Chapter 7: How do Organisms Reproduce?

Science • Class 10

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Chapter Analysis

Intermediate14 pages • English

Quick Summary

This chapter explores the various modes of reproduction in organisms. It discusses the importance of DNA copying in reproduction and how it leads to variation within a species, which is crucial for survival. The chapter covers both asexual and sexual reproduction, highlighting methods such as fission, budding, vegetative propagation, and the biological intricacies of sexual reproduction in plants and humans. It also examines human reproductive health and the significance of contraception.

Key Topics

  • Asexual Reproduction
  • DNA Copying and Variation
  • Modes of Reproduction
  • Sexual Reproduction in Plants
  • Human Reproductive Systems
  • Reproductive Health
  • Contraception
  • Importance of Variation

Learning Objectives

  • Understand the different modes of reproduction in organisms
  • Describe the process of DNA copying and its significance
  • Identify the reproductive parts of flowering plants and their functions
  • Explain the human reproductive system and associated physiological processes
  • Discuss the importance of reproductive health and contraception
  • Appreciate the role of variation in species survival and evolution

Questions in Chapter

What is the importance of DNA copying in reproduction?

Answer: DNA copying is crucial as it ensures that genetic information is passed on to the next generation with some degree of variation, enhancing survival through evolution.

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

Answer: Variation among species increases the chances of survival in changing environments, whereas individuals with variations might not always have a survival advantage.

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How is the process of pollination different from fertilisation?

Answer: Pollination involves the transfer of pollen from the anther to the stigma, while fertilisation is the fusion of male and female gametes.

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

Answer: They contribute fluids that provide nutrition and facilitate the movement of sperm.

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

Answer: Changes include enlargement of breasts, growth of pubic hair, and onset of menstruation.

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How does the embryo get nourishment inside the mother’s body?

Answer: The embryo receives nourishment through the placenta, which facilitates the exchange of nutrients and wastes between the mother and the embryo.

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

Answer: No, the copper-T is a contraceptive device that does not prevent sexually transmitted diseases.

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Additional Practice Questions

What are the advantages of asexual reproduction?

medium

Answer: Asexual reproduction allows for rapid and large-scale reproduction without the need for a mate, which is advantageous in stable, unchanging environments.

Explain how vegetative propagation can be beneficial in agriculture.

easy

Answer: Vegetative propagation allows plants to reproduce quickly and maintain desired traits, as the offspring are genetically identical to the parent. It is often used to cultivate crops like potatoes and sugarcane.

Describe the role of meiosis in sexual reproduction.

hard

Answer: Meiosis is a type of cell division that reduces the chromosome number by half, producing gametes (sperm and egg cells), and leads to genetic variation through recombination of genetic material.

What physiological changes occur during puberty?

medium

Answer: During puberty, individuals experience growth spurts, development of secondary sexual characteristics, and changes in body composition and distribution of body fat.

How do contraceptive methods help in family planning?

easy

Answer: Contraceptive methods help in controlling population growth, spacing children, and enabling individuals and couples to plan the size of their families while avoiding unintended pregnancies.

NCERT Exemplar

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Practice with NCERT Exemplar problems and solutions for this chapter. Exemplar problems are designed to help you master the concepts with advanced-level questions.

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