Worksheet: The Cell Cycle

Biology – Grade 9

Fill in the Blanks:

1. The cell cycle is divided into two main phases: _______ and _______.
2. During the S phase of interphase, _______ is replicated.
3. G₁, S, and G₂ phases together make up the _______ phase.
4. Cells that no longer divide exit the cell cycle and enter the _______ phase.
5. The phase where the cell physically divides is called _______.

Multiple Choice Questions (MCQs):

1. Which phase of the cell cycle involves DNA replication?
   • A) G₁ phase
   • B) S phase
   • C) G₂ phase
   • D) Mitosis
2. What is the longest phase of the cell cycle?
   • A) Prophase
   • B) Metaphase
   • C) Interphase
   • D) Cytokinesis
3. Which process directly follows mitosis?
   • A) G₁ phase
   • B) DNA replication
   • C) Cytokinesis
   • D) G₂ phase

Match the Columns:

A	B
1. G₁ phase	a. DNA replication
2. S phase	b. Cell grows and prepares for DNA synthesis
3. G₂ phase	c. Final preparation for mitosis
4. Mitosis	d. Division of the nucleus
5. Cytokinesis	e. Division of the cytoplasm

True/False:

• Mitosis produces two identical daughter cells. (____)
• The G₀ phase is a resting phase where cells do not divide. (____)
• Cytokinesis happens before mitosis. (____)

Label the Diagram:

Draw a diagram of a cell in mitosis and label the following parts:

• Chromosomes
• Spindle fibers
• Centrioles
• Nuclear membrane

Short Questions:

1. What is the purpose of the cell cycle?
2. What happens during the G₂ phase?
3. Which phase comes after metaphase in mitosis?
4. Explain the difference between cytokinesis in plant and animal cells.

Discussion Question:

Why is it important for the cell cycle to be regulated? What might happen if cell division goes unchecked?

Complete and submit by Friday!