Question 1

Q1: Asexual reproduction takes place through budding in (a) Amoeba. (b) Yeast. (c) Plasmodium. (d) Leishmania.

Accepted Answer

(b) Yeast. Explanation: Amoeba and Leishmania reproduce by binary fission. Plasmodium reproduces by multiple fission. Yeast reproduces asexually by putting out small buds that separate and grow into new individuals.

Question 2

Q10: How does reproduction help in providing stability to populations of species?

Accepted Answer

Reproduction is crucial for providing stability to populations of species in the following ways: 1.  Continuity of Population: Reproduction is the process by which new individuals are created, replacing older individuals that die. This ensures the continuity of the population from one generation to...

Question 3

Q11: What could be the reasons for adopting contraceptive methods?

Accepted Answer

People may adopt contraceptive methods for several personal, health, and social reasons: 1.  To Prevent Unwanted Pregnancy: This is the primary reason. It allows individuals and couples to choose if and when they want to have children. 2.  Family Planning and Spacing: Contraceptive methods help in p...

Question 4

Q2: Which of the following is not a part of the female reproductive system in human beings? (a) Ovary (b) Uterus (c) Vas deferens (d) Fallopian tube

Accepted Answer

(c) Vas deferens Explanation: The vas deferens is a part of the male reproductive system. It is the tube that transports sperms from the testes. The ovary, uterus, and fallopian tube are all parts of the female reproductive system.

Question 5

Q3: The anther contains (a) sepals. (b) ovules. (c) pistil. (d) pollen grains.

Accepted Answer

(d) pollen grains. Explanation: The anther is part of the stamen, which is the male reproductive part of a flower. The anther's function is to produce and store pollen grains, which contain the male germ-cells.

Question 6

Q4: What are the advantages of sexual reproduction over asexual reproduction?

Accepted Answer

Sexual reproduction has several key advantages over asexual reproduction, primarily related to genetic variation: 1.  Generation of Variation: Sexual reproduction involves combining DNA from two different individuals. This creates new combinations of genes and variations in the offspring. Asexual re...

Question 7

Q5: What are the functions performed by the testis in human beings?

Accepted Answer

The testes (singular: testis) are the primary reproductive organs in males and perform two main functions: 1.  Sperm Production: The primary function of the testes is the formation and maturation of male germ-cells, called sperms. This process is known as spermatogenesis. Sperm formation requires a...

Question 8

Q6: Why does menstruation occur?

Accepted Answer

Menstruation occurs as part of the monthly reproductive cycle in females when the egg released by the ovary is not fertilised. Each month, the uterus prepares itself to receive a fertilised egg. Its inner lining (endometrium) becomes thick, soft, and richly supplied with blood vessels to nourish a p...

Question 9

Q7: Draw a labelled diagram of the longitudinal section of a flower.

Accepted Answer

To draw a labelled diagram of the longitudinal section of a flower, you should include and label the following parts, as shown in Figure 7.7 of the textbook: 1.  Pedicel: The stalk of the flower. 2.  Receptacle: The part of the flower stalk where the parts of the flower are attached. 3.  Sepals: The...

Question 10

Q8: What are the different methods of contraception?

Accepted Answer

Contraceptive methods are ways to avoid pregnancy and can be categorised as follows: 1.  Mechanical/Barrier Methods: These methods physically prevent sperm from reaching the egg.        Condoms: A covering worn over the penis or inside the vagina. They also help prevent the transmission of sexually...

Question 11

Q9: How are the modes for reproduction different in unicellular and multicellular organisms?

Accepted Answer

The modes of reproduction in unicellular and multicellular organisms differ significantly due to the complexity of their body designs.    Unicellular Organisms: These organisms have a simple body structure consisting of a single cell. Reproduction is typically asexual and involves the division of th...

Question 12

Q1: How is the process of pollination different from fertilisation?

Accepted Answer

Question 13

Q2: What is the role of the seminal vesicles and the prostate gland?

Accepted Answer

The seminal vesicles and the prostate gland are accessory glands in the male reproductive system. Their role is to add their secretions to the sperms as they pass through the vas deferens. This fluid serves two main purposes: 1.  Provides a Medium for Transport: The secretions form a fluid medium (s...

Question 14

Q3: What are the changes seen in girls at the time of puberty?

Accepted Answer

The changes seen in girls at the time of puberty are part of their sexual maturation. These include:    Increase in breast size, with the darkening of the skin of the nipples.    Growth of hair in new parts of the body, such as the armpits and the genital area.    The onset of menstruation (the mont...

Question 15

Q4: How does the embryo get nourishment inside the mother's body?

Accepted Answer

The embryo gets nourishment inside the mother's body through a special tissue called the placenta. The placenta is a disc-like structure embedded in the uterine wall. It is connected to the embryo via the umbilical cord. On the embryo's side of the placenta, there are villi which create a large surf...

Question 16

Q5: If a woman is using a copper-T, will it help in protecting her from sexually transmitted diseases?

Accepted Answer

No, a copper-T will not help in protecting a woman from sexually transmitted diseases (STDs). The copper-T is an intrauterine contraceptive device (IUCD) placed inside the uterus to prevent pregnancy. It works by preventing the implantation of the embryo. It does not create a physical barrier to pre...

Question 17

Q1: What is the importance of DNA copying in reproduction?

Accepted Answer

DNA copying is of fundamental importance in reproduction for the following reasons: 1.  Inheritance of Traits: The DNA in the cell nucleus contains the genetic information for the inheritance of features from parents to the next generation. DNA copying ensures that this information, which acts as a...

Question 18

Q2: Why is variation beneficial to the species but not necessarily for the individual?

Accepted Answer

Variation is beneficial to a species for its long-term survival, but it may not always benefit an individual organism.    Benefit to the Species: Variations within a population mean that some individuals might have traits that allow them to survive drastic environmental changes (like a sudden increa...

Question 19

Q1: How does binary fission differ from multiple fission?

Accepted Answer

Question 20

Q2: How will an organism be benefited if it reproduces through spores?

Accepted Answer

An organism that reproduces through spores benefits in two main ways: 1.  Survival in Unfavourable Conditions: Spores are covered by thick, protective walls. This allows them to withstand harsh environmental conditions such as high temperatures, lack of moisture, and scarcity of food. They can remai...

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