Selective Breeding In Animals And Plants
Overview
Almost every animal and crop on a modern farm has been shaped by people. The dairy cow that gives thousands of litres of milk, the rice that shrugs off a disease that once destroyed harvests, the wheat with fat heads of grain: none of these arose by chance. They are the result of selective breeding, the patient choosing of the best parents generation after generation until a desired feature becomes the norm.
In this lesson you will learn how artificial selection improves yield, disease resistance, hardiness and appearance in livestock and crops, using real named breeds and varieties. You will see how artificial insemination spreads the genes of an outstanding sire across thousands of animals, weigh up its benefits and drawbacks, and learn the crucial difference between traditional selective breeding and producing genetically modified (GM) crops.
Objectives
- (a) describe how breeding can improve yield, disease resistance, hardiness and appearance in livestock and in crops.
- (b) understand the role of artificial selection in the production of improved varieties of animals and plants of economic importance.
- (c) understand the benefits of artificial insemination.
- (d) understand the differences between selective crop breeding and genetically modified (GM) crops.
Lesson Note
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Lesson Evaluation
Congratulations on completing the lesson on Selective Breeding In Animals And Plants. 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.
- Selective breeding improves a herd or crop by: A. Inserting genes from another species B. Breeding only from individuals with the desired feature C. Spraying chemicals on the best plants D. Giving extra fertiliser to the strongest animals Answer: B
- Which breed is famous for being selectively bred for very high milk yield? A. Holstein Friesian B. Merino C. Leghorn D. Aberdeen Angus Answer: A
- Artificial insemination is mainly used to: A. Cure diseases in cattle B. Spread the genes of one superior male to many females C. Increase the milk fat content directly D. Replace selective breeding completely Answer: B
- Which statement is true of a GM crop but not of a crop improved by selective breeding? A. It can pass features to its offspring B. It was developed by farmers C. It contains a gene inserted directly into its DNA D. It can increase yield Answer: C
- Which of these is a disadvantage of growing GM crops? A. They always have lower yields B. The seed is often expensive to buy C. They cannot resist pests D. They take many generations to develop Answer: B
Available on the Green Bridge App
Download the Green Bridge CBT app on your phone or computer to access full lesson notes, practice questions, and more.
Available on the Green Bridge App
Download the Green Bridge CBT app on your phone or computer to access full lesson notes, practice questions, and more.
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