall into the corpus luteum?

A. LH

B. Progesterone

C. FSH

D. Estrogen

5. [1 mark]

The diagram shows the male reproductive organs in front view.

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Which structures are indicated by the letters X, Y and Z?

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6. [1 mark]

Pancreatic gland cells produce and secrete large amounts of digestive enzymes. Which organelles

would you expect to be present in higher than normal amounts in such cells?

A. Free ribosomes and Golgi apparatus

B. Rough endoplasmic reticulum and lysosomes

C. Rough endoplasmic reticulum and Golgi apparatus

D. Free ribosomes and lysosomes

7a. [8 marks]

James Beard, a famous chef, once said “Food is our common ground, a universal experience.”

Explain how the small intestine moves, digests and absorbs food.

7b. [4 marks]

Distinguish between the structures of the different types of fatty acids in food.

7c. [3 marks]

Outline how leptin controls appetite.

8a. [2 marks]

Glands are organs that secrete and release particular chemical substances. Melatonin is an important

hormone secreted in the pineal gland in the brain. Describe its role in mammals.

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8b. [1 mark]

The electron micrograph shows the structures in an exocrine gland cell of the pancreas.

State the principal product of this cell.

8c. [2 marks]

Using the table, identify the organelles labelled I and II on the electron micrograph with their principal

role.

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9a. [1 mark]

In an experiment to determine the effect of diet on response to leptin, mice were fed a control diet or a

high fructose diet for six months and then either injected with a saline (salt) solution or injected with

leptin. The food intake of both groups was then monitored over a 24 hour period.

Distinguish between the effect of leptin injection on 24 hour food intake in the mice fed the control diet

and in the mice fed the high fructose diet.

9b. [2 marks]

Discuss the implications of these results for recommending leptin injections as an appetite suppressant

for humans.

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9c. [1 mark]

Leptin is a hormone. Hormones are chemicals produced in one part of the body that have an effect in

another part of the body.

State the tissue that produces leptin in humans.

9d. [1 mark]

State the target that leptin normally acts on.

10. [1 mark]

Which hormone controls circadian rhythms?

A. Thyroxin

B. Melatonin

C. Leptin

D. Glucagon

11. [1 mark]

Which is a negative feedback mechanism in the menstrual cycle?

A. Follicle stimulating hormone inhibits estrogen

B. Estrogen inhibits luteinizing hormone

C. Estrogen inhibits follicle stimulating hormone

D. Progesterone inhibits estrogen

12. [1 mark]

How can knowledge about the pineal gland function be applied?

A. To restore sleep time by the use of melatonin

B. To trigger ovulation during an IVF treatment

C. To reduce sperm production in male contraception

D. To regulate blood sugar in type I diabetes

13. [1 mark]

How does the hypothalamus respond to a very high body temperature?

A. Increases muscle contraction

B. Stops receiving sensory input

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C. Causes dilation of skin arterioles

D. Slows the heart rate

14. [1 mark]

What is a characteristic of type II diabetes?

A. Insufficient insulin

B. Insulin insensitivity

C. Excess glucagon

D. Low white blood cell count

15. [1 mark]

Which two hormones promote thickening of the endometrium?

A. FSH and LH

B. Estrogen and FSH

C. LH and estrogen

D. Progesterone and estrogen

16a. [2 marks]

Draw a labelled diagram showing the interconnections between the liver, gall bladder, pancreas and

small intestine.

16b. [2 marks]

Outline the role of glucagon in homeostasis of glucose.

16c. [1 mark]

List two examples of polysaccharides.

17. [1 mark]

What happens when human body temperature rises during exercise?

A. The arterioles move closer to the skin.

B. The hypothalamus decreases cell respiration.

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C. The skin capillaries close up.

D. The water from sweat evaporates to cool the body.

18a. [2 marks]

Diabetes is often associated with the failure of the (beta) cells in the pancreas, but it is unclear what βactually causes this failure. FoxO1 is a protein which acts as a transcription factor to regulate the

expression of genes involved in cell growth. FoxO1 also regulates increase in number and

differentiation in cells such as pancreatic cells.β

A study was conducted using mice lacking the gene for FoxO1 in cells (IKO) as well as normal β(control) mice. Blood glucose levels after fasting were compared for four groups of mice: young (3

months old) male mice, young (3 months old) female mice, older females (who have had several

pregnancies) and aging males (16–20 months).

Compare blood glucose levels after fasting in young control mice and young IKO mice without FoxO1.

18b. [1 mark]

Estimate the difference between mean blood glucose levels in control and IKO older female mice.

.................mg ml–1

18c. [2 marks]

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Aging and having pregnancies are considered to be physiological stresses. Deduce the effect of stress on

blood glucose levels.

18d. [2 marks]

Outline the relationship between blood glucose levels after fasting and lack of FoxO1 in the mice

studied.

18e. [1 mark]

The levels of pancreatic hormones and cell mass in older female control mice and older female IKO βmice lacking FoxO1 were then investigated.

State the correlation between lack of FoxO1 and pancreatic hormones in mice.

18f. [3 marks]

Referring to the functions of insulin and glucagon, suggest how the differences in hormone levels help

to explain the blood glucose levels.

19a. [2 marks]

Outline the symptoms of type II diabetes.

19b. [3 marks]

Explain the dietary advice that should be given to a patient who has developed type II diabetes.

20a. [2 marks]

State two symptoms of type II diabetes.

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20b. [4 marks]

Explain the causes and consequences of phenylketonuria (PKU).

21. [1 mark]

The diagram below shows the female reproductive system.

What are the structures indicated by X, Y and Z?

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22. [1 mark]

What is the body’s response to low blood glucose levels?

A. Alpha cells in the pancreas secrete glucagon

B. Beta cells in the pancreas secrete insulin

C. Alpha cells in the pancreas secrete insulin

D. Beta cells in the pancreas secrete glucagon

23a. [2 marks]

Skeletal muscle fibres normally respond to insulin by absorbing glucose. Failure of skeletal muscle to

respond to insulin is a major factor in the development of type II diabetes.

Distinguish between type I and type II diabetes.

23b. [1 mark]

A study was undertaken to investigate the effect of plasma lipids on the process of glucose absorption

in response to insulin by muscle fibers. Muscle was bathed in a lipid solution for 5 hours. The lipid was

then washed out over the next 3 hours. The graph shows the level of plasma fatty acids and the activity

of an enzyme involved in glucose absorption in response to insulin over the period of the study. (Values

are means ± standard error)

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State the relationship between plasma fatty acid level and enzyme activity.

23c. [1 mark]

Calculate the percentage change of enzyme activity after 5 hours exposure to lipids.

23d. [2 marks]

Discuss, using the data, whether the effect of lipids on this enzyme is reversible.

23e. [1 mark]

A further study was undertaken to look at the effect of increasing the concentration of insulin on

glucose absorption in muscle bathed in lipids. A wide range of insulin concentrations were used in the

same type of muscle. Glucose absorption was then measured after 5 hours.

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Calculate the increase in glucose absorption when insulin is increased from 0 to 103 U mlμ –1 for the

muscle bathed in lipid.

_____________________________% of absorption with no insulin

23f. [2 marks]

Comment on the effect of increased insulin concentration on glucose absorption in the muscle bathed in

lipid.

23g. [2 marks]

Some investigators suggest that there is a strong relationship between high lipid diet and the body’s

response to insulin. Using the data provided, evaluate this hypothesis.

24a. [4 marks]

Reproduction can cause populations to increase rapidly. Draw a labelled graph showing a sigmoid

population growth curve.

24b. [6 marks]

Explain the various possible consequences of overproduction of offspring.

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24c. [8 marks]

Outline the role of hormones in the menstrual cycle.

25. [1 mark]

How does the body respond to an increase in body temperature?

I. Vasoconstriction of skin arterioles

II. Shivering

III. Vasodilation of skin arterioles

A. I only

B. I and II only

C. II and III only

D. III only

26. [1 mark]

Oral contraceptives taken by women contain the hormone progesterone. How does this prevent

pregnancy?

A. It stops menstruation.

B. It inhibits the secretion of FSH.

C. It blocks the fallopian tubes (oviducts).

D. It stimulates the production of estrogen.

27. [1 mark]

The diagram shows a feedback pathway.

Which sequence is an example of the pathway?

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28. [1 mark]

What structures are indicated on the diagram?

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29. [1 mark]

LH causes the rupture of a follicle and release of an egg cell. What is this process called?

A. Conception

B. Fertilization

C. Menstruation

D. Ovulation

30a. [6 marks]

Ecologists sometimes display data from an ecosystem using a diagram called a pyramid of energy.

Describe what is shown in pyramids of energy.

30b. [8 marks]

Explain the control of body temperature in humans.

31a. [2 marks]

Outline the control mechanism for appetite in humans.

31b. [3 marks]

Explain the possible health consequences of a diet rich in protein.

32. [2 marks]

List two reasons for increases in the rate of clinical obesity.

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1. ..................................................................

2. ..................................................................

33a. [1 mark]

An investigation was conducted among competitive swimmers to determine the effects of two different

training programmes.

Swimmers were encouraged to maintain an even pace throughout the programmes. The pace was

slightly slower in the 3000 m programme than in the 6000 m programme.

Tissue samples were taken from the shoulder muscle of each swimmer, before and after each session.

Glycogen levels were analysed in slow (type I) muscle fibres.

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Calculate the percentage of slow (type I) muscle fibres that contain low levels of glycogen after the

3000m programme.

33b. [1 mark]

State the effect of the 3000 m programme on glycogen levels in slow (type I) muscle fibres.

33c. [2 marks]

Compare the effects of the 3000 m programme with the 6000 m programme on muscle glycogen levels.

33d. [2 marks]

Suggest reasons for the differences between the 3000 m programme and the 6000m programme in

their effects on muscle glycogen levels.

33e. [1 mark]

Suggest one limitation of the data.

34. [1 mark]

Which of the following are controlled by homeostasis?

I. Blood pH

II. Water balance

III. Blood glucose concentration

A. I and II only

B. I and III only

C. II and III only

D. I, II and III

35. [1 mark]

What is a function of LH (luteinizing hormone)?

A. It stimulates the release of an egg from the follicle.

B. It stimulates the development of corpus luteum into a follicle.

C. It causes an increase in the production of estrogen by the follicle.

D. It causes a decrease in the production of progesterone by the follicle.

36a. [4 marks]

Outline what is meant by homeostasis.

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36b. [6 marks]

Describe how body temperature is maintained in humans.

36c. [8 marks]

Explain the need for a ventilation system and the mechanism of ventilation of the lungs in humans.

37. [1 mark]

Which of the following is a characteristic of type I but not type II diabetes?

A. cells in the pancreas are destroyed.β B. Insulin injections are required.

C. cells in the pancreas are destroyed.α D. Sugar intake control is required.

38. [1 mark]

Which hormone triggers ovulation?

A. FSH

B. Testosterone

C. Progesterone

D. LH

39. [1 mark]

Which words from the table below complete the sentence correctly?

In the pancreas, _____I___ secrete glucagon, which ____II____ blood glucose levels.

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40. [1 mark]

What are causes of type I and type II diabetes?

41. [1 mark]

Which of the following is/are a role of testosterone in males?

I. Pre-natal development of male genitalia

II. Maintenance of sex drive

III. Increase in mental development

A. II only

B. I and II only

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C. II and III only

D. I, II and III

42a. [2 marks]

The graph below shows the levels of hormones during the menstrual cycle.

Identify hormones I and II.

I: ...................................................................

II: ...................................................................

42b. [2 marks]

Outline the roles of FSH in the menstrual cycle.

42c. [1 mark]

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FSH is secreted by the pituitary gland. During pregnancy, FSH secretion is inhibited. Suggest how FSH

secretion could be inhibited during pregnancy.

43a. [2 marks]

Describe the need for a ventilation system in humans.

43b. [2 marks]

Sketch the hormone changes between days 13 and 28 on the graphs below for a woman in her normal

menstrual cycle.

44. [1 mark]

What is a role of the hypothalamus in homeostasis?

A. Monitoring body temperature

B. Monitoring blood glucose concentration

C. Secretion of glucagon

D. Secretion of sweat

45. [1 mark]

What is the sequence of operations during IVF treatment?

A. egg collection → FSH injections → fertilization

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B. egg collection → fertilization → FSH injections

C. FSH injections → egg collection → fertilization

D. FSH injections → fertilization → egg collection

46a. [1 mark]

The diagram below shows the female reproductive system.

Label the diagram above with the letter U to show the uterus.

46b. [1 mark]

Outline the role of luteinizing hormone (LH) after ovulation.

46c. [3 marks]

Explain how sexual reproduction can lead to variation in a species.

47. [1 mark]

What is the correct sequence of events used in IVF?

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48. [1 mark]

What is placed into the uterus after the process of in vitro fertilization (IVF)?

A. Eggs

B. Sperm

C. Embryos

D. Fetuses

49. [3 marks]

Distinguish between type I and type II diabetes.

50a. [5 marks]

Draw a labelled diagram of the adult male reproductive system.

50b. [7 marks]

Describe the role of sex chromosomes in the control of gender and inheritance of hemophilia.

50c. [6 marks]

Discuss the ethical issues associated with IVF.

Printed for Pritzker College Prep

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