Crossing over that results in genetic recombination in higher organisms occurs between:
1. Non-sister chromatids of a bivalent
2. Two daughter nuclei
3. Two different bivalents
4. Sister chromatids of a bivalent
In the somatic cell cycle:
1. | DNA replication takes place in S-phase |
2. | A short interphase is followed by a long mitotic phase |
3. | \(G_2\) phase follows the mitotic phase |
4. | In the \(G_1\) phase, DNA content is double the amount of DNA present in the original cell |
Amount of cellular DNA increases during:
1. | Cytokinesis | 2. | Fertilisation |
3. | Mutation | 4. | Respiration |
If you are provided with the root tips of onion in your class and are asked to count the chromosomes, which of the following stages can you most conveniently look into?
1. Telophase
2. Anaphase
3. Prophase
4. Metaphase
Spindle fiber unites with which structure of chromosomes:
1. Chromocenter
2. Chromomere
3. Kinetochore
4. Centriole
The best material for the study of mitosis in the laboratory:
1. Anther
2. Root tip
3. Leaf tip
4. Ovary
If a diploid cell is treated with colchicine then it becomes:
1. Triploid
2. Tetraploid
3. Diploid
4. Monoploid
At which stage of the cell cycle does DNA replication occur:
1. G1 - phase
2. S - phase
3. G2 - phase
4. M - phase
The cells of the quiescent centre are characterised by:
1. Having dense cytoplasm and prominent nuclei
2. Having light cytoplasm and small nuclei
3. Dividing regularly to add to the corpus
4. Dividing regularly to add to tunica
Which one of the following precedes the reformation of the nuclear envelope during the M phase of the cell cycle:
1. | Decondensation from chromosomes and reassembly of the nuclear lamina |
2. | Formation of the contractile ring and formation of the phragmoplast |
3. | Formation of the contractile ring and transcription from chromosomes |
4. | Transcription from chromosomes and reassembly of the nuclear lamina |