Reproduction in Organisms Quiz

Which of the following statements best explains why external fertilisation in animals requires a moist environment?

1. It ensures that fertilised eggs are easily dispersed.
2. It prevents the gametes from drying out and dying.
3. Moist environments increase the number of gametes produced.
4. It allows direct fertilisation without mating.

Answer: (b) It prevents the gametes from drying out and dying.

Match the reproductive adaptations in Column I with their advantages in Column II. Column I Column II P. Dioecious plants 1. Promotes cross-pollination Q. Self-incompatibility 2. Prevents self-fertilisation R. Monoecious plants 3. Allows self-pollination when necessary S. Cleistogamous flowers 4. Ensures seed production without pollinators

1. P-2, Q-3, R-1, S-4
2. P-3, Q-4, R-1, S-2
3. P-2, Q-1, R-4, S-3
4. P-1, Q-2, R-3, S-4

Answer: (d) P-1, Q-2, R-3, S-4

Which of the following statements regarding human reproduction are correct? 1. Fertilisation generally occurs in the fallopian tube (oviduct). 2. The blastocyst implants in the endometrium of the uterus. 3. The menstrual cycle is controlled by hormones like FSH and LH. 4. Spermatogenesis begins at puberty and continues throughout life.

1. All statements are correct
2. Statements 1, 2, and 3 are correct
3. Statements 1, 2, and 4 are correct
4. Statements 2, 3, and 4 are correct

Answer: (a) All statements are correct

A diagram of the male human reproductive system is shown below. If the vas deferens is blocked, which process will most likely be affected?

1. Spermatogenesis
2. Hormone secretion
3. Transportation of sperm
4. Fertilisation of the egg

Answer: (c) Transportation of sperm

Match the following reproductive strategies in Column I with their adaptive significance in Column II and environmental examples in Column III. Column I Column II Column III P. Parthenogenesis 1 High survival rate of zygotes A. Aphids Q. Internal fertilisation 2 Rapid population growth B. Amphibians R. External fertilisation 3 Requires water medium C. Humans

1. P-3-C, Q-2-A, R-1-B
2. P-2-B, Q-1-C, R-3-A
3. P-2-A, Q-1-C, R-3-B
4. P-1-C, Q-3-A, R-2-B

Answer: (c) P-2-A, Q-1-C, R-3-B

Which of the following statements correctly explains the role of pollinators in plant reproduction? 1. Pollinators facilitate cross-pollination. 2. Pollinators are essential only for self-pollinating plants. 3. Pollinators increase the chances of genetic variation. 4. Pollinators transfer nutrients from one flower to another.

1. 1 and 3 only
2. 2 and 4 only
3. 1, 2, and 3 only
4. All of the above

Answer: (a) 1 and 3 only

A student injects a chemical inhibitor that prevents the fusion of sperm cells with female gametes in the ovule. Which of the following outcomes is most likely to be observed?

1. The embryo forms, but the endosperm does not develop.
2. Both the embryo and endosperm develop normally.
3. The endosperm forms, but the embryo does not develop.
4. Neither the embryo nor the endosperm develops.

Answer: (d) Neither the embryo nor the endosperm develops.

Fertilisation in flowering plants occurs inside the ovule, where one sperm cell fuses with the egg cell and another sperm cell fuses with two polar nuclei. This unique process is known as double fertilisation, and it ensures the development of both the embryo and the nutrient-rich tissue that supports it. What is the primary significance of double fertilisation in flowering plants?

1. Formation of a protective seed coat.
2. Simultaneous formation of zygote and endosperm.
3. Prevention of genetic mutations during fertilisation.
4. Elimination of the need for pollination.

Answer: (b) Simultaneous formation of zygote and endosperm.

A plant species is observed to produce fruits without fertilisation. Which of the following processes could explain this phenomenon?

1. Gametogenesis
2. Apomixis
3. Parthenocarpy
4. Double fertilisation

Answer: (c) Parthenocarpy

During in vitro fertilization (IVF), a fertilized egg is incubated until at least eight cells are formed. Once the embryo reaches this stage, it is transferred to a specific location in the reproductive system to continue development. Which letter in the diagram indicates the correct location where the ball of cells would be transferred?

1. A
2. B
3. C
4. D

Answer: (b) B