Question

In which type of chromosome, one arm is very long and one arm is very short
A. Acrocentric
B. Metacentric
C. Submetacentric
D. Telocentric

Answer 1

Hint: Different types of the chromosome can be divided on the bases of the number of the centromeres, location of the centromere, function and autosomal or sex chromosomes.

Complete Answer:
- Chromosome is the thread-like structures present in the nuclei of the animal and plant cells and it is made up of the histone protein and DNA or RNA depending upon the genetic material of the organisms.
- Two arms present in the structure of the chromosome are known as p and q arms.

Now on the bases of length of the two arms, chromosome have different types that is:
1. Metacentric: This is the type of chromosome in which the lengths of p and q arms are equal and centromere is present at the centre of the chromosome. In human chromosomes examples are chromosome 1, 3, 16 and chromosome 19.
2. Submetacentric: This the type of chromosome in which the centromere of the chromosome is present is slightly shifted thus, p arm is shorter as compared to the p arm. Examples are chromosome 2, 4, 12 and X.
3. Acrocentric: In this type of the chromosome the centromere is more shifted towards the end of the chromosome making the p arm very short as compared to the q arm. Thus, the p arm is very short and the q arm is longer. Examples are chromosome 13, 14, 15 and Y chromosome.
4. Telocentric: In this type, the centromere of the chromosome is present at the ends of the chromosome and thus only one arm is present. So, only the q arm exists and there is no p arm. And this type of chromosome is not found in the human genome.

Thus, after discussion we can say that option ‘A’ is the correct option.

Note: The classification of the chromosomes used to solve this question is on the bases of location of the chromosomes. And chromosomes help in the determination of the sex of zygote and ensures the smooth cell division required for proper growth of the zygote.