Everything for the Cell System test: study cards, the traps to dodge, and a practice quiz at three levels — Foundation, On-Level, and Challenge. Work here, or print it and use a pencil — both count.
A leaf. Smooth and green — nothing on it looks divided into parts.
Everything alive is made of cells — you are built from roughly thirty trillion of them. The nucleus holds the DNA and directs the cell; the membrane decides what gets in and out; and the organelles inside each do one job.
What people get wrong
⚠️People often think…
Plants do photosynthesis, so they do not do cellular respiration.
They do both, all the time. Photosynthesis stores energy in sugar; respiration is what releases it as ATP, and every plant cell needs ATP day and night. One fills the store, the other spends from it.
Plants do both. Every cell needs ATP.
⚠️People often think…
Cellular respiration is a science word for breathing.
Breathing moves air into and out of lungs. Cellular respiration happens inside every cell, in the mitochondria, breaking sugar down to release energy. Breathing supplies one ingredient; it is not the same process.
Lungs move air. Cells break down sugar.
⚠️People often think…
Animal cells have mitochondria; plant cells have chloroplasts instead.
Plant cells have BOTH. They need chloroplasts to make sugar and mitochondria to spend it. What animal cells lack is chloroplasts — and a cell wall, and a large central vacuole.
Plant cells have both. Animal cells lack chloroplasts.
⚠️People often think…
Osmosis and diffusion are two words for the same thing.
Diffusion is any particle spreading from crowded to less crowded. Osmosis is specifically WATER crossing a membrane toward the side with more dissolved material. Osmosis is one case of diffusion, not a synonym.
Osmosis is water across a membrane.
Find the part, name the job
1Watch one
A plant is kept in the dark for a week. What happens inside its cells?
No light means the chloroplasts stop making sugar.
But the mitochondria keep running — every cell still needs ATP.
So the plant keeps spending stored sugar with nothing refilling it.
The store runs out and the plant starves. Both processes were running the whole time. ✓
2Do one with me
Fill in the parts and their jobs.
The part that holds the DNA is the
The part where respiration happens is the
Plant cells have chloroplasts AND
💬One sentence, then you move on
Why do plants need mitochondria if they make their own sugar?
3Try one
A cell is placed in salty water. Which way does the water move?
I want a hint first
Water follows the dissolved stuff. The salt was added to the outside.
💬Last one — then you're done here
Why is osmosis a special case rather than a synonym for diffusion?
Where this goes
Where this lives
Why a cut needs protein and calories to heal, why salting a slug kills it, why wilted lettuce crisps up in cold water.
What this feeds
Next unit is body systems — cells organized into tissues, organs and systems.
Name one place you have seen water move into or out of something.
One card at a time — tap “Show me” to check yourself, then Next. Start at Foundation; when those feel easy, climb.
Helpful Hints
🧱 Cell theory — three sentences, easy points
1. All living things are made of cells. 2. The cell is the basic unit of life. 3. All cells come from existing cells.
All living · Basic unit · Cells from cells
🔁 The two big equations are mirror images
Photosynthesis: CO₂ + water + light → sugar + oxygen. Cellular respiration: sugar + oxygen → CO₂ + water + energy. One builds sugar, the other burns it.
Flip the arrow.
⚠️ Traps the test loves
Plants DO cellular respiration — every living cell needs to release energy.
Cellular respiration ≠ breathing. It happens inside cells, in mitochondria.
Both plant AND animal cells have mitochondria.
Osmosis is only about water — diffusion is the general word.
Cells divide instead of growing forever — a giant cell can’t move materials fast enough.
🏭 Organelle jobs — think of a factory
Nucleus = the main office (holds DNA).
Mitochondria = power plant (releases energy).
Chloroplast = solar panel + kitchen (plants only).
Cell membrane = security gate (controls what enters/exits).
Cell wall = stiff outer wall (plants only).
🎯 How the test will ask
Expect a labeled cell diagram — know organelles by shape and location.
Mitosis questions love ORDER: PMAT — Please Make A Taco.
Transport hinges on one word: passive = no energy, active = energy needed.
✅ Before the test, can you…
Say all three parts of cell theory?
Name 3 differences between plant and animal cells?
Put PMAT in order and say what each phase does?
Write both equations (photosynthesis and respiration)?
Explain WHY cells divide instead of growing huge?
Term
Meaning in 10 words or less
Cell theory
All life is cells; cells come from cells.
Organelle
A tiny structure with a job inside a cell.
Nucleus
Control center holding the DNA.
Mitochondria
Releases energy from sugar.
Chloroplast
Captures sunlight to make food (plants).
Cell membrane
Gate controlling what enters and leaves.
Cell wall
Stiff outer support layer (plants, fungi, bacteria).
Diffusion
Particles spread from crowded to less crowded.
Osmosis
Diffusion of water through a membrane.
Active transport
Movement that costs the cell energy.
Mitosis
One cell divides into two identical cells.
Photosynthesis
Making sugar from CO₂, water, and light.
Cellular respiration
Releasing energy from sugar using oxygen.
Chlorophyll
Green pigment that captures light energy.
Pick your level
Look back at anything you missed — the hint that appeared is exactly what to reread tonight.
How sure did you feel?
Workshop
Work like a cell biologist: name the parts on a plant cell, decide which parts an animal cell has too, put the cell cycle in order, then explain the size limit every cell lives under.
Meet the cell
Tap a part. The name comes after the shape.
Same rule as the microscope: look first. The plant cell is the full machine. Flip to animal to see what drops away.
A part
Tap the wall, the gate, the green oval, the bean, the store-room, or the round center.
Names stay off until you ask. Shape first.
Your practice never leaves this device. There is no account and no sign-in. Your work is saved in this browser only, and you can erase it whenever you want.
Your practice record — saved on this device
This is your record of the module on screen — it stays here and goes nowhere. Independent means you got it right on the first tap; supported means you got it after the explain-and-retry, or marked ‘I had it’ on a revealed answer. Both count, and neither is a grade. If your teacher asks, copy the row or show them this screen.
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The answer key is for a teacher: it prints only from here, for the unit on screen. Print the study packet prints the study pages and a blank quiz — never the answers.