Question

Cell principle is not applicable to
a. Bacteria
b. Viruses
c. Algae
d. Fungi

Answer 1

Hint: According to the Cell principle, a cell is a fundamental unit of life and exhibits all the structural and functional properties of an organism. This principle also states that cells are made from pre-existing cells. All organisms are made up of cells. Organisms can be unicellular or multicellular depending upon the number of cells they have.

Complete answer:
> The basic principle of biology is Cell theory that states that a cell is the fundamental unit of life. All living organisms consist of cells. The cell principle is not applicable to the virus because viruses are not true cells. They lack the protoplasm that is the most important part of the cell. It contains DNA or RNA; the outer coat is of the capsid that is made up of protein. As cells are absent in the virus so no cell division occurs. It replicates only inside the body of a living host cell.

> Bacteria is a unicellular organism that contains only one cell. Cell division occurs.

> Algae is an aquatic organism that has the potential to conduct photosynthesis. Some algae are unicellular whereas others are multicellular.

> Fungi is a eukaryotic organism. It can be unicellular or multicellular organisms.

Hence, the correct answer is option (B).

Additional information:
- A virus is a microscopic and infectious agent that multiplies only inside the cells of living organisms.
- Viruses infect all organisms such as plants, animals, and microorganisms (Bacteria).
- The lifecycle of the virus is classified as lytic or lysogenic.
- Bacteria are microscopic organisms that exist both inside and outside the organisms.
- Algae and Fungi vary from unicellular organisms to complex multicellular organisms.

Note: Cell principle states that all living organisms are made up of one or more cells. The basic unit of structure and organization in organisms is a cell. Cells are made from pre-existing cells. Cell theory does not apply to those organisms which lack true cells. For example, viruses lack true cells, so this theory is not applicable to a virus.