During cell growth, DNA synthesis takes place in

 

1.	M phase	2.	S Phase
3.	G1 phase	4.	G2 phase

A bacterium divides every 35 minutes. If a culture containing 10⁵ cells per mL is grown for 175 minutes, what will be the cell concentration per mL after 175 minutes ? 

1. 175 × 10⁵ cells
2. 85 × 10⁵ cells
3. 35 × 10⁵ cells
4. 32 × 10⁵ cells

Best material for the study of mitosis in laboratory is
1. anther
2. root tip
3. leaf tip
4. ovary

In the somatic cell cycle:

If you are provided with 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?

At what stage of the cell cycle are histone proteins synthesized in a eukaryotic cell?
1. During telophase
2. During S-phase
3. During G₂ stage of prophase
4. During entire prophase

Four healthy people in their 20s got involved in injuries resulting in damage and death of a few cells. Which of the following cells are least likely to be replaced by new cells ?
1. Osteocytes
2. Liver cells
3. Neurons
4. Malpighian layer of the skin

Given below is a schematic break-up of the phases/stages of cell cycle. Which one of the following is the correct indication of the stage/phase in the cell cycle?

1. C-karyokinesis 2. D-synthetic phase 3. A-cytokinesis 4. B-metaphase

Synapsis occurs between
1. mRNA and ribosomes
2. Spindle fibers and centromere
3. Two homologous chromosomes
4. A male and a female gamete

During mitosis, endoplasmic reticulum and nucleolus begin to disappear at: