Question

A telocentric chromosome differs from an acrocentric chromosome in that
(a) The former have sub-terminal centrally located centromeres.
(b) The centromere in the former is terminal and the latter has a medially located centromere.
(c) The former has a subterminal centromere and the latter has a medially located centromere.
(d) The former has a terminal and the latter has subterminal centromere.

Answer 1

Hint: They can be seen in I and J shapes during anaphase of the cell division depending upon the position of the centromere in the chromosomes.

Complete answer:
A telocentric and an acrocentric chromosome differ from each other based on the position of the centromere. The telocentric chromosomes are present at the end or terminal of the chromosomes while the acrocentric chromosome is present between the center and the terminal, which is at the sub-terminal position.

Figure: Types of chromosome

The acrocentric chromosomes are the chromosomes where the centromere is placed away from the center hence giving rise to one of the very long parts of the arm and one very short part of the arm in p and q terms, Whereas the telocentric chromosomes are the chromosomes in which the centromere is present at the very end of the chromosome Some more differences between telocentric and acrocentric chromosomes are as follows:

Characteristics	Acrocentric chromosome	Telocentric chromosome
Structure	These chromosomes are composed on very short and one very long part	These chromosomes are rod-shaped.
Presence in humans	They are present in humans	They are absent in humans
Presence of SAT chromosomes	SAT chromosomes are present	SAT chromosomes are absent
Presence of p and q arms	p and q arms can be observed, in some cases, the short arm is barely seen in them.	Only one arm is observed

So, the correct answer is ‘the former has a terminal and the later has subterminal centromere’.

Note: Each chromosome can be divided into two sections or arms based on the position of the centromere the shorter arm is called p and the longer arm is called q. Due to the position of the centromere, these chromosomes can be seen in different kinds of shapes during the anaphase of mitosis where the telocentric chromosome appears to be like I shape and the acrocentric chromosome appears in J shape. SAT chromosome is also known as a satellite chromosome is a chromosomal segment that is separated from the main body of the chromosome by a secondary constriction.