Biology- Genetic Engineering and Cloning

Genetic Engineering- move genes from one organsim to another so it produces useful biological products.

ADVANTAGES

• You can produce organisms with new and useful features very quickly

DISADVANTAGES

• Inserted gene may have unexpected harmful effects
• Engineered DNA may 'escape'

1) First the gene that's responsible for producing the desirable charcteristic is selected

2) It's then 'cut' from the DNA using enzymes and then isolated

3) The useful gene is inserted into the DNA of another organsim

4) The organism replicates and soon loads of similar organisms all produce the same thing.

USES

• Vitamin A deficiency- gene that controls beta-carotene production in carrot plants is placed in rice plants and is then converted to Vitamin A.
• Human Insulin Production- been put into bacteria, has been cultured in a fementer and is simply extracted from the medium as they produce it.
• Cut out genes that make plants not resistance to things that could effect them

MORAL AND ETHICAL ISSUES INVOLVED:
1) People think it's wrong to genetically engineer other organisms purely for human benefit.

2) People worry that genetically engineering will carry on into the future and people who can afford it will have the characteristics they want their children to have modified

3) Evolutionary consequences are unknown.

Cloning is a type of asexual reproduction. It produces cells that are gentically identical to an original cell.

• Adult cell cloning involves an unfertilised egg cell with a removed haploid nucleus (the egg is enucleated)
• A nucleus is taken from a adult body cell (diploid nucleus-contains full number of chromosomes)
• The diploid nucleus is inserted into the 'empty' egg cell.
• The egg cell is then stimulated by an electric shock- this makes it divide by mitosis.
• When the embryo is a ball of cells, it's implanted into an adult female to grow into a gentically identical copy of the original body cell.

USES- helps with the shortage of organs for transplants. Human embryos could be produced by cloning adult body cells.

ISSUES- reduced gene pool, cloned mammals may not live as long, may have unhealthy immune systems.

Selective Breeding- humans artifically select plants or animals that we are going to breed and have their genes remain in the population.

BEST FEATURES IN SELCTIVE BREEIDNG

• Maximum yield of meat, milk, grain etc.
• Good health and disease resistance

Basic process

• Select existing stock with the best charcteristics and breed them with each other
• Select the best offspring and breed them together
• Continue this process over generations

MAIN PROBLEM
Reduces the gene pool in a population and reduces the number of different alleles. This makes less chance of any resistant alleles being present in the population.