cloning

Question 1

what is nuclear transfer?

Answer 1

this involves removing the nucleus from a body cell and placing it into an egg cell that has had its nuclues removed

Question 2

why are animals cloned?

Answer 2

mass produce animals with desirable characteristics
produce animals that have been genetically engineered to provide human products
produce human embryos to supply stem cells for thrapy

Question 3

name an ethical issue with cloning?

Answer 3

some people think it is wrong because they will not be a ‘true individual’

Question 4

explain the stages of cloning

Answer 4

the donor egg has its nucleus removed
the egg cell nucleus was replaced with the nucleus from an udder cell
the egg cell is given an electric shock to make it divide
the embryo is implanted into a surrogate mother
the embryo grows into a clone of the sheep from which the udder cell came

Question 5

name an advantage of cloning plants

Answer 5

growers can be sure of the characteristics of each plant since all the plants will be genetically identical

Question 6

name a disadvantage of cloning plants

Answer 6

if the plants become susceptible to disease or to change in the environmental conditions, then all the plants will be affected

Question 7

what is the name of the process which makes plants able to be cloned?

Answer 7

tissue culture

Question 8

explain the stages of tissue culture

Answer 8

a plant is selected that has certain characteristics
a large number of small pieces of tissue are then cut from the plant
the small pieces of tissue are grown in test tubes or dishes containing a growth medium
aseptic technique is used at all stages to stop and microbes infecting the plants

Question 9

why is it easier to clone plants than animals?

Answer 9

because many plant cells retain the ability to differentiate