Question

Differentiate between X-chromosome and Y-chromosome with reference to –
i. Length of non-homologous regions

Hint:

The position of the centromere helps in classifying chromosomes and determining their behavior during cell division.

Answer 1

Step 1: Understanding X and Y chromosomes.
X and Y chromosomes are sex chromosomes that determine the biological sex of an individual.
- The X chromosome is larger and has more non-homologous regions.
- The Y chromosome is smaller and has relatively fewer non-homologous regions compared to the X chromosome.
Step 2: Conclusion.
The X chromosome has a greater length of non-homologous regions compared to the Y chromosome.
ii. Type as per position of centromere.
Solution:
Step 1: Position of Centromere.
The centromere is the region where the two chromatids are held together.
- The X chromosome has a centromere located closer to the middle, making it a metacentric chromosome.
- The Y chromosome has a centromere located towards one end, making it a submetacentric chromosome.
Step 2: Conclusion.
The X chromosome is metacentric, while the Y chromosome is submetacentric.