Animal, Plant & Soil Science

1. Animal, Plant & Soil Science Lesson B2-5 Improving Agricultural Plants and Animals

2. Interest Approach • Approach One: Bring several newspaper articles about biotechnology to class. Read the main points to students, or have them read copies of the articles. Ask students questions concerning the articles, such as: Why is so much attention being given to biotechnology? What does biotechnology involve? Is biotechnology new to human civilization?

3. Interest Approach • Approach Two: Bring to class samples of foods that have been produced through biotechnology. Examples are bread, cheese, and the Flavr-Savr Tomato. Offer the opportunity for students to taste the foods. Follow up the sampling by asking if they noticed anything special about the foods. Direct the class discussion toward the lesson objectives.

4. Objectives • Discuss the importance of improved organisms in agriculture. • Identify methods used in agriscience to improve organisms. • Define biotechnology and examine its use in the past and its capabilities for the present and future. • Compare and contrast organismic and molecular biotechnology.

5. Terms • inbreeding • molecular biotechnology • organismic biotechnology • selection • selective breeding • urbanization • biotechnology • controlled breeding • gene splicing • genetic manipulation • hybridization • improvement by selection

6. Why are improved organisms important in agriculture? • Scientists are continuously searching for improved organisms. • A common goal for all those involved in the agriculture industry is to find ways to produce more products by using fewer resources, such as land, labor, feed, and seed. • A. There are three main factors driving this goal.

7. Why are improved organisms important in agriculture? • 1. Rising world population— This is especially important as the world’s population continues to rise. • As life expectancy continues to rise and infant mortality rates continue to drop, more people are living longer. • All these people need to eat. • It is the job of agriculture to make sure there is enough food produced.

8. Why are improved organisms important in agriculture? • 2. Urbanization—Urbanization is the process in which more members of a population work and live in urban areas. • As the world’s population increases, people need places to live, work, and play. • The world’s cities continue to grow, swallowing up more and more land that was used for farming. • Because of this, producers are expected to produce more food using less land.

9. Why are improved organisms important in agriculture? • 3. Fewer people in production agriculture—In addition to these other problems faced by agriculture in feeding the world, there is a trend in which fewer people are becoming involved in production agriculture. • Because of this, the burden of feeding the world is placed on fewer and fewer people. • Also, the average age of the producer is very high.

10. Why are improved organisms important in agriculture? • B. One example of a major breakthrough in organism improvement occurred in the 1930s with the development of hybrid seed. • 1. Hybrids produce 25 to 50 percent greater yields than traditional corn varieties and are fairly tolerant of varying soil and climatic conditions.

11. Why are improved organisms important in agriculture? • 2. Another example of organism improvement can be found in the animal industry. • Today, cattle and hogs can reach market weight several days sooner using less feed. • This allows for the producer to raise more animals in a shorter period of time with fewer inputs.

12. What are some methods used in agriscience to improve organisms? • It has been, and always will be, the goal of agriculturists to improve the animals and plants around us. • Two major approaches are used: controlled breeding and genetic manipulation. • A. Controlled breeding is breeding plants or animals to achieve certain characteristics in the offspring. • This is considered a natural method of improving plants and animals. In this method, scientists control the natural breeding process. • There are three kinds of controlled breeding: selection, inbreeding, and hybridization.

13. What are some methods used in agriscience to improve organisms? • 1. Selection involves choosing a few parents with the desired traits with the intent of increasing the amount of desired qualities in the offspring. • 2. Inbreeding involves breeding offspring of the same parents to each other. • This is done in both plants and animals; however, it is done somewhat differently in plants than animals. • The purpose of this method is to produce a new generation without the introduction of any new genes.

14. What are some methods used in agriscience to improve organisms? • 3. Hybridization involves the crossing of two different plants or animals to produce desired traits in offspring. • This method combines the traits of different parent strains. • Many hybrids are not able to reproduce.

15. What are some methods used in agriscience to improve organisms? • B. Genetic manipulation is an artificial means of producing desirable traits. • Genes can be moved from one species to another. • Gene splicing is the moving of hereditary characteristics from one organism to another, often unrelated organism.

16. What is biotechnology? What was its use in the past, and what are its capabilities for the present and future? • Biotechnology involves applying technology to living organisms to improve existing products or make new ones. • The agriscientist’s broader view of biotechnology applies to operations involving plants and animals to produce food, fiber, and shelter. • A. Biotechnology has been used by people for centuries.

17. What is biotechnology? What was its use in the past, and what are its capabilities for the present and future? • 1. Yeast used for bread and bacteria used in fermentation and cheese production were some of the first applications of biotechnology. • 2. Improvement by selection was an early method to choose and keep the best plants and animals for further use.

18. What is biotechnology? What was its use in the past, and what are its capabilities for the present and future? • 3. Hybridization is another example of biotechnology. • In crops, hybridization involves the controlled pollination of plants and was practiced as people replanted seed from their best plants in the next growing season. • 4. Breeding livestock to obtain desired characteristics in the offspring is known as selective breeding.

19. What is biotechnology? What was its use in the past, and what are its capabilities for the present and future? • B. Plants, animals, and microbes can be improved by modifying the genetic content of cells.

20. How do the areas of organismic and molecular biotechnology differ? • Biotechnology has two main areas of application: one that deals with the entire organism and another that involves work with individual cells. • A. Organismic biotechnology involves practices that promote more healthy and productive organisms. • B. The area of biotechnology that involves changing an organism at the cellular level is referred to as molecular biotechnology.

22. Review • Why are improved organisms important in agriculture? • What are some methods used in agriscience to improve organisms?

23. Review • What is biotechnology? What was its use in the past, and what are its capabilities for the present and future? • How do the areas of organismic and molecular biotechnology differ?