Contraception

Figure 9 shows a human egg cell viewed using a light microscope.

In Figure 9, the diameter of the image of the egg is 38 mm.

The magnification of Figure 9 is × 400

Calculate the real diameter of the egg cell in micrometres.

Use the equation:

1 millimetre = 1000 micrometres

Real diameter of egg cell = _____________________ micrometres

Draw a simple diagram of the egg cell shown in Figure 9.

On your drawing:

$l~bel two parts of the egg cell that are visible in Figure 9

$do not include other cells.

Some parts of a human egg cell are not visible in Figure 9.

Name one part of a human egg cell that is only visible using an electron microscope.

Name the process of cell division that produces egg cells.

How many chromosomes are in a human egg cell?

Describe how a chromosome in a sperm cell determines whether the offspring that forms is male or female.

Which hormone stimulates the release of an egg?

Tick () one box.

FSH

LH

Oestrogen

Oral contraceptive pills contain hormones that prevent the release of an egg.

Scientists studied the effectiveness of different types of contraception with perfect use and with use in real life.

‘Perfect use’ means following all the instructions.

‘Use in real life’ is what actually happens in the population. The instructions may not always be followed in real life.

Figure 10 shows the results.

Evaluate the effectiveness of the three types of contraception shown in Figure 10.

Use data from Figure 10.

Figure 1 shows a human egg cell viewed using a light microscope.

In Figure 1, the diameter of the image of the egg is 38 mm.

The magnification of Figure 1 is × 400

Calculate the real diameter of the egg cell in micrometres.

Use the equation:

1 millimetre = 1000 micrometres

Real diameter of egg cell = _____________________ micrometres

Draw a simple diagram of the egg cell shown in Figure 1.

On your drawing:

$l~bel two parts of the egg cell that are visible in Figure 1

$do not include other cells.

Some parts of a human egg cell are not visible in Figure 1.

Name one part of a human egg cell that is only visible using an electron microscope.

Name the process of cell division that produces egg cells.

How many chromosomes are in a human egg cell?

Describe how a chromosome in a sperm cell determines whether the offspring that forms is male or female.

Which hormone stimulates the release of an egg?

Tick () one box.

FSH

LH

Oestrogen

Oral contraceptive pills contain hormones that prevent the release of an egg.

Scientists studied the effectiveness of different types of contraception with perfect use and with use in real life.

‘Perfect use’ means following all the instructions.

‘Use in real life’ is what actually happens in the population. The instructions may not always be followed in real life.

Figure 2 shows the results.

Evaluate the effectiveness of the three types of contraception shown in Figure 2.

Use data from Figure 2.

Chlamydia, HIV and human papillomavirus (HPV) are sexually transmitted diseases (STDs).

Which other disease is sexually transmitted?

Tick (✓) one box.

Flu

Gonorrhoea

Malaria

Measles

Students were asked to estimate the percentage risk of a person becoming infected with different STDs.

The estimate was compared to the actual percentage risk of infection.

Figure 7 shows the results.

The students estimated that the risk of HIV infection was 60%.

Plot the students’ estimated risk of HIV infection on Figure 7.

Which STD in Figure 7 shows the greatest actual risk?

Calculate the difference between the estimated risk and the actual risk of becoming infected with chlamydia.

What conclusion can be made about the estimated risk of infection compared to the actual risk of infection with STDs?

Name one type of contraception that can control the spread of chlamydia.

Patients with HPV infections are at increased risk of cancer.

Suggest what effect HPV has on human DNA.

This question is about health.

Some pathogens cause food poisoning.

Explain how the stomach is adapted to prevent food poisoning.

Different types of disease may interact.

Suggest one type of disease that may be triggered by infection with human papillomavirus (HPV).

Chlamydia, HIV and HPV are sexually transmitted diseases (STDs).

Chlamydia is caused by the same type of microorganism as gonorrhoea.

Suggest how chlamydia infections are treated.

One symptom of chlamydia infection is damage of the uterus lining.

Which two hormones are involved in maintaining the uterus lining?

Students were asked to estimate the percentage risk of a person becoming infected with different STDs.

` The estimate was compared to the actual percentage risk of infection.

Figure 8 shows the results.

Figure 8

Why is the data in Figure 8 plotted as a bar chart and not as a line graph?

The difference between the estimated risk and the actual risk is not the same for each STD.

Suggest two reasons why.

Explain how only some types of contraception reduce the spread of STDs.

Explain why patients with late-stage HIV infection or AIDS are likely to become very ill from other infections.

This question is about hormones.

Draw one line from each hormone to the function of that hormone.

In one menstrual cycle, an egg is released on day 13.

Which chemical causes the egg to be released?

Tick (✓) one box.

Cholesterol

Insulin

Lipase

Luteinising hormone

Hormones are used in some methods of contraception.

Which two types of contraception use hormones?

Tick (✓) two boxes.

Condom

Diaphragm

Oral contraceptive pill

Skin patch

Surgical sterilisation

Figure 5 shows how a baby is formed.

Use Figure 5 to answer questions 04.4 to 04.6.

Name the process happening at A.

The sperm and egg were formed by meiosis.

Meiosis is a type of cell division.

Name the type of cell division happening at B.

At C the cells are stem cells.

Explain how the stem cells become cells that can carry nervous impulses.

This question is about hormones and reproduction.

Hormones are used in some methods of contraception.

Give two types of contraception that use hormones.

Figure 6 shows some of the hormones involved in the menstrual cycle.

Which hormone peaks on day 13?

Use Figure 6.

Tick (✓) one box.

Follicle stimulating hormone

Luteinising hormone

Oestrogen

Progesterone

What is the function of hormone Q ?

Use Figure 6.

Tick (✓) one box.

Causes an egg to mature

Maintains the uterus lining

Stimulates release of the egg

The number of twins born increased from the year 1980 to the year 2013.

Approximately two-thirds of twins born in the UK are not identical twins.

Suggest how non-identical twins are formed.

Explain how one type of treatment for infertility could have caused the increase in the number of twins born between 1980 and 2013.

This question is about contraception.

Draw one line from each method of contraception to how the method works.

Which method of contraception can protect against sexually transmitted diseases?

Tick (✓) one box.

The oral contraceptive pill has to be taken every day to be effective.

Suggest one reason why a woman taking the oral contraceptive pill may become pregnant.

Surgical sterilisation is another method of contraception.

Suggest one disadvantage of surgical sterilisation compared with taking the oral contraceptive pill.

Suggest two reasons why a man and a woman in a sexual relationship might choose not to use contraception.

Do not refer to surgical sterilisation in your answer.