Cell Cycle and Cell Division PYQ's

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Previous Year Questions:

1. Spindle fibers attach to kinetochores of chromosomes during                                              (2024)

1) Prophase        2) Metaphase
3) Anaphase       4) Telophase

Ans. 2 - Metaphase

Explanation: The key feature of metaphase are: 1. Spindle fibers attach to kinetochores of chromosomes. 2. Chromosomes are moved to spindle equator and get aligned along metaphase plate through spindle fibers to both poles.

2. Given below are two statements:                                                                                             (2024)

Statement I: Chromosomes become gradually visible under light microscope during leptotene stage.
Statement II: The beginning of diplotene stage is recognized by dissolution of synaptonemal complex.

In the light of the above statements, choose the correct answer from the options given below:

1) Both statement I and statement II are true.
2) Both statement I and statement II are false.
3) Statement I is true but statement II is false.
4) Statement I is false but statement II is true.

Ans. 1 - Both statement I and statement II are true. 

Explanation: During leptotene stage the chromosomes become gradually visible under the light microscope. The beginning of diplotene is recognized by the dissolution of the synaptonemal complex and the tendency of the recombined homologous chromosomes of the bivalents to separate from each other except at the sites of crossover.


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