AP BIOLOGY POGIL - The Cell Cycle Questions with Answers - AP ... - Free Printable

Let's go through the POGIL worksheet titled *"The Cell Cycle"* and solve each question step by step, based on Model 1 - The cell cycle diagram.

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Model 1 - The Cell Cycle Diagram Overview

The diagram shows a circular process with four labeled phases:

- G₁ (Gap 1) – Cell growth
- S (Synthesis) – DNA replication
- G₂ (Gap 2) – Preparation for division
- M (Mitosis) – Cell division (including cytokinesis)

The cycle starts at the starred cell and proceeds clockwise.

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Question 1: How many phases are in the cell cycle as shown in the diagram in Model 1?

✔ Answer: Four

Explanation:
The diagram clearly labels four distinct phases:
1. G₁ (Gap 1)
2. S (Synthesis)
3. G₂ (Gap 2)
4. M (Mitosis)

These four phases make up the complete eukaryotic cell cycle.

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Question 2: Starting at the starred cell, what is the order of the stages of a cell's life?

We need to follow the arrows starting from the starred cell.

Looking at the diagram:
- The star is placed on a cell in G₁ phase.
- From there, the cycle moves clockwise:
1. G₁ →
2. S →
3. G₂ →
4. M → back to G₁ (new daughter cells)

So, the correct order is:

✔ G₁ → S → G₂ → M

Answer:
1. G₁
2. S
3. G₂
4. M

(Note: The worksheet says "1' 2'" — this might be a typo or formatting issue. We interpret it as asking for the sequence.)

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Question 3: During which phase does the size of the cell increase?

✔ Answer: G₁ (Gap 1)

Explanation:
During G₁ phase, the cell grows in size, synthesizes proteins, and carries out normal metabolic activities in preparation for DNA replication. This is the primary period of cell growth before DNA synthesis.

> Note: Some growth may occur in G₂, but G₁ is the main phase for cell enlargement.

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Question 4: During which phase does the number of cells increase?

✔ Answer: M (Mitosis)

Explanation:
The M phase includes mitosis (nuclear division) and cytokinesis (cytoplasmic division). This is when one cell divides into two daughter cells. Therefore, the number of cells increases during this phase.

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Question 5: Considering your answers to Questions 3 and 4, identify two ways that the growth of an organism can be accomplished through the events of the cell cycle.

From Question 3: Growth occurs via increase in cell size → happens in G₁ phase
From Question 4: Growth occurs via increase in cell number → happens in M phase

✔ Answer:
Growth can happen when:
1. Cells increase in size (during G₁ phase), and
2. The number of cells increases (during M phase).

This means organisms grow both by making larger cells and by producing more cells.

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✔ Final Answers Summary:

| Question | Answer |
|--------|--------|
| 1 | Four |
| 2 | G₁ → S → G₂ → M |
| 3 | G₁ (Gap 1) |
| 4 | M (Mitosis) |
| 5 | Growth occurs by increasing cell size (G₁) and increasing cell number (M) |

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🧠 Key Concept Recap:

The cell cycle ensures controlled growth and reproduction of cells. It allows organisms to:
- Grow (via cell growth in G₁),
- Repair tissues (via cell division),
- Reproduce (in multicellular organisms),
- Maintain homeostasis.

Understanding these phases helps explain how organisms develop, heal, and function.

Let me know if you'd like a visual summary or explanation of each phase!