Cloning Flashcards
Name the two ways plants can be cloned
- From cuttings
- By tissue culture
Name the 2 ways you can clone animals
- Using embryo transplants
- Adult cell cloning
Explain how a plant can be cloned from cuttings
(3)
- A gardener takes some cuttings from a good parent plant
- The cuttings are kept in moist conditions until they are ready to be planted
- The cuttings are then planted to produce genetically identical copies of the parent plant
Name the 2 pros of cloning plants from cuttings
- Clones can be produced quickly
- Clones can be produced cheaply
Explain how plants can be cloned using a tissue culture
(2)
- A few plant cells are put in a growth medium with hormones
- They grow into new plants which are clones of the parent plant
Name 3 pros of using tissue cultures to clone plants
- Can be done quickly
- Can be done in very little space
- Can be grown all year
What do you use to make animal clones?
Embryo transplants
Explain how embryo transplants can be used by farmers to produce cloned offspring of their best cow and bull
(4 steps)
- Sperm cells are collected from the prize bull, and egg cells are collected from the prize cow.
- The sperm are then used to artificially fertilise an egg cell.
- The embryo that develops is then split many times (to form clones) before any cells become specialised
- These cloned embryos can then be implanted into lots of other cows where they will grow into genetically identical baby calves
What is the advantage of using embryo transplants in animals the way I have explained?
Hundreds of ‘ideal’ offspring can be produced every year from the best bull and cow
Describe the steps to adult cell cloning
- You take an unfertilised egg cell and remove its nucleus
- You insert a complete set of chromosomes from an adult body cell into the ‘empty’ egg cell
- Then stimulate the egg using an electric shock to make it divide like a normal embryo
- When the embryo is a ball of cells, implant it into a surrogate mother
- The embryo will now grow into an identical copy of the original adult body cell
Name the first animal successfully created using adult cell cloning
Dolly the sheep
Name 3 arguments for cloning
- You quickly get lots of ‘ideal’ offspring
- Studying cloned animals could lead to a greater understanding of the development of the embryo, and of ageing and age-related disorders
- Could be use to preserve endangered species
Name 3 arguments that oppose cloning
- You get a ‘reduced gene pool’
- Cloned animals might not be as healthy as non-cloned ones
- Human cloning might happen, which could result in failed attempts e.g. babies born severely disabled
Explain why a ‘reduced gene pool’ is bad
There are fewer alleles in a population.
If a population are closely related and a new disease appears, they could all be wiped out, as there may be no allele in the population giving resistance to the disease
What evidence is there to suggest that cloned animals might no be as healthy as non-cloned ones?
Is it sound?
Dolly the sheep had arthritis, which tends to occur in older sheep.
BUT we’re not sure whether that was caused by the cloning or some other factor