I: | Gametes contain half the number of chromosomes found in somatic cells. |
II: | Somatic cells have the diploid number of chromosomes. |
III: | The haploid number of chromosomes in humans is 23. |
IV: | The diploid number of chromosomes in humans is 23 pairs. |
The Mitotic phase of a typical eukaryotic cell is divided into:
1. | Two stages | 2. | Three stages |
3. | Four stages | 4. | Five stages |
1. | Skin epithelial cell | 2. | Neuron |
3. | Fibroblast | 4. | Phagocytes |
Assertion (A): | Mitosis is also called as equational division. |
Reason (R): | The number of chromosomes in the parent cells undergoing mitosis and progeny cells is the same. |
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. |
Which of the following does not take place during telophase of mitosis?
1. | Chromosomes become discrete. |
2. | Nuclear envelope reforms. |
3. | Chromosomes cluster at opposite spindle poles. |
4. | Nucleolus, endoplasmic reticulum, and Golgi complex reform. |
1. | The interphase lasts more than 95% of the duration of the cell cycle. |
2. | M phase starts with the nuclear division. |
3. | Interphase is the resting stage in the cell cycle where the cell is metabolically inactive. |
4. | Neurons in human body are permanently in G0 phase of the cell cycle. |
1. | interkinesis and there is no replication of DNA during this stage. |
2. | interkinesis and there is replication of DNA during this stage. |
3. | interphase II and there is no replication of DNA during this stage. |
4. | interphase II and there is replication of DNA during this stage. |
Organisms prefer sexual mode of reproduction in adverse conditions because:
1. | It leads to a rapid proliferation of numbers |
2. | It requires two individuals that can support the progeny |
3. | It is less energy consuming than the asexual mode of reproduction |
4. | It provides protection and increases variations that may help progeny to survive |
Identify the correct statement regarding meiosis amongst the following:
I: | Meiosis involves two sequential cycles of nuclear and cell divisions but only a single cycle of DNA replication. |
II: | Meiosis II is initiated after the parental chromosomes have replicated to produce identical sister chromatids at the S phase. |
III: | Meiosis involves pairing of bivalents and recombinations between them. |
1. | I only | 2. | I and II only |
3. | I and III only | 4. | I, II and III |