Question

When the centromere is situated in the middle of two equal arms of chromosomes, the chromosome is referred as

• A. Acrocentric
• B. Metacentric
• C. Telocentric
• D. Sub-metacentric

Answer 1

The Correct Option is B

To understand the classification of chromosomes based on the position of the centromere, we must first understand what a centromere is. The centromere is a region on a chromosome that joins two chromatids (exact copies of a chromosome). Depending on where the centromere is located, chromosomes can be classified into the following types:

1. Metacentric Chromosomes: In these chromosomes, the centromere is positioned in the middle, resulting in two arms of equal length. These chromosomes resemble a "V" shape during cell division.
2. Submetacentric Chromosomes: The centromere is slightly off-center, creating one arm longer than the other. These appear like an "L" shape.
3. Acrocentric Chromosomes: Here, the centromere is near one end, making one very long arm and one very short arm, giving them a "J" shape.
4. Telocentric Chromosomes: The centromere is located at the end of the chromosome. This results in a chromosome with only one arm.

Given the details in the question, the correct answer is:

Metacentric: When the centromere is situated in the middle of two equal arms of chromosomes, it is referred to as metacentric. This results in two symmetrical arms of equal length.

The options provided in the question refer to different configurations of chromosome structures, and "Metacentric" clearly fits the description of having the centromere centrally located.

Therefore, the correct option is Metacentric.