Interest Approach

Approach 1:

Discuss the demand on farmers to produce enough food for the billions of people on Earth. Also discuss how the land available to farmers continues to decrease because of new buildings like subdivisions, malls, and the expansion of cities. Use an apple to demonstrate the small amount of land we have available for food production:

Interest Approach Continued

Approach 2:

Have students taste test apple, cereal, and tofu. After they have eaten, explain to them that these food products and many others are involved in biotechnology.

Student Learning Objectives. Instruction in this lesson should result in students achieving the following objectives:

1 Describe how biotechnology directly affects the lives of humans.

2 Explain how DNA influences the ways that people, animals, and plants grow.

3 Explain how biotechnology is applied in agriculture.

Terms. The following terms are presented in this lesson (shown in bold italics):

Biotechnology Bovine somatotropin (bST) Bt corn DNA Dominant gene Double helix Gene Genetic code Recessive gene

OBJECTIVE 1: Describe how biotechnology directly affects the lives of humans. Anticipated Problem: How does

biotechnology directly affect our lives?

I. Biotechnology: ‘Bio’ meaning biology or living things and ‘technology’ meaning tools. Biotechnology is a science that uses living things to make new products.

OBJECTIVE 1 continued

A. All living things have a blueprint that determines what that organism will look, act, and feel like, or the living thing’s traits.

1. This blueprint is a specific genetic code.

2. This genetic code determines what color a flower will be, what an apple will taste like, or what color a child’s eyes are.

OBJECTIVE 1 continued

B. Biotechnology can be used to help humans.

1. Biotechnology improves foods and crops by adding specific characteristics that give the plant new benefits. For example, biotech rice contains more iron than regular rice.

2. A specific gene is taken from one plant and placed into the DNA of a second plant. The second plant will then grow with all its own traits plus the one from the first plant.

OBJECTIVE 2: Explain how DNA influences the way people, animals, and plants grow.

Anticipated Problem: How does DNA influence the way organisms grow?

II. Since the discovery of DNA, scientists have studied how DNA relates to the growth of organisms.

OBJECTIVE 2 continued

A. Basic background of genes.

1. A gene determines what an organism’s offspring will look and feel like.

2. All living things have genes. Each organism has between 50,000 and 100,000 genes.

3. Genes are a part of a DNA molecule in a chromosome, which is found in a cell.

OBJECTIVE 2 continued

4. Human beings have two of every type of gene. One gene is received from the mother and the other from the father.

5. Genes can be dominant or recessive. Two dominant genes will allow the dominant characteristic to appear. Two recessive genes will cause the recessive trait to be displayed. If one dominant and one recessive gene are paired, the dominant gene will overpower the recessive gene and the characteristic of the dominant gene will appear in the offspring.

TT two dominant genes

tt two recessive genes

Tt one dominant gene and one recessive gene

OBJECTIVE 2 continued

6. The probability of a genetic outcome can be determined using a Punnet Square.

Plant 1: Tt

Plant 2: Tt

T

t

T t

TT

Tt

Tt

tt

OBJECTIVE 2 continued

B. DNA is made up of genes.

1. DNA (deoxyribonucleic acid) is the molecule in a chromosome that furnishes the genes with information for their development.

OBJECTIVE 2 continued

2. There are four different bases on a DNA molecule:a. Adenine (A)b. Thymine (T)c. Guanine (G)d. Cytosine (C)

OBJECTIVE 2 continued

3. These four bases form base pairs.a. Adenine joins with Thymine (A–T)b. Guanine joins with Cytosine (G–C)

4. A DNA strand is twisted in a double helix. A double helix is the spiral structure that DNA forms. The average length of a DNA strand is 6 feet long!

OBJECTIVE 3: Explain how biotechnology is applied in agriculture.

Anticipated Problem: How does biotechnology work in agriculture?

III. Biotechnology lets researchers take good traits from one organism and place them into another, creating a better organism. Biotechnology can be used to improve many agriculture products.

OBJECTIVE 3 continued

A. Milk

1. Through biotechnology, researchers have been able to increase the amount of milk a dairy cow can produce by increasing the amount of the bovine growth hormone, known as bovine somatotropin (bST), which is the hormone secreted by the pituitary gland that regulates milk secretion by the mammary glands of cows.

2. bST is a protein that increases the amount of energy cows put toward producing milk. In other words, bST redirects the energy cows get from feed from weight gain to milk production.

OBJECTIVE 3 continued

3. Cows naturally produce bST in their bodies but not in large amounts. Biotechnology has allowed researchers to put the gene that controls bST production into the DNA of a harmless bacteria.

4. This bacteria is then injected into the cow’s system, resulting in increased bST production and increased milk production.

OBJECTIVE 3 continued

5. Through the use of this

biotechnology, milk production

can be increased by 10 to 25 percent. 6. The milk causes no harmful side

effects in humans because bST is a natural hormone that has always been present in milk.

7. There are also no side effects for the cows.

OBJECTIVE 3 continued

B. Insecticides

1. Farmers use insecticides to fight damage to crops caused by insects. Insecticides are traditionally sprayed on the field to kill the harmful bugs.

2. Spraying can sometimes cause environmental problems, such as drifting and runoff into nearby streams.

OBJECTIVE 3 continued

3. Biotechnology researchers have taken genes from plants that naturally kill the insects that harm corn and placed these genes into the DNA of the corn. The result is Bt corn, a corn plant that can kill harmful bugs on its own without the use of spray insecticides. This technology has also been used in potatoes, cotton, and rice.

OBJECTIVE 3 continued

C. Golden rice

1. Golden rice was a huge breakthrough for the biotechnology industry. This rice contains increased amounts of beta-carotene and iron.

2. The beta-carotene is made into Vitamin A by the human body and prevents infection and blindness. More than 400 million people worldwide suffer from a Vitamin A deficiency.

OBJECTIVE 3 continued

3. Iron is needed to maintain the human body. People with an iron deficiency suffer from anemia. There are 3.7 billion people worldwide who do not get enough iron.

4. The creation of golden rice was especially important to people in developing countries who depend on rice as a dietary staple but who were not receiving enough nutrients. The introduction of this rice allowed them to grow rice that was full of needed nutrients.

5. The genes to create this rice came from a number of different sources, one of those being daffodils.

REVIEW

1. How does biotechnology directly affect our lives?

2. How does DNA influence the way organisms grow?

3. How does biotechnology work in agriculture?