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Question
Explain the types of chromosomes on the basis of position of centromere.
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Solution
Chromosomes can be classified into four types on the basis of position of centromere:
a. Metacentric:
Centromere is in the middle of the chromosome and hence, the two arms are nearly equal.
Chromosome looks ‘V’-shaped in anaphase.
b. Submetacentric:
Centromere is not in the center but some distance away from the centre of
chromosomes and therefore arms are unequal in length.
The chromosome appears ‘L’ shaped in anaphase.
c. Acrocentric:
Centromere is near one end of the chromosome. One arm is very short, while other is long.
d. Telocentric:
Centromere is at the extreme tip of the chromosome.
The arm is only on one side.
Chromosome remains rod shaped even in anaphase.
Chromosome appears ‘i’ shaped.
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