← Biology XI
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Class XI · Chapter 4 · Walkthrough

The Cell — a tour of the organelles

01 · The cell

A cell is a tiny factory

A eukaryotic cell is bounded by a membrane, filled with cytoplasm, and packed with organelles — each a specialised "machine". Press ▶ Play to highlight each organelle and read what it does.

02 · The control & the workers

Nucleus, mitochondria, ribosomes

The nucleus stores the DNA and runs the cell. Mitochondria release energy as ATP by respiration. Ribosomes read the instructions and build proteins — on the rough ER, then packaged by the Golgi.

03 · The boundary

The membrane keeps order

The thin cell membrane is selectively permeable: it lets useful substances in, keeps wastes moving out, and holds everything together. Animal cells have only this membrane on the outside.

04 · Plant extras

What makes a plant cell different

A plant cell has everything an animal cell has, plus a rigid cell wall (cellulose, for support), chloroplasts (for photosynthesis), and a large central vacuole (keeps the cell firm/turgid). Switch the tab to compare.

05 · Animal vs plant

Telling them apart

In the exam: a boxy cell with a wall, green chloroplasts and a big vacuole is a plant cell. A rounded cell with just a membrane and no chloroplasts is an animal cell. Both share nucleus, mitochondria, ribosomes, ER and Golgi.

🔬 Cell exploreranimal cell
Press ▶ Play to highlight each organelle and read its job.