During $........$,scientists discovered that a whole plant could be regenerated from an explant.

In which method is a group of cells suspended in a liquid medium?

Arrange the following steps of somatic hybridisation in a correct sequence.
$A$. Digestion of cell walls.
$B$. Isolation of naked protoplasts.
$C$. Fusion of protoplasts to get hybrid protoplast.
$D$. Isolation of single cells from two different varieties of plants.
$E$. Growing of hybrid protoplast to form a new plant.
Choose the correct answer from the options given below:

Pollen grains of a plant whose $2n = 28$ are cultured to get callus by tissue culture method. What would be the number of chromosomes in the cells of the callus?

The culture medium (nutrient medium) can be referred to as a 'highly enriched laboratory soil'. Justify the statement.

"Give me a living cell of any plant and $I$ will give you a thousand plants of the same type". Is this only a slogan or is it scientifically possible? Write your comments and justify them.