State the functions of the following:
Centromere:
Topic: Centromere
Try it
Pick an option and check your answer. The full worked answer is below either way.
Answer
(a) It is the point of attachment of two sister chromatids.
The CENTROMERE is the constricted point at which the two identical SISTER CHROMATIDS of a duplicated chromosome are joined.
It does two jobs: it holds the chromatids together until anaphase, and it is the point to which the SPINDLE FIBRES attach in order to pull them apart.
THE DEFINING EVENT OF ANAPHASE is the splitting of the centromere. Until that moment the two chromatids are one chromosome; the instant it divides they become two independent chromosomes.
The wrong options all substitute a similar-sounding word — centrioles, centrosomes — which is the standard way this question is built. Keep the three apart: CENTROMERE is on the CHROMOSOME, CENTRIOLES and the CENTROSOME are in the CYTOPLASM.
It is the point of attachment of two sister chromatids.