Give an account on cryopreservation.

Explanation

Crypreservation is a technique of preserving plant materials under very low temperature of -`195^@C` using liquid nitrogen .
The plant materials used for Cryopreservation and protoplasts, cells , tissues, organelles, organs, extracellular matrix, enzymes and any other material. The plant materials are in dormant stage under this very low temperature,as all the enzyme activity and chemical activity of plant material will be stopped at the extreme low temperature. These activities can be brought to normal by bringing to normal room temperature for any experimental work . Cryprotects like dimethyl sulphoxide, glycerol or sucrose are added before cryopreservation. They protect cells or tissues from the stress of freezing temperature.