The part of the chromosome in the primary constriction with which the spindle fibres become connected during cell division is known as centromere. According to its position in the chromosome, the following classification can be made:
i) Telocentric Chromosome: Terminal centromere.
ii) Acrocentric Chromosome: Sub-terminal centromere.
iii) Sub-metacentric Chromosome: Sub-median centromere.
iv) Metacentric: Median Centromere