Cell Biology Worksheet: Labeling Cell Parts and Their Functions

Let’s work through this step by step.

This worksheet has two main parts:

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Part 1: Label the cell parts in the diagrams (Animal Cell and Plant Cell)

We need to identify what each numbered part is in both cells.

Animal Cell (Diagram 1):

Looking at a typical animal cell diagram:

- Label 1 points to the large dark circle inside → that’s the Nucleus
- Label 2 points to the outer boundary → that’s the Cell surface membrane (also called plasma membrane)
- Label 3 points to the jelly-like substance filling the cell → that’s the Cytoplasm
- Label 4 points to the small oval structures with lines inside → those are Mitochondria

✔ So for Animal Cell:
1. Nucleus
2. Cell surface membrane
3. Cytoplasm
4. Mitochondria

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Plant Cell (Diagram 2):

Plant cells have extra parts compared to animal cells.

- Label 1 → points to the large dark circle → Nucleus
- Label 2 → points to the thick outer layer → Cell wall
- Label 3 → points to the thin line just inside the cell wall → Cell surface membrane
- Label 4 → points to the green oval structures → Chloroplasts
- Label 5 → points to the small green ovals too → also Chloroplasts? Wait — let’s check again.

Actually, looking closely:

In plant cell diagrams:

- Label 1: Nucleus ✔
- Label 2: Cell wall ✔ (thick outer layer)
- Label 3: Cell surface membrane ✔ (just inside cell wall)
- Label 4: Chloroplast ✔ (green organelles)
- Label 5: Also chloroplast? Or maybe vacuole? No — label 6 points to the big empty space → that’s the Vacuole
- Label 7: Points to mitochondrion (same as in animal cell) → Mitochondria

Wait — let’s reassign based on standard labeling:

Standard plant cell labels:

- 1: Nucleus
- 2: Cell wall
- 3: Cell membrane (surface membrane)
- 4: Chloroplast
- 5: Cytoplasm? But cytoplasm isn’t usually labeled separately like that… Hmm.

Actually, looking at the diagram again:

Label 4 points to a chloroplast.

Label 5 points to another chloroplast? Or perhaps it's pointing to the cytoplasm? But cytoplasm is everywhere.

Wait — label 6 points to the large central vacuole → that’s definitely Vacuole

Label 7 points to a mitochondrion → Mitochondria

So let’s list them clearly:

Plant Cell:

1. Nucleus
2. Cell wall
3. Cell surface membrane
4. Chloroplast
5. Cytoplasm? Or maybe another chloroplast? Actually, label 5 seems to point to a chloroplast too — but we already have label 4. Maybe label 5 is meant to be cytoplasm? But cytoplasm is not typically labeled with an arrow pointing to a specific spot unless specified.

Wait — perhaps label 5 is pointing to the cytoplasm, since it’s between the membrane and organelles.

But in many worksheets, they label:

- 1: Nucleus
- 2: Cell wall
- 3: Cell membrane
- 4: Chloroplast
- 5: Cytoplasm
- 6: Vacuole
- 7: Mitochondria

Yes, that makes sense.

So:

Plant Cell:

1. Nucleus
2. Cell wall
3. Cell surface membrane
4. Chloroplast
5. Cytoplasm
6. Vacuole
7. Mitochondria

✔ Confirmed.

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Part 2: Functions of the Cell Parts

We need to fill in the function (job) for each structure.

Also, shade in green the structures found ONLY in plant cells.

Let’s go one by one:

| Cell Structure | Function (job) | Only in Plant Cells? |
|-----------------------|--------------------------------------------------------------------------------|----------------------|
| Nucleus | Controls the cell’s activities; contains DNA | No |
| Cytoplasm | Jelly-like substance where chemical reactions happen; holds organelles | No |
| Cell surface membrane | Controls what enters and leaves the cell | No |
| Mitochondria | Releases energy from food (respiration) | No |
| Cell wall | Gives plant cell strength and shape; made of cellulose | YES → shade green |
| Chloroplast | Makes food using sunlight (photosynthesis); contains chlorophyll | YES → shade green |
| Vacuole | Stores water, salts, sugars; keeps cell rigid (in plants) | YES → shade green |

Note: Animal cells can have small vacuoles, but the large central vacuole is unique to plant cells. In this context, “Vacuole” refers to the large central one → so yes, only in plant cells.

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Now, compiling all answers:

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Final Answer:

Animal Cell Labels:
1. Nucleus
2. Cell surface membrane
3. Cytoplasm
4. Mitochondria

Plant Cell Labels:
1. Nucleus
2. Cell wall
3. Cell surface membrane
4. Chloroplast
5. Cytoplasm
6. Vacuole
7. Mitochondria

Functions Table:

| Cell Structure | Function (job) |
|-----------------------|--------------------------------------------------------------------------------|
| Nucleus | Controls the cell’s activities; contains genetic material (DNA) |
| Cytoplasm | Where most chemical reactions take place; holds organelles |
| Cell surface membrane | Controls what goes in and out of the cell |
| Mitochondria | Produces energy for the cell by breaking down food |
| Cell wall | Supports and protects the plant cell; gives it shape |
| Chloroplast | Uses sunlight to make food (photosynthesis) |
| Vacuole | Stores water and nutrients; helps keep the plant cell firm |

Structures only in plant cells (shade these green in the table):
- Cell wall
- Chloroplast
- Vacuole

*(Note: In the actual worksheet, you would shade the rows for Cell wall, Chloroplast, and Vacuole in the "Cell Structure" column.)*