Differentiate between the following pairs on the basis of what is mentioned in the brackets:
Metaphase and Anaphase (Position of chromosomes)
Topic: Metaphase and anaphase
Answer
In METAPHASE the chromosomes are arranged at the EQUATOR of the cell, in a single plane, with the spindle fibres attached to their centromeres.
In ANAPHASE the centromeres have split and the daughter chromosomes (chromatids) are MOVING TOWARDS OPPOSITE POLES of the spindle.
The brackets restrict the answer to the POSITION OF CHROMOSOMES, so that is the basis: AT THE EQUATOR in metaphase, MOVING TO THE POLES in anaphase.
THE EVENT THAT SEPARATES THEM is the splitting of the CENTROMERE. Until that instant the two chromatids are one chromosome; the moment it divides they become two independent chromosomes and begin to move apart.
IDENTIFYING THEM IN A DIAGRAM: chromosomes in a neat line across the middle is metaphase; V or J shaped chromosomes being dragged apart is anaphase — they bend because the spindle pulls at the centromere and the arms trail behind.
| Point of difference | Metaphase | Anaphase |
|---|---|---|
| Position of chromosomes | At the equator, in one plane | Moving towards opposite poles |
| Centromere | Intact; chromosomes still double | Split; chromatids now separate |
| Shape seen | Lined up across the middle | V or J shaped, dragged by the fibres |