Cell Cycle Phases and Factors

Which of the following factors significantly influences the duration of the cell cycle?

In which phase does the cell primarily undergo growth and organelle duplication?

Which statement about cell signals is inaccurate?

Which of the following cells would likely have the longest cell cycle duration?

What is the estimated duration of the cell cycle in a meristematic cell?

Which factor does not influence the duration of the cell cycle?

In which phase of the cell cycle do cells primarily perform daily metabolic activities?

Which of the following statements about cellular signals is true?

Which type of cells are typically found in the GO phase?

Rank the following cell types in order of increasing cell-cycle duration.

What is the estimated duration of the mitotic phase for meristematic cells in onion roots?

In which phase does a cell primarily increase its organelle count and grow?

Which statements about cell cycle activities is true?

Cell Cycle Phases

The cell cycle has four main phases:
- The first growth phase (G1)
- The synthesis phase (S)
- The second growth phase (G2)
- The division phase (M)
The G1 phase marks the start of cell growth.
Cells remain inactive and carry out their functions during the GO phase (also known as the resting phase).
The cell duplicates its DNA in the S phase, leading to an increase in DNA content.
In the G2 phase, the cell prepares for division and continues to grow.
The M phase includes mitosis where the cell divides into two daughter cells.

Factors Affecting The Cell Cycle

Cell type: The duration of the cell cycle varies between different cell types.
Environmental conditions: The cell cycle can be affected by external factors such as temperature and nutrient availability.
Cellular signals: Internal and external signals regulate the progression of the cell cycle. Internal examples include nutrients, energy levels, and DNA damage. External examples include growth factors.

Cell Cycle Duration

Meristematic cells in the root tip: These cells divide rapidly, with a cell cycle time of approximately 2 hours.
Nerve cells: Generally remain in the GO phase.
Liver cells: Can enter the cell cycle (G1 phase) when needed.
Muscle cells: Generally remain in the G1 phase.
Epithelial cells (lining the intestines): These cells have a short cell cycle time, actively replacing damaged cells.
Cell cycle duration for different cell types:
- Epithelial cells: 4-18 hours
- Nerve cells: Resting state (Go)
- Meristematic cells: 2 hours
- Liver cells: Around 18 hours
- Muscle cells: Typically in G1.

Cell Growth and Organelles

The cell grows and increases the number of organelles during both G1 and G2 phases.
The amount of DNA in the nucleus before division is halved after mitosis.

Explore the four main phases of the cell cycle, including G1, S, G2, and M phases. Learn about the various factors that can affect the duration and progression of the cell cycle in different cell types. This quiz will deepen your understanding of cellular processes and regulations.