In prophase I of Meiosis, chromosomes start pairing together and synapsis takes place. This process occurs during which of the following stage?
1. | Pachytene | 2. | Diplotene |
3. | Leptotene | 4. | Zygotene |
Given below are two statements : One is labeled as Assertion (A) and the other is labeled as Reason (R)
Assertion (A): | The growth of the multicellular organism is due to mitosis |
Reason (R): | Mitosis is also called as equational division and it offers genetic stability |
In light of the above statements choose the correct answer from the options given below:
1. | (A) is correct but (R) is not correct. |
2. | (A) is not correct but (R) is correct. |
3. | Both (A) and (R) are correct and (R) is the correct explanation of (A). |
4. | Both (A) and (R) are correct but (R) is not the correct explanation of (A). |
Given below are two statements: One is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A): | The beginning of diplotene is recognised by the dissolution of the synaptonemal complex and formation of X shaped structures called chiasmata |
Reason (R): | In oocytes of some vertebrates, diplotene can last for months or years. |
In the light of the above statements, choose the correct answer from the options given below:
1. | (A) is correct but (R) is not correct. |
2. | (A) is not correct but (R) is correct. |
3. | Both (A) and (R) are correct and (R) is the correct explanation of (A). |
4. | Both (A) and (R) are correct but (R) is not the correct explanation of (A). |
The oocytes of some vertebrates get arrested for years or months in:
1. | Telophase - I | 2. | Diplotene |
3. | Diakinesis | 4. | Metaphase - I |
Select the correct sequence of events occurring during Prophase-I of Meiosis-I:
(a) | Nuclear envelope breakdown |
(b) | Synaptonemal complex formation |
(c) | Compaction of chromosomes |
(d) | Terminalisation of chiasmata |
(e) | Crossing over |
Choose the most appropriate answer from the options given below:
1. (c) → (b) → (e) → (d) → (a)
2. (c) → (a) → (b) → (d) → (e)
3. (b) → (c) → (a) → (d) → (e)
4. (c) → (a) → (b) → (e) → (d)
a. | Synapsis of homologous chromosomes |
b. | Chromosomes become gradually visible under a microscope |
c. | Crossing over between non-sister chromatids of homologous chromosomes |
d. | Terminalisation of chiasmata |
e. | Dissolution of synaptonemal complex |