Question

The undefined nuclear region of prokaryotes is also known as

• A. nucleus
• B. nucleolus
• C. nucleoid

Answer 1

The correct option is C

nucleoid

The correct option is option C.

Explanation of the correct option:

1. The cell in which genetic material is not surrounded by a nuclear membrane and lacks all cell organelles (endoplasmic reticulum, Golgi apparatus, mitochondria) except ribosomes are called a prokaryotic cell.
2. Single organisms such as bacteria, and cyanobacteria are called prokaryotes.
3. The undefined region present inside a prokaryotic cell is the nucleoid, not surrounded by any membrane, thus it is called the nucleoid.

Explanation of the incorrect options:

Option A:

1. The nucleus contains the genetic material of a cell.
2. In prokaryotic as the genetic material is a single chromosome or circular DNA, that is not surrounded by a nuclear membrane.
3. In eukaryotic cells, the genetic material is surrounded by a nuclear membrane.

Option B:

1. The eukaryotic cell contains a smaller spherical-shaped structure inside the nucleus called the nucleolus.
2. Inside the fluid matrix of the nucleus (nucleoplasm), contains one or more spherical structures which are not surrounded by any membrane called the nucleolus.
3. It is the site for the synthesis of ribosomal RNA.

Final Answer: the undefined nuclear region of prokaryotes is also known as the nucleoid.