Q. No.In meiosis:
1.
A single round of DNA replication is followed by two sequential divisions with chromosome number and DNA content getting reduced twice
2.
A single round of DNA replication is followed by two sequential divisions with chromosome number getting reduced twice and DNA content getting reduced once
3.
A single round of DNA replication is followed by two sequential divisions with chromosome number getting reduced once and DNA content getting reduced twice
4.
A single round of DNA replication is followed by two sequential divisions with chromosome number and DNA content getting reduced once
The mechanisms that contribute to the genetic variation arising from sexual reproduction include:
| I: | Independent assortment of chromosomes |
| II: | Crossing over |
| III: | Random fertilization |
| 1. | I and II only | 2. | I and III only |
| 3. | II and III only | 4. | I, II and III |
A ribbon-like structure consisting of three protein components and extending across the region of synapsed chromosomes during the prophase of meiosis, is called:
| 1. | Phragmoplast | 2. | Phragmosome |
| 3. | Synaptonemal complex | 4. | Recombination nodule |
The point of contact between paired chromatids during meiosis, resulting in a cross-shaped configuration and representing the cytological manifestation of crossing over is called:
| 1. | Centromere | 2. | Centrosome |
| 3. | Chiasmata | 4. | Tetrad |
The most important significance of meiosis is that:
| 1. | It increases variations in the gene pool of the species that helps in evolution of that species. |
| 2. | It causes growth in the multicellular organisms. |
| 3. | It conserves specific number of chromosomes in each species across generations. |
| 4. | It is vital for repair and regeneration functions in the living organisms. |
Consider the following statements regarding meiosis:
| I: | At metaphase I, the microtubules from the opposite poles of the spindle attach to the pair of homologous chromosomes. |
| II: | At anaphase I, the homologous chromosomes separate, while sister chromatids remain associated with each other. |
Of the two statements:
1. Only I is correct
2. Only II is correct
3. Both I and II are correct
4. Both I and II are incorrect
During meiosis, the bivalent chromosomes clearly appear as tetrads first at:
| 1. | Zygotene of Prophase I | 2. | Pachytene of Prophase I |
| 3. | Metaphase I | 4. | Anaphase I |
Consider the following two statements:
| I: | The growth of multi-cellular organisms is due to mitosis. |
| II: | Mitosis results in the production of diploid daughter cells with identical genetic complement usually. |
Of the two statements:
1. Both I and II are correct and II explains I
2. Both I and II are correct but II does not explain I
3. I is correct but II is incorrect
4. I is incorrect but II is correct
During anaphase I of meiosis
1. Homologous chromosomes separate
2. Non-homologous autosomes separate
3. Sister chromatids separate
4. Non-sister chromatids separate
© 2024 GoodEd Technologies Pvt. Ltd.