Animal Cell

• Animal cell — cell membrane (no cell wall), nucleus, cytoplasm, mitochondria.
• No chloroplasts — animals cannot photosynthesise.
• Small vacuoles — many or temporary (food vacuoles).
• Observe cheek cells — irregular shape.

1. Shape — often round/irregular (no rigid wall).
2. Cell membrane only — outer boundary flexible.
3. Centrosome — involved in cell division (intro level in animal cells).
4. Energy — food from plants/other animals; mitochondria release energy.
5. Comparison table — plant: wall+chloroplast+large vacuole; animal: none of these.
6. Real world — cheek cell scrape; muscle cells elongated; nerve cells with extensions.

Preparing human cheek cell slide

Step 1 — Clean toothpick, scrape inside cheek gently.
Step 2 — Smear on slide with saline drop.
Step 3 — Methylene blue stain; cover slip.
Step 4 — See irregular cells, dark nucleus, no cell wall or chloroplast.

• Drawing cell wall on animal cell (common exam error).
• Misconception: animal cells have no vacuole (small vacuoles present).
• Confusing cheek cell with onion cell shape (onion rectangular due to wall).
• Using dirty slide — bacteria confuse observation.

• How is animal cell different from plant cell?
• Why do animal cells lack chloroplast?
• Name organelles common to both plant and animal cells.

Open the Practice tab for graded questions on Animal Cell.