Select the correct statement about G₁ phase
1. Cell is metabolically inactive
2. DNA in the cell does not replicate 
3. It is not a phase of synthesis of macromolecules
4. Cell stops growing

In bacteria the cell cycle is divided into:
1. Only 1 phase
2. Two stages
3. Three periods
4. Four classes

The G₀ stage of the cell cycle is irreversible in:
I. Quiescent cells
II. Senescent cells
III. Terminally differentiated cells

1. I and II only
2. I and III only
3. II and III only
4. I, II and III

If a cell in S phase is fused with a cell in G₁:
1. The G₁ nucleus immediately enters the S phase
2. The S nucleus stops DNA replication
3. The G₁ nucleus directly enters G₂ phase
4. Both nuclei enter the M phase immediately

A point in the animal cell cycle, at which the cell becomes "committed" to the cell cycle, occurs in:

During what phase in the cell cycle would you find the most DNA per cell?

The phase of the cell cycle that is expected to be the most variable in duration in different types of cells in an animal will be:

Onion root tip has 16 chromosomes in each cell. How many chromosomes will the cell respectively have at G₁ phase, after S phase and after M phase?

Destruction of both centrosomes with a laser beam in an animal cell:

1. will prevent both mitosis and cytokinesis

2. prevents cytokinesis even if mitosis has been completed normally

3. permits cytokinesis but the daughter cells fail to enter a new S phase

4. prevents mitosis but permits cytokinesis

Which of the following statements is not true for cancer cells in relation to mutations?
1. Mutations in proto-oncogenes accelerate the cell cycle.
2. Mutations destroy telomerase inhibitor.
3. Mutations inactivate the cell control.
4. Mutations inhibit production of telomerase.