f215 module 2 chapter 1

F215 - Module 2 chapter 1 - Cloning in Plants and Animals

1. Outline the differences between reproductive and non-reproductive cloning

         Reproductive cloning:

·         Making cloned animals using eggs and sperm.

·         Splitting embryos to make artificial identical twins.

·         Nuclear transfer by taking a differentiated cell from an adult and placing it into an egg with its nucleus.

Non-reproductive cloning:

·         Using cloned cells to generate cells, tissues and organs to replace those damaged.

·         Use totipotent cells (capable of differentiating into any adult cell).

·         To repair damage, not to make new organisms.

Sometime known as therapeutic cloning.

b. Describe the production of natural clones in plants using the example of vegetative propagation in elm trees

Asexual reproduction after damage to the parent plant.

1.     A healthy elm tree has a root sucker which grows a new tree.

2.    The elm tree starts to show signs of Dutch elm disease.

3.    The main stem is dead but the roots are still alive so root suckers are still produced.

4.    Root suckers grow producing new trees.

The root suckers are sometimes known as basal sprouts and they grow from the meristem tissue in the trunk close to the ground.

c. Describe the production of artificial clones of plants from tissue culture

·         Taking cuttings:

A section of stem is cut between leaf joints (nodes).

The cut end of the stem is treated with plant hormones.

The cutting forms a new plant which is a clone of the original parent plant.

·         Grafting:

A shoot section of a woody plant is joined to an already growing root and stem (stock).

The graft grows and is genetically identical to the parent plant but…