Question

Which of the following is not a cell?

• A. Red Blood Corpuscle (RBC)
• B. Bacterium
• C. Spermatozoa
• D. Virus

Answer 1

The correct option is D

Virus

The correct option is D.

The explanation for the correct option:

1. A cell is a functional unit of life, which is illustrated by the definitive structures of the cytoplasm and the cell membrane, and possesses the tendency to perform essential metabolic activities.
2. The viruses are devoid of defined cellular composition.
3. They are formed of protein coat comprising genetic material, either in the form of DNA or RNA.
4. They do not possess the tendency to perform cellular activities.
5. They depend on the machinery of the host cell to do their metabolism and multiplication, thus, they are obligate parasites.
6. Therefore, a virus cannot be considered a cell.

The explanation for the incorrect options:

Option A:

1. The RBCs or the red blood corpuscles are the proper cells, which possess a nucleus at the young stage.
2. They possess the tendency to perform their metabolic activities via distinct pathways.
3. These cells carry oxygen from the lungs to the rest parts of the body.

Option B:

1. The bacterium is a prokaryotic cell, which possesses the tendency to perform cellular metabolism.
2. They are primarily free-living species, ubiquitous, and usually comprise one biological cell.
3. Salmonella and Streptococcus are some examples of bacteria.

Option C:

1. Spermatozoa are the haploid cells, which live for a short time duration, however, they possess cellular machinery to perform vital activities.
2. They are the male sex cells, which work to carry the genetic material of a male at the time of sexual reproduction.

Final answer: Virus is not a cell.