Question 1 · MCQ · Analyse · 1 mark
Multiplying a useful rose variety
Asexual reproduction
A gardener wants many rose plants that retain the features of a selected parent. Which method is most suitable?
(A) Cross-pollinating unrelated rose plants
(B) Growing every plant from sexually produced seeds
(C) Using stem cuttings from the selected plant
(D) Mixing pollen from many varieties
Show answer and solution
Answer: (C) Using stem cuttings from the selected plant
Worked solution: Vegetative propagation through cuttings produces plants genetically very similar to the selected parent, apart from possible mutations. Sexual reproduction produces new combinations of traits.
Question 2 · MCQ · Analyse · 1 mark
Pollen reaches a stigma
Sexual reproduction in plants
Pollen is transferred from the anther to a receptive stigma. Which event has occurred?
(A) Pollination
(B) Fertilisation of the egg
(C) Germination of the seed
(D) Formation of a fruit from a seed
Show answer and solution
Answer: (A) Pollination
Worked solution: Pollination is pollen transfer to a stigma. Fertilisation happens later when a male gamete fuses with the egg.
Question 3 · MCQ · Analyse · 1 mark
Variation among offspring
Reproduction and variation
Why do sexually produced offspring generally show more combinations of inherited traits than offspring produced by simple binary fission?
(A) Sexual reproduction copies no DNA.
(B) Sexual reproduction combines genetic material from two parents.
(C) Binary fission always destroys all genes.
(D) Every sexually produced offspring has the same genotype.
Show answer and solution
Answer: (B) Sexual reproduction combines genetic material from two parents.
Worked solution: Sexual reproduction brings genetic contributions from two parents together. Binary fission chiefly copies the genetic material of one parent, with variation mainly arising from copying changes.
Question 4 · MCQ · Analyse · 1 mark
The usual site of fertilisation
Human reproduction
In the human female reproductive system, where does fertilisation normally occur?
(A) Urinary bladder
(B) Vagina
(C) Uterus lining
(D) Oviduct (fallopian tube)
Show answer and solution
Answer: (D) Oviduct (fallopian tube)
Worked solution: Sperm and egg normally fuse in an oviduct. The developing embryo then travels towards the uterus for implantation.
Question 5 · A-R · Analyse · 1 mark
DNA copying and differences
Reproduction and variation
Assertion (A): Offspring produced asexually can occasionally show small inherited differences from the parent.
Reason (R): DNA copying is not perfectly error-free.
(a) Both A and R are true, and R correctly explains A.
(b) Both A and R are true, but R does not correctly explain A.
(c) A is true, but R is false.
(d) A is false, but R is true.
Show answer and solution
Answer: (A) Both A and R are true, and R correctly explains A.
Worked solution: Copying changes can introduce genetic variation even when only one parent contributes DNA. Asexual reproduction usually gives close similarity, not guaranteed absolute identity.
Question 6 · A-R · Analyse · 1 mark
What contraceptive pills do not provide
Reproductive health
Assertion (A): Oral contraceptive pills protect against HIV transmission in the same way as a barrier condom.
Reason (R): Oral contraceptive pills act hormonally and do not form a physical barrier to pathogen transmission.
(a) Both A and R are true, and R correctly explains A.
(b) Both A and R are true, but R does not correctly explain A.
(c) A is true, but R is false.
(d) A is false, but R is true.
Show answer and solution
Answer: (D) A is false, but R is true.
Worked solution: Hormonal contraception does not provide the barrier protection against sexually transmitted infections that a correctly used condom can help provide.
Question 7 · VSA · Apply · 2 marks
A bud on yeast
Asexual reproduction
A small outgrowth develops on a yeast cell, grows and separates. Name the method and explain how the daughter cell receives genetic material.
Show answer and solution
Answer: Budding; the nucleus divides and one daughter nucleus enters the bud.
Worked solution: The outgrowth enlarges as a nucleus produced by division moves into it. The bud develops into a new cell and can detach from the parent.
Question 8 · VSA · Apply · 2 marks
A structure linking embryo and mother
Human reproduction
Name the structure that allows exchange of nutrients, gases and wastes between the mother and developing embryo, without requiring their blood to mix directly.
Show answer and solution
Answer: Placenta.
Worked solution: The placenta provides a large exchange surface between maternal tissues and embryonic tissues. Nutrients and oxygen move towards the embryo, while carbon dioxide and other wastes move towards the mother.
Question 9 · SA · Analyse · 3 marks
Following a pollen grain
Sexual reproduction in plants
A compatible pollen grain lands on a stigma. Describe the sequence leading to fertilisation and state what the ovule and ovary usually become afterwards.
Show answer and solution
Answer: A pollen tube carries male gametes towards the ovule; a male gamete fuses with the egg. The ovule becomes a seed and the ovary becomes a fruit.
Worked solution: The pollen grain germinates and a tube grows through the style. The male gamete reaches the embryo sac and fuses with the egg to form a zygote. The zygote develops into an embryo, the ovule becomes a seed and the ovary usually develops into a fruit.
Question 10 · SA · Analyse · 3 marks
Comparing two contraceptive approaches
Reproductive health
Compare a condom and a surgical method such as vasectomy in terms of their main mechanism and protection against sexually transmitted infections.
Show answer and solution
Answer: A condom acts as a barrier and can reduce STI transmission; vasectomy blocks sperm transport and does not provide STI protection.
Worked solution: A correctly used condom reduces the passage of sperm and direct exposure to sexual fluids. Vasectomy interrupts the sperm ducts so sperm are not carried into semen. Preventing sperm transport does not create a barrier against pathogens, so it does not itself protect against STIs.
Question 11 · LA · Analyse · 5 marks
Two ways of producing new plants
Asexual and sexual reproduction
A farmer grows potato from tuber buds and a breeder grows pea plants from seeds after cross-pollination. Compare the processes using (i) number of genetic parents, (ii) gamete fusion, (iii) expected similarity, (iv) speed or preservation of useful traits, and (v) a benefit of variation.
Show answer and solution
Answer: Potato propagation is vegetative and asexual; cross-pollinated peas are produced sexually. Sexual reproduction generates more trait combinations.
Worked solution: A tuber bud grows from one parent without gamete fusion and usually preserves the parent’s genetic features, allowing rapid multiplication of a useful variety. A cross-pollinated pea seed receives genes from two parent plants after fertilisation. Their combinations can produce varied offspring. Variation can help some individuals survive environmental changes, although it does not guarantee that every offspring is better adapted.
Question 12 · Case Study · Analyse · 4 marks
Preventing accidental pollen transfer
Sexual reproduction in plants
A breeder removes the anthers from an unopened bisexual flower before pollen is released, covers the flower with a bag, and later applies pollen from a chosen plant of the same species. The flower is covered again.
Answer the following:
(i) Why are the anthers removed? [1 mark]
(ii) Why is the flower covered? [1 mark]
(iii) Distinguish the pollen transfer from the gamete fusion that can follow. [2 marks]
Show answer and solution
Answer: (i) To prevent self-pollination from its own anthers. (ii) To exclude unwanted pollen. (iii) Transfer to the stigma is pollination; fusion of a male gamete with the egg is fertilisation.
Worked solution: Removing anthers before they release pollen helps control the source of pollen. Bagging prevents accidental pollination. The selected pollen must still germinate and deliver a male gamete to the egg; pollen transfer alone is not fertilisation.
