What is not seen during mitosis in somatic cells
Important Questions on Cell Division
Arrange the following statements on meiosis in a correct sequence.
A) Terminalisation of chiasmata.
B) Dissolution of synaptonemal complex.
C) Homologous chromosome separation.
D) Appearance of recombination nodules.
E) Pairing of homologous chromosomes.
F) Disappearance of nuclear envelope.
Pair of homologous chromosomes
Tetrad of chromatids
Bivalent chromosomes
Recombination modules of non sister chromatids
| Column-I | Column–II | ||
| a. | Pachytene | (i) | The pairing of homologous chromosomes |
| b. | Metaphase I | (ii) | Terminalization of chiasmata |
| c. | Diakinesis | (iii) | Crossing-over takes place |
| d. | Zygotene | (iv) | Chromosomes align at the equatorial plate |
Assertion In crossing over, the exchange of genetic material between two homologous chromosomes occur during both mitotic and meiotic cell divisions.
Reason The process of crossing over is only possible and is mediated by recombinase.
The correct answer is:
i. Crossing over
ii. Synapsis
iii. Terminalisation of chiasmata
iv. Disappearance of the nucleolus
Match the changes which occur in the chromosomes during meiosis, with the different phases of prophase-I.
| List - I | List - II | ||
| (a) | Pachytene | (i) | Compaction of chromosomes |
| (b) | Zygotene | (ii) | Terminalisation of chiasmata |
| (c) | Diplotene | (iii) | Pairing of chromosomes |
| (d) | Leptotene | (iv) | Dissolution of synaptonemal complex |
| (v) | Recombination nodule |
The correct answer is
Match the following with respect to meiosis
| (a) | Zygotene | (i) | Terminalization |
| (b) | Pachytene | (ii) | Chiasmata |
| (c) | Diplotene | (iii) | Crossing over |
| (d) | Diakinesis | (iv) | Synapsis |
Select the correct option from the following
| I | II | ||
| () | Synapsis aligns homologous chromosomes | () | Anaphase – II |
| () | Synthesis of RNA and protein | () | Zygotene |
| () | Action of enzyme recombinase | () | – phase |
| () | Centromeres do not separate but chromatids move towards opposite poles | () | Anaphase – I |
| () | Pachytene |
