Question

The plants developed by tissue culture of a specific plant tissue or part are known as ________.

• A. somatic hybrids
• B. somaclones
• C. cambium
• D. explants

Answer 1

The correct option is B somaclones

Tissue culture is the technique of growing plant cells, tissues or organs in a sterile culture medium under controlled environmental conditions. It helps in fast propagation of plants and is also known as micropropagation.

Explant refers to any plant part, tissue or cell that is used to produce multiple plants via tissue culture. As each plant in tissue culture is generated due to repeated mitotic divisions of the cells of the explant, there is no genetic variation (differences in the characteristics of different members of the same species) introduced in the plant. All explants collected from a single parent plant will give rise to young plants that are genetically identical to each other and to the parent plant. Thus, these plants are known as somaclones.

A clone refers to a cell, group of cells, or organism that is produced asexually and is genetically identical to a single ancestor.

A somatic hybrid is formed by the protoplast (plant cell devoid of cell wall) fusion of two genetically different somatic (cells other than germ cells) cells. For this, the cell wall and cell membrane of the plant cells are removed and the isolated protoplasts are fused to form a hybrid cell. The resultant hybrid has characteristics of both parents and is genetically different from them. Example is pomato, a somatic hybrid formed between potato and tomato.

Cambium refers to the layer proliferating cells that develop to cause secondary growth in certain plants. It may form more vascular tissues, cork or secondary cortex.