Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): During metaphase, each chromosome gets aligned at the equator with spindle fibres from opposite poles attached to it. Reason (R): Small disc-shaped structures at the surface of the centromeres called kinetochores serve as the sites of attachment of spindle fibres. In the light of the above statemen

Step-by-step solution

Assertion (A) is correct because a key event of metaphase is the alignment of all chromosomes at the metaphase plate (equator), where they are connected to spindle fibres from both poles. Reason (R) is correct because kinetochores are indeed the disc-shaped protein structures on the centromeres where spindle fibres attach. Reason (R) correctly explains Assertion (A) because it is precisely the attachment of spindle fibres to these kinetochores from opposite poles that allows the physical pulling and positioning of