(outdated) Aspects of Human Reproduction

With reference to Fig. 6.1, explain why there is a large increase in LH at around day 12.

State how Fig. 6.1 shows that the woman did not become pregnant during this cycle.

Explain how this combined contraceptive pill works to prevent pregnancy.

Suggest why some women take the combined contraceptive pill for just the first 21 days of their cycles.

Some women have a contraceptive device inserted under the skin. This releases hormones into the blood and can last for up to three years.

Suggest one advantage of using such a device rather than taking contraceptive pills.

With reference to Fig. 6.1, explain why there is a large increase in LH at around day 12.

State how Fig. 6.1 shows that the woman did not become pregnant during this cycle.

Explain how this combined contraceptive pill works to prevent pregnancy.

Suggest why some women take the combined contraceptive pill for just the first 21 days of their cycles.

Some women have a contraceptive device inserted under the skin. This releases hormones into the blood and can last for up to three years.

Suggest one advantage of using such a device rather than taking contraceptive pills.

With reference to Fig. 6.1, state the letter of the stage of the cycle during which ovulation occurs.

State how Fig. 6.1 shows that the woman did not become pregnant during this cycle.

Name the ovarian structure that secretes progesterone after ovulation.

State the role of progesterone during stage D.

The combined contraceptive pill contains oestrogen and progesterone.

Explain how this combined contraceptive pill works to prevent pregnancy.

Outline how the oestrogen/progesterone contraceptive pill works to prevent pregnancy.

Discuss the biological, ethical and social implications of using this contraceptive pill.

Outline how the oestrogen/progesterone contraceptive pill works to prevent pregnancy.

Discuss the biological, ethical and social implications of using this contraceptive pill.

Outline oogenesis in a human female.

Describe and explain the changes to the uterus during the menstrual cycle.

On Fig. 4.1, state whether each of the labelled cells is haploid or diploid.

Write n if the cell is haploid and 2n if the cell is diploid.

Spermatogenesis involves meiosis, mitosis, growth and maturation.
State which of these processes is involved in each of the following steps in spermatogenesis.

spermatogonium to primary spermatocyte

______

spermatid to spermatozoan (sperm)

______

State one role of a Sertoli cell.

In some men, spermatogenesis does not take place successfully and the sperm that are produced are unable to fertilise an egg. A form of IVF called intra-cytoplasmic sperm injection (ICSI) may enable them to father a child with their partner.

In ICSI, a sperm cell is inserted into a secondary oocyte using a very tiny needle.

Outline the treatment required in order to obtain mature oocytes as part of an IVF procedure.

With reference to Table 4.1, describe the effects of adding reproductive hormones on the development of the spermatids after 48 hours.

Suggest a reason for the apparent reduction in the percentage of elongated cells between 24 hours and 48 hours in some of the samples.

Suggest why the culture medium was maintained at a temperature of $30\ ^{\circ}\text{C}$, and not at core body temperature ($37\ ^{\circ}\text{C}$).

On Fig. 4.1, state whether each of the labelled cells is haploid or diploid.

Write n if the cell is haploid and 2n if the cell is diploid.

Spermatogenesis involves meiosis, mitosis, growth and maturation. State which of these processes is involved in each of the following steps in spermatogenesis.

spermatogonium to primary spermatocyte

______

spermatid to spermatozoan (sperm)

______

State one role of a Sertoli cell.

In some men, spermatogenesis does not take place successfully and the sperm that are produced are unable to fertilise an egg. A form of IVF called intra-cytoplasmic sperm injection (ICSI) may enable them to father a child with their partner.

In ICSI, a sperm cell is inserted into a secondary oocyte using a very tiny needle.

Outline the treatment required in order to obtain mature oocytes as part of an IVF procedure.

With reference to Table 4.1, describe the effects of adding reproductive hormones on the development of the spermatids after 48 hours.

Suggest a reason for the apparent reduction in the percentage of elongated cells between 24 hours and 48 hours in some of the samples.

Suggest why the culture medium was maintained at a temperature of $30\ ^{\circ}\text{C}$, and not at core body temperature ($37\ ^{\circ}\text{C}$).

Outline the technique of in-vitro fertilisation (IVF).

Discuss the ethical implications of IVF.

As part of the technique of In-vitro fertilisation (IVF), several oocytes are collected from a woman who is undergoing treatment. Each oocyte is checked under a microscope.

Explain why oocytes that have a first polar body are used in the fertilisation process.

When the oocytes were placed into solution A or solution B, they quickly reduced in size. Explain why this happened.

Table 5.1 shows the results of the trial.

Table 5.1

With reference to Table 5.1, explain which solution is the better solution to use.

Suggest one advantage of being able to freeze and thaw oocytes as part of the IVF procedure.