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Cell Explorer

Zoom inside the cell: eukaryotic vs prokaryotic, every organelle and its job, and how cells specialise for a purpose.

⏱️ 10 min 🎯 14 activities Teachers Not yet rated Students Not yet rated

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What you'll cover

Cell Explorer 🔬

Every living thing is built from **cells**. Zoom in and you find tiny structures — each with a job — packed inside. This mission: tell the two cell *types* apart, name every structure and what it does, and see how cells become **specialised**. Suit up.

Two types of cell 🦠

All cells fall into two types: • **Eukaryotic** cells have a **nucleus** holding their genetic material. Animal and plant cells are eukaryotic. • **Prokaryotic** cells (**bacteria**) are much **smaller** and have **no nucleus** — their DNA is a single loop floating free in the cytoplasm, sometimes with extra small rings called **plasmids**.

Spot the difference

What is the key difference between a **prokaryotic** and a **eukaryotic** cell?

  • A prokaryotic cell has no nucleus
  • A prokaryotic cell has no DNA at all
  • A prokaryotic cell is much bigger
  • Only prokaryotic cells can be plant cells

Structures in every cell 🧫

Animal (and plant) cells share these sub-cellular structures: • **Nucleus** — controls the cell and holds the genetic material (DNA). • **Cytoplasm** — jelly where most chemical reactions happen. • **Cell membrane** — controls what enters and leaves the cell. • **Mitochondria** — site of **aerobic respiration**, releasing energy. • **Ribosomes** — site of **protein synthesis**.

Find the control centre

An interactive activity.

Match the job

  • Nucleus
  • Cell membrane
  • Mitochondria
  • Ribosomes
  • Cytoplasm
  • Controls the cell; holds the DNA
  • Controls what enters and leaves
  • Site of aerobic respiration
  • Site of protein synthesis
  • Where most chemical reactions happen

Plant cells have extras 🌿

A plant cell has **everything an animal cell has, plus three more**: • **Cell wall** — made of **cellulose**; strengthens and supports the cell. • **Chloroplasts** — contain **chlorophyll**; the site of **photosynthesis**. • **Permanent vacuole** — filled with **cell sap**; keeps the cell firm (turgid).

Find the food factory

An interactive activity.

Plant-only structures

Pick the THREE structures found in plant cells but NOT in animal cells.

  • Cell wall
  • Chloroplasts
  • Permanent vacuole
  • Nucleus
  • Mitochondria

Cells with a speciality 🧬

Cells aren't all the same. Through **differentiation**, a cell becomes **specialised** — gaining the sub-cellular structures suited to a particular job. In animals, most differentiation happens **early** in development; in plants, many cells keep the ability to differentiate throughout life.

Built for the job

  • Sperm cell
  • Nerve cell
  • Root hair cell
  • Xylem cell
  • Phloem cell
  • A tail to swim to the egg
  • Long, to carry electrical impulses
  • A large surface area to absorb water
  • Hollow tubes that carry water up the plant
  • Tubes that transport dissolved sugars

Name the process

What is **differentiation**?

  • The process by which a cell becomes specialised for its job
  • A cell splitting into two identical cells
  • A cell breaking down and dying
  • A cell simply getting bigger

Why that shape?

A root hair cell has a long, thin projection sticking out into the soil. How does that help it?

  • It gives a large surface area to absorb more water and mineral ions
  • It catches more sunlight for photosynthesis
  • It lets the cell swim through the soil
  • It carries electrical impulses

In the exam 🎓

Mission complete. Grade-9 habits for cell structure: • **Eukaryotic** = has a nucleus (plant/animal); **prokaryotic** (bacteria) = no nucleus, DNA in a loop. • Know every structure's **function** — and that plant cells add a **cell wall, chloroplasts and a permanent vacuole**. • **Differentiation** makes cells **specialised**; link each specialised cell to how its shape fits its job.