What is an explant ?

An explant is :

why are the various components of the medium used for propagation of an explant in vitro?

Scientists have succeeded in recovering healthy sugarcane plants from a diseased one. Name the part of the parent plant used as explant by the scientists.

What is a thalamus ?What is its function?

Vidya got a plant which was affected with a viral disease. Her objective is to raise a disease free plant from this infected plant through tissue culture. State the reason for the selection of this part as the explant.

Vidya got a plant which was affected with a viral disease. Her objective is to raise a disease free plant from this infected plant through tissue culture. Which part of the plant should be selected as the explant?

What is work? What is it equal to?