1. | Metaphase I | 2. | Metaphase II |
3. | Anaphase I | 4. | Anaphase II |
Assertion (A): | Meiosis is the mechanism by which conservation of specific chromosome number of each species is achieved across generations in sexually reproducing organisms. |
Reason (R): | Meiosis results in reduction of chromosome number by half in gametes. |
1. | Both (A) and (R) are True and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are True but (R) is not the correct explanation of (A). |
3. | (A) is True but (R) is False. |
4. | (A) is False but (R) is True. |
Statement I: | At Metaphase I the chromosomes align at the equator and the microtubules from opposite poles of the spindle get attached to the kinetochores of sister chromatids. |
Statement II: | At metaphase II the bivalent chromosomes align on the equatorial plate and microtubules from the opposite poles of the spindle attach to the kinetochore of homologous chromosomes. |
1. | Statement I is correct and Statement II is incorrect. |
2. | Statement I is incorrect and Statement II is incorrect. |
3. | Statement I is correct and Statement II is correct. |
4. | Statement I is incorrect and Statement II is correct. |
Column I | Column II | ||
A. | Carcinogen | 1. | Cancerous tumour |
B. | Anaphase-I | 2. | Disjunction |
C. | Mitotsis | 3. | Synapsis |
D. | Zygotene | 4. | Plectonemic coiling |
A | B | C | D | |
1. | 1 | 2 | 4 | 3 |
2. | 3 | 1 | 4 | 2 |
3. | 2 | 3 | 1 | 4 |
4. | 4 | 1 | 3 | 2 |
1. | synthesis of RNA and nucleotides |
2. | no change in DNA content |
3. | synthesis of histone proteins |
4. | growth phase of the cell |
1. | Same DNA content but double chromosome number |
2. | Four times DNA content but double chromosome number |
3. | Same DNA content but half chromosome number |
4. | Half DNA content but double chromosome number |
1. | Metaphase | 2. | Anaphase |
3. | Telophase | 4. | Prophase |