16.4. Sexual reproduction in humans
A subsection of Biology, 0610, through 16. Reproduction
Listing 10 of 229 questions
For Examiner's Use The egg cell is the female gamete. shows an ovum at the time of ovulation. The ovum is surrounded by a ‘jelly coat’ and many follicle cells. 0.14 mm egg cell ‘jelly coat’ follicle cells Calculate the magnification of the egg cell as shown in . Show your working and express your answer to the nearest whole number. answer = State three ways in which the structure of an egg cell, as shown in , differs from the structure of a sperm cell. Meiosis is involved in the production of male and female gametes. Explain why it is important that meiosis occurs during the production of gametes. For Examiner's Use Some women are unable to become pregnant because they or their partner are infertile. Suggest one reason why a man may be infertile and one reason why a woman may be infertile. man woman One way to treat infertility in a woman is to use artificial insemination (Ausing her partner’s sperm. The stages involved in AI are as follows. 1. If the doctor decides that AI is suitable, the woman will be given a course of a fertility drug at an appropriate stage of her menstrual cycle. 2. After two weeks, ultrasound is used to find out when the woman is likely to ovulate. 3. Sperm are collected from the man. 4. The sperm are placed into the uterus of the woman near the time of ovulation. 5. The woman is given an injection of a hormone to encourage the corpus luteum in the ovary to secrete progesterone. Explain why the sperm must be placed in the uterus near the time of ovulation. For Examiner's Use Explain why it is important that progesterone is secreted after ovulation. The success rate of AI is about 16 %. Suggest how the success rate of AI is calculated.
0610_s12_qp_33
THEORY
2012
Paper 3, Variant 3
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is a flow diagram showing the events that occur to form a human fetus. haploid egg cell diploid cell ovary organ P process Q process R process T process U haploid sperm cell diploid cell diploid cell S embryo fetus Complete Table 6.1 by using the information in the flow diagram to identify the cell, the organ and the processes shown in . Table 6.1 cell, organ or process name of the cell, organ or process organ P cell S process Q produces haploid sperm and eggs process R produces diploid cell S process T occurs so that cell S can grow into an embryo process U occurs so that the embryo can gain oxygen and nutrients from the mother’s blood State why it is important that sperm and egg cells are haploid and not diploid. State the function of the jelly coat that surrounds egg cells. Complete the sentences with the appropriate words. The placenta provides a large surface area for the of oxygen and carbon dioxide between maternal and fetal blood. Dissolved nutrients also pass across the placenta. Examples of dissolved nutrients are: acids, and . Antibodies pass from the maternal blood giving natural immunity to the baby for some infections that the mother has had or has been vaccinated against. Each different type of vaccine contains one or more taken from the that causes the disease.
0610_s22_qp_41
THEORY
2022
Paper 4, Variant 1
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Questions Discovered
229