6.1.3 (g-h)

Question 1

How has insecticide been implemented in soya beans?

Answer 1

• A gene has been inserted into soya beans, so they produce a Bt protein, which is toxic to pest insects – so it is a pesticide
  
  • Meaning there is no need to spray insecticide that can harm non-pest insects
• Another gene has been inserted, which is resistant to common weed killers, so weed killers can be sprayed and the crop won’t be affected
• This all increases yield

Question 3

What are the disadvantages to insect resistance?

Answer 3

• Non-pest insects maybe damaged by Bt protein toxin in plants
• Insect pests may develop resistance
• Insect-eating predators may have their food chain affected, or they are affected when they consume insects that have eaten the toxins

Question 4

What is pharming and its ethical issues?

Answer 4

The use of GM animals to produce pharmaceuticals

2 Aspects:

1. Creating Animal Models
   
   1. The addition or removal of genes so animals develop certain diseases, which can be used as models for new therapies
2. Creating Human Proteins:
   
   1. Introducing a human gene that codes for medically required proteins
      
      1. Sometimes animals are used as bacteria can’t produce complex eukaryotic proteins
   2. The human gene will be introduced into the genetic material of an animal, e.g. cow egg, the transgenic embryo will be grown a foal, the milk of the foal will have the desired protein that can be harvested

Ethical Issues

• Farm animals will suffer pain, or metabolism issues

Question 5

What issues revolve about patenting and technology transfer?

Answer 5

• ### Farmers in developing countries will be prevented from using GM crop/products
• Because commercial companies looking to make profits will patent their technology and information
• The commercial companies will not want to share this information
• Poorer farmers will not be able to afford these GM products as they are too expensive

Question 6

What is the use of GM pathogens?

Answer 6

Pathogens such as viruses can be modified to carry genes into animal DNA to bring about disease resistance, or to modify farm animal physiology

However, the viruses used as vectors may increase risk of disease or cancer if not controlled or properly modified

Question 7

What is gene therapy and the 2 types?

Answer 7

Gene Therapy: Treating genetic disorders by inserting new alleles, not replacing genes

• Somatic cell gene therapy
• Germ line cell gene therapy

Question 8

What is somatic cell gene therapy?

Answer 8

• Involved replacing mutant alleles with healthy alleles in the affected cells
  
  • The genes can produce proteins allowing the cells to be killed as they produce foreign antigens, so attacked by own immune system
• Somatic cell gene therapy is short term and only affects the individual, the healthy allele is passed on each time the cell divides, but when the cell dies, and new cells form from stem cells, the mutant allele is back
• The offspring will not be protected from the genetic disorder

Question 9

What is germ line cell gene therapy?

Answer 9

• Involves inserting a healthy allele into a zygote/embryo
• The individual will be born health with the normal allele