NEET BIOLOGY

REPRODUCTION

REPRODUCTION IN ORGANISMS

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
When do homologous chromosomes line up along the middle of the cell in meiosis?
A
telophase II
B
anaphase I
C
prophase II
D
metaphase I
Explanation: 

Detailed explanation-1: -During metaphase I, all of the doubled homologous chromosome pairs line up along the midline of the cell between the two centrioles. During anaphase I, the homologous chromosome pairs separate and are pulled to opposite poles of the cell by spindle fibers attached to the centrioles.

Detailed explanation-2: -In metaphase I, the homologous pairs of chromosomes align on either side of the equatorial plate. Then, in anaphase I, the spindle fibers contract and pull the homologous pairs, each with two chromatids, away from each other and toward each pole of the cell. During telophase I, the chromosomes are enclosed in nuclei.

Detailed explanation-3: -Metaphase: During metaphase, each of the 46 chromosomes line up along the center of the cell at the metaphase plate.

Detailed explanation-4: -During prophase I, homologous chromosomes pair up and exchange sections of DNA. This is called recombination or crossing over. This is followed by metaphase I where the connected pairs of chromosomes align at the middle of the cell.

There is 1 question to complete.