The stage during which separation of the paired homologous chromosomes begins is
1. | Pachytene | 2. | Diplotene |
3. | Diakinesis | 4. | Zygotene |
The enzyme recombinase is required at which stage of meiosis
1. Pachytene
2. Zygotene
3. Diplotene
4. Diakinesis
Crossing over that results in genetic recombination in higher organisms occurs between:-
1. Non-sister chromatids of a bivalent
2. Two daughter nuclei
3. Two different bivalents
4. Sister chromatids of a bivalent
The fruit fly has 8 chromosomes (2n) in each cell. During the interphase of mitosis, if the number of chromosomes at G1 phase is 8, what would be the number of chromosomes after the S phase?
1. | 4 | 2. | 32 |
3. | 8 | 4. | 16 |
Spindle fibres attach on to
1. kinetochore of the chromosome
2. centromere of the chromosome
3. kinetosome of the chromosome
4. telomere of the chromosome
1. | Complete disintegration of nuclear envelope takes place. |
2. | Chromosomes are highly condensed. |
3. | Metaphase chromosomes are made up of four sister chromatids held together by centromere. |
4. | Chromosomes lie at the equator of the cell. |
Amount of cellular DNA increases during:
1. | Cytokinesis | 2. | Fertilisation |
3. | Mutation | 4. | Respiration |
The stage of mitosis shown in the given diagram is:
|
Humans have a haploid chromosome number n = 23. How many tetrads will be formed during meiosis?
1. | 23 | 2. | 46 |
3. | 69 | 4. | 92 |
The human meiocyte shows 92 chromatids at the end of S phase. The number of centromeres in this cell will be:
1. | 23 | 2. | 46 |
3. | 69 | 4. | 92 |