Sexual Reproduction
Overview
No two brothers or sisters are exactly alike, even with the same parents. That variety is the hallmark of sexual reproduction, where two special cells from two parents join and mix their genes to make a unique new individual.
In this lesson you will learn what sexual reproduction is, what fertilisation means, and (for the extended curriculum) how gametes are haploid while the zygote they form is diploid. You will also weigh up the advantages and disadvantages of producing varied offspring, both in the wild and in crop production.
Objectives
- Describe sexual reproduction as a process involving the fusion of the nuclei of two gametes to form a zygote and the production of offspring that are genetically different from each other
- Describe fertilisation as the fusion of the nuclei of gametes
- [Supplement] State that nuclei of gametes are haploid and that the nucleus of a zygote is diploid
- [Supplement] Discuss the advantages and disadvantages of sexual reproduction: (a) to a population of a species in the wild (b) to crop production
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Lesson Evaluation
Congratulations on completing the lesson on Sexual Reproduction. Now that youve explored the key concepts and ideas, its time to put your knowledge to the test. This section offers a variety of practice questions designed to reinforce your understanding and help you gauge your grasp of the material.
You will encounter a mix of question types, including multiple-choice questions, short answer questions, and essay questions. Each question is thoughtfully crafted to assess different aspects of your knowledge and critical thinking skills.
Use this evaluation section as an opportunity to reinforce your understanding of the topic and to identify any areas where you may need additional study. Don't be discouraged by any challenges you encounter; instead, view them as opportunities for growth and improvement.
- Sexual reproduction involves the fusion of the nuclei of: A. two body cells B. two gametes C. one gamete and one body cell D. two zygotes Answer: B
- Fertilisation is defined as the: A. division of a body cell B. fusion of the nuclei of gametes C. growth of a zygote D. production of spores Answer: B
- The nucleus of a gamete is: A. diploid B. haploid C. has no chromosomes D. has double the chromosomes Answer: B
- A zygote is formed when two gametes fuse. The zygote nucleus is: A. haploid B. diploid C. has no nucleus D. identical to one parent Answer: B
- An advantage of sexual reproduction is that the offspring show: A. no variation B. variation C. identical genes D. fewer chromosomes than the parents Answer: B
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