A clone is a copy of animals and plants. They are genetically identically. They all have the same DNA as the original animal or plant.
What does cloning involve?
Involves only one parent. It is an example of asexual reproduction.
Give an example of a natural clone?
Identical twins are natural clones.
How was the Dolly the sheep cloned?
Using the DNA in the nucleus of udder cells. This process is called nuclear transfer. It involved taking a body cell from a sheep, removing the nucleus and transferring it to an egg cell.
What is the importance of cloning?
Cloning could result in large numbers of animals with the right characteristics, such as cows that could live in drought conditions but still provide plenty of milk.
What is the advantage of cloning pigs?
To supply organs for transplants into humans.
What can cloned embryos do?
To provide stem cells which can be transplanted into people suffering from diabetes so that they could make their own insulin.
What is a disadvantage of cloning embryos?
It can be seen as un ethical because the embryo is a living thing.
Also some people are afraid that scientists will be able to clone humans in the future.
State 3 risks involved in cloning?
- There is a low rate of success. There were over 200 attempts to clone a sheep before Dolly was born.
- Research into human cloning raises many moral and ethical issues about creating life and then using it to help others.
- Dolly died of conditions linked to old age, yet she was only 7 years old. Her DNA may have already been old before she was born.
State 2 benefits of cloning?
Cloned pigs could make up for a shortage in transplant organs and patients needing a transplant would not have to wait for someone to die.
Diseases could be cured using embryonic stem cells.
What is the benefit of plants reproducing asexually?
This process produces new plants very quickly. In asexual reproduction there is no fertilisation between male and female gametes. New plants are produced using mitotic cell division only. The new plants are clones of the parent plant.
How can gardeners clone plants by cutting?
A short stem is cut off the parent plant with a sharp knife.
The end of the stem is dipped into plant hormone rooting powder. The hormone helps the plant to grow roots.
The cutting is put into a pot containing sandy soil.
A polyethene bag is then put over the plant to keep the moisture in.
What are the advantages of cloning plants?
All the plants are genetically identical. All the cuttings taken from a red rose grow into red ones.
Plants can take a long time to grow from seeds. cloning produces lots of identical plants more quickly.
Cloning enables growers to produce plants that are difficult to grow from seed such as bananas.
Can be used to preserve good characteristics.
What are the disadvantages of cloning plants?
The plants are all genetically identical. If the environment changes or a new disease breaks out all the plants would be affected in the same way. This could mean that they could all die.
Cloning plants over many years has resulted in little genetic variation because there is no mixing of genes.
Describe the process of aseptic technique?
Plants with the desired characteristics are chosen.
A large number of small pieces of tissue are taken from the parent plant.
They are put into sterile test tubes that contain growth medium.
The tissue pieces are left in suitable conditions to grow into plants.