The centrosome duplicates during:
| 1. | Early Prophase | 2. | Late Prophase |
| 3. | S phase | 4. | G2 phase |
Prophase of mitosis is not characterized by:
| 1. | condensation of chromatin |
| 2. | migration of centrosomes to opposite poles |
| 3. | formation of mitotic apparatus |
| 4. | pairing of homologous chromosomes |
The start of the second phase of mitosis, metaphase, is marked by:
| 1. | complete disintegration of the nuclear envelope |
| 2. | alignment of chromosomes at the equatorial plate |
| 3. | de-condensation of chromatin |
| 4. | reappearance of the nucleolus |
Consider the given two statements:
| I: | Morphology of chromosomes is best studied at metaphase |
| II: | At this stage, a chromosome is made up of two sister chromatids, held together at the centromere |
1. Both I and II are True and II explains I
2. Both I and II are True but II does not explain I
3. I is True but II is False
4. I is False but II is True
All the following key events take place during telophase of mitosis except:
| 1. | Chromosomes cluster at the opposite spindle poles |
| 2. | Chromosomes become discrete |
| 3. | Nuclear envelope reforms |
| 4. | Nucleolus, ER and Golgi complex reform |
Liquid endosperm in coconut forms due to:
| 1. | Failure of cytokinesis after karyokinesis |
| 2. | Failure of karyokinesis before cytokinesis |
| 3. | Disruption of spindle fibers at metaphase |
| 4. | Continued DNA replication during cytokinesis |
During which stage of mitosis do the following events occur?
| I: | Centromeres split and chromatids separate |
| II: | Chromatids move to opposite poles |
| 1. | Prophase | 2. | Metaphase |
| 3. | Anaphase | 4. | Telophase |
Match each item in Column I with one in Column II and select the correct answer from the codes given below:
|
Column I |
|
Column II |
|
|
A |
Zygotene |
a |
Pairing of homologous chromosomes |
|
B |
Pachytene |
b |
Appearance of chiasma |
|
C |
Diplotene |
c |
Terminalization of chiasma |
|
D |
Diakinesis |
d |
Crossing over |
Codes:
| A | B | C | D | |
| 1. | a | c | b | d |
| 2. | a | d | b | c |
| 3. | a | b | c | d |
| 4. | b | c | d | a |
All the following are significances of mitosis except:
| 1. | Restoration of nuclear/cytoplasmic ratio |
| 2. | Growth of living organisms |
| 3. | Replacement of lost cells |
| 4. | Generation of genetic variation |
The correct chronology of stages of Prophase I is:
| 1. | Leptotene – Zygotene – Pachytene – Diplotene – Diakinesis |
| 2. | Leptotene – Pachytene – Zygotene – Diplotene – Diakinesis |
| 3. | Leptotene – Zygotene – Pachytene – Diakinesis – Diplotene |
| 4. | Zygotene – Leptotene – Pachytene – Diakinesis – Diplotene |