Q.Classify the chromosomes on the basis of position of centromere.

Based on centromere position, chromosomes are metacentric (centromere in the middle, equal arms), sub-metacentric (centromere slightly off-centre, unequal arms), acrocentric (centromere near one end, very unequal arms...

Four centromere-based chromosome types: metacentric, sub-metacentric, acrocentric, telocentric.

The position of the centromere along a chromosome determines the relative lengths of its two arms, and chromosomes are classified into four types on this basis (also reflected in their characteristic shape during anaphase movement, when the centromere leads): (1) Metacentric — centromere located exactly (or near) the middle, so the two arms are of roughly equal length; V-shaped at anaphase. (2) Sub-metacentric — centromere located slightly away from the middle, giving two visibly unequal arms; L-shaped at anaphase. (3) Acrocentric — centromere located close to one end, giving one very short arm and one very long a …