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Genetic inheritance - part two - EdexcelCloning in plants

We inherit our sex (male or female) and blood group from our parents. Genetic disorders can also be inherited. Selective breeding occurs when humans breed plants and animals for specific characteristics. Cloning (often in plants and not in humans) makes genetically identical copies of the one parent organism.

Part of Biology (Single Science)Genetics

Cloning in plants

are genetically identical individuals. The of plants has many important commercial implications. It allows a variety of a plant with desirable characteristics to be produced cheaply, quickly and on a large scale. Cloning often follows . It allows many copies of the new organism to be produced.

Cuttings

The simplest way to clone a plant involves taking a . This is an old but simple technique, used by gardeners. A branch from the parent plant is cut off, its lower leaves are removed, and the stem is planted in damp compost. Plant hormones are often used to encourage new roots to develop. The cutting is usually covered in a clear plastic bag to keep it moist and warm. After a few weeks, new roots develop and a new plant grows.

Tissue culture

Another way of cloning plants is by . It works with small pieces of plants, called . These are grown using sterile that contains plant hormones and nutrients. This makes tissue culture more expensive and difficult to do than taking cuttings. This is an important way to preserve rare plant species or grow commercially in larger nurseries.

Diagram showing how plants can be cloned
Figure caption,
The process of cloning plants by tissue culture

Cloning expensive food crops has been carried out for many years, and causes the public fewer and moral concerns than animal cloning.