New genes for old

Question 1

What are the possible problems with selective breeding?

Answer 1

They can lead to inbreeding where two closely related individuals mate, and this can cause health problems within the species. Certain breeds of dog show these problems

Question 2

Inbreeding can reduce the variety alleles in the population (the gene pool). This can lead to:

Answer 2

• An increased risk of harmful recessive characteristics shown up in offspring.
• A reduction in a variation, so that populations cannot adapt to change so easily.

Question 3

Genetic engineering has advantages and risks:

Answer 3

• One advantage is that organisms with desired features can be produced very quickly.
• However, there is a risk that the inserted genes may have unexpected harmful side effects.

Question 4

Examples of organisms that have been made using genetic engineering include the following:

Answer 4

• Rice that contains beta-carotene has been made by inserting the genes that control beta-carotene production from carrots. Humans can then convert the beta-carotene for my son to vitamin A. This is important because in some parts of the world rely on rice, which normally has very little Vitamin A.
• Genetically engineered bacteria has been made that produce human insulin.
• Crop plants have been made that are resistant to herbicides, frost damage or disease.

Question 5

A number of ethical issues are involved in genetic engineering:

Answer 5

• Some people are worried about possible long-term side effects, e.g. that genetically engineered plants or animals will disturb natural ecosystems.
• Other people think that it is wrong, whatever the intended effects.

Question 6

To carry out genetic engineering, four steps are taken;

Answer 6

1. The desired characteristics are selected.
2. The genes responsible are identified and removed (isloation).
3. The genes are inserted into other organisms.
4. The organisms are allowed to reproduce (replication).

Question 7

What is genetic therapy?

Answer 7

The process of using genetic engineering to change a person’s genes and cure certain disorders is called gene therapy.

Question 8

Controversy of gene therapy

Answer 8

Gene therapy involve body cells or gametes. Changing the genes in gametes is much more controversial. This is because it is sometimes difficult to decide which genes parents should be allowed to change. It could lead to’designer babies’.