A cell is the 'building block' from which all living things are made: a daisy, a cat, and a human. Plant and animal cells are structured similarly, but not identically: there are common parts – membrane, cytoplasm, nucleus, mitochondria – and there are parts found only in one or the other. On this page, you'll find diagrams of plant and animal cell structures, a table of organelles and their functions, the main differences – and a trainer to test yourself immediately.
What is a cell and what does it consist of
A cell is the smallest unit of an organism that is alive on its own: it feeds, breathes, grows, and divides. You can only see a cell under a microscope: most cells are 5–10 times thinner than a human hair.
Any cell – both plant and animal – is structured according to the same plan. On the outside, it is enclosed by a thin cell membrane. Inside is a semi-liquid cytoplasm, in which the nucleus and organelles float – permanent parts of the cell, each with its own job.
It's helpful to imagine a cell as a small city: the nucleus is the city hall with documents, mitochondria are power plants, ribosomes are protein assembly factories, the ER is the roads, the Golgi apparatus is the warehouse with packaging, and the membrane is the border with guards who decide who to let in. The difference between a plant and an animal cell is in which 'buildings' are present in this city and which are not.
Structure of a plant cell
The main feature of a plant cell is immediately visible: on top of the membrane, it has a dense cell wall made of cellulose. It is this wall that holds its shape, which is why under a microscope, cells of a leaf or onion epidermis look like neat bricks tightly fitted together.
The second identifying mark is chloroplasts: green bodies with chlorophyll where photosynthesis occurs. The third is one large vacuole in the center: it is filled with cell sap and expands the cell from the inside so strongly that it pushes the cytoplasm and nucleus to the wall. It is thanks to vacuoles that leaves are firm, and the plant wilts without watering.
Structure of an animal cell
An animal cell is simpler on the outside: it lacks a cell wall, having only a soft membrane. Therefore, such a cell is round and can change its shape – a white blood cell in our blood can even crawl by extending pseudopods.
Animal cells lack chloroplasts: animals cannot create organic substances from air and water and obtain them through food. However, lysosomes are well visible – 'stomach' vesicles that digest ingested particles, and the centrosome with centrioles, which participates in cell division and forms spindle fibers. But there is no large central vacuole: only small temporary vesicles are found.
Cell organelles and their functions
It's easiest to remember cell parts not as a list of names, but as 'organelle – what it does' pairs. Tests most often ask about function, not appearance.
| Cell part | What it does |
|---|---|
| Cell membrane | Separates the cell from the external environment and decides what to let in and what to let out |
| Cell wall | A dense outer layer made of cellulose: protects and maintains a constant shape. Only in plants |
| Cytoplasm | Semi-liquid internal environment: connects all cell parts, where reactions occur and substances move |
| Nucleus | The main control center: stores hereditary information in chromosomes and directs cell activity |
| Mitochondria | 'Energy stations': cell respiration occurs here, and energy is stored as ATP |
| Ribosomes | The smallest organelles without a membrane: assemble proteins |
| ER | Endoplasmic reticulum – a system of tubules for substance transport. Ribosomes are attached to the rough ER |
| Golgi apparatus | 'Warehouse and packaging': stores substances, packages them into vesicles, and exports them from the cell |
| Lysosomes | Vesicles with enzymes: digest particles and worn-out cell parts. Particularly noticeable in animal cells |
| Vacuole | A vesicle with cell sap. In plants, it is single and large: stores water and substances, expands the cell from within |
| Plastids (chloroplasts) | Only in plants. Photosynthesis occurs in green chloroplasts with chlorophyll |
| Centrosome (centrioles) | Involved in division: pulls chromosomes to opposite poles of the cell. Higher plants lack centrioles |
Difference between plant and animal cell
These cells have more in common than differences: both have a membrane, cytoplasm, nucleus with chromosomes, mitochondria, ribosomes, ER, and Golgi apparatus. Therefore, it's logical to first mention the commonalities and then list the differences. In short, the main points: only plants have a cell wall, plastids, and a large vacuole, while animals have a centrosome with centrioles and well-developed lysosomes.
| Feature | Plant cell | Animal cell |
|---|---|---|
| Cell wall | present, made of cellulose | absent, only a membrane |
| Plastids, including chloroplasts | present | absent |
| Vacuoles | one large, with cell sap | small and temporary, or absent altogether |
| Centrosome with centrioles | in higher plants, absent | present |
| Lysosomes | almost undeveloped: their function is performed by the vacuole | well-developed |
| Storage substance | starch | glycogen |
| Cell shape | constant, usually rectangular | round, can change |
| Nutrition | produces its own organic substances in light | obtains ready-made organic substances from food |
Task breakdown
Example 1. How to determine from a diagram whether a cell is plant or animal
Task: Here is a diagram of a cell. Determine if it is a plant or animal cell.
Step 1. Look at the boundary. If a thick, rigid layer is visible on the outside, and the cell resembles a brick with straight sides – this is a cell wall, meaning it's a plant.
Step 2. Look for green bodies. If there are chloroplasts – it's definitely a plant cell.
Step 3. Look at the vacuole. A single huge bubble in the center that has pushed the nucleus to the edge – again, it's a plant.
Step 4. If none of these are present, and the cell is round with only a membrane and small vesicles – you are looking at an animal cell.
Conclusion: The three main markers of a plant are the wall, chloroplasts, and a large vacuole. Even one of them is enough.
Example 2. Why is a leaf green, but a root is white
Question: Both the leaf and the root are parts of the same plant. Why are they different colors?
Explanation. Color is provided by plastids, and there are three types. Leaf cells have many green chloroplasts – they need light for photosynthesis. There is no light in root cells, and chloroplasts are useless there: instead, there are colorless leucoplasts where starch is stored. In petals and ripe fruits, chromoplasts are active – they provide red, orange, and yellow colors.
Answer: Chloroplasts are not present in every plant cell, only where there is light.
Example 3. Find the errors in the description
Task: 'In an animal cell, the cell wall protects the contents, and chloroplasts provide it with energy.' Find the errors and correct them.
Error 1. An animal cell lacks a cell wall – its contents are enclosed only by a membrane.
Error 2. Animals also lack chloroplasts, and it is not they, but mitochondria, that provide the cell with energy. Chloroplasts do not 'provide energy' at all: they create organic matter in the light.
Correct version: 'In an animal cell, the contents are enclosed by a cell membrane, and mitochondria provide the cell with energy.'
Common mistakes
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Confusing the cell wall and the cell membrane.
These are different layers. The membrane is present in any cell: it is thin, soft, and selectively permeable. The cell wall lies outside the membrane, it is dense, made of cellulose, and is found only in plants (as well as in fungi and bacteria, but there it is made of different substances).
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Assuming plants do not respire and therefore lack mitochondria.
Plant cells also have mitochondria: plants respire around the clock, just like animals. It's just that during the day, photosynthesis is more active than respiration, making it seem like the plant only releases oxygen.
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Thinking that chloroplasts are present in every plant cell.
Chloroplasts are found where light reaches – primarily in leaf and green stem cells. They are absent in root cells: these have other plastids – colorless leucoplasts storing starch.
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Considering the vacuole as an empty space inside the cell.
The vacuole is filled with cell sap – water with dissolved sugars, salts, and pigments. It stores substances and expands the cell from within, which is why leaves remain firm.
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Stating that animal cells have no vacuoles at all.
More accurately: animal cells lack a large central vacuole with cell sap. Small temporary vacuoles are found – for example, digestive and contractile vacuoles in unicellular animals.
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Calling the nucleus the only organelle without which a cell cannot exist.
The nucleus is indeed central to plant and animal cells, but there are also cells without a defined nucleus – these are bacteria. And plants and animals themselves have anucleated cells, such as mature human red blood cells.
Questions and answers
How does a plant cell differ from an animal cell?
A plant cell has a dense cell wall made of cellulose, plastids (including green chloroplasts), and one large vacuole with cell sap. An animal cell lacks all of these but has a centrosome with centrioles and well-developed lysosomes. Plants produce their own organic substances in light, while animals obtain them from food.
What do plant and animal cells have in common?
A common structural plan: cell membrane, cytoplasm, nucleus with chromosomes, mitochondria, ribosomes, endoplasmic reticulum, and Golgi apparatus. Both cells feed, respire, grow, and divide. Therefore, both plants and animals are classified as eukaryotic organisms.
Which organelles are found only in plant cells?
Plastids – chloroplasts (green, for photosynthesis), chromoplasts (colored, in petals and fruits), and leucoplasts (colorless, store starch). Additionally, only plants have a cell wall made of cellulose and a large central vacuole.
Which organelles are characteristic only of animal cells?
The centrosome with centrioles – higher plants lack it. Lysosomes are also considered a distinct feature of animal cells: in plants, their function is largely performed by the vacuole. The storage substance in animals is also specific – glycogen, not starch.
What is the main part of the cell and why?
The nucleus is considered the main part: it stores hereditary information in chromosomes and controls protein synthesis and cell division. However, a cell cannot survive without a membrane, cytoplasm, and mitochondria – it functions as a unified system.
Do fungi and bacteria have cell walls?
Yes, but they are made of different substances. Plant cell walls are made of cellulose, fungal cell walls are made of chitin, and bacterial cell walls are made of peptidoglycan. Therefore, in an answer, it's important to specify not just 'cell wall' but 'cell wall made of cellulose' – this is specifically a plant characteristic.
