Question

Cellular totipotency is demonstrated by
A. Only gymnosperm cells
B. All plant cells
C. All eukaryotic cells
D. Only bacterial cells

Answer 1

Hint: Totipotency refers to an ability where complete growth of an organism from a single cell can take place.

Complete answer:
In Latin the meaning of totus is “entirely” and potens means having power.
Cellular totipotency can mean two things:
- Capability of a single cell to develop into a complete individual.
- Capability to form or differentiate into any other specialized cell in an organism.
Both of these abilities are shown by plant cells, they can maintain totipotency and plasticity even in their differentiated form. Plant cells show differentiation, dedifferentiation, and redifferentiation. Totipotency can also be explained as the genetic potential of a plant cell to produce the entire plant.

Additional Information:
- This property of cellular totipotency seen in plants is used widely in tissue culture techniques, which involves the growing and management of plant cells, organs, and tissues in an artificial growth medium. Due to cellular totipotency, any plant part or cell can give rise to a new plant.
- The plant part that is used in tissue culture is known as explant.
- G. Habertlandt was the first to demonstrate tissue culture and is known as the Father of Tissue Culture.
- Different types of plant tissue culture techniques are as follows:
Callus Culture
Suspension Culture
Meristem Culture
Protoplast Culture
- Differentiation: It is the process of maturation of cells to perform specific functions.
- Dedifferentiation: It is when differentiated cells that had lost their ability to divide, regain that ability.
- Redifferentiation: It is the process by which dedifferentiated cells again lose their ability to divide and mature to perform specific functions.

So, the correct answer is, ‘Cellular totipotency is demonstrated by all plants' cells’.

Note: It has to be remembered that totipotency not only means the ability to give rise to a completely new individual plant cell but also to form or differentiate any other specialized type of cell. The plant formed from the single-cell exhibiting cellular totipotency is an identical copy of the parent. They are known as clones.