Plants are made up of microscopic cells. Inside each cell, various tiny organelles are at work, helping to keep the plant living and growing. To remember what is inside a plant cell, it helps if you make a three-dimensional model. Part of the joy of a project like this is finding stuff around the house to stand for different parts of the cell. You don't have to follow the exact recipe given here. Use it as a guide to make your own original creation.
Study a diagram of a plant cell, to gain a clear idea of its different parts. You could use an image from a text book, or view a plant cell diagram from BBC Bitesize (see Resources).
Choose a suitable plastic container to represent the rigid walls of the plant cell. A box or tray used to package supermarket fruit or vegetables is a good choice.
Fill a small, clear plastic bag with water. This represents the sap-filled vacuole that sits inside the plant cell. Tie the bag tightly to stop the water leaking out. Place the bag inside the container.
Put a round black pebble inside the container, to represent the cell's nucleus. Roll eight to twelve marble-sized lumps of green modelling clay into balls. They represent the chloroplasts. Flatten your chloroplasts a little, into long oval shapes. Scatter them into the container.
Add material to represent any other organelles shown on your cell diagram. The cell wall, vacuole, nucleus and chloroplasts are the main organelles, but you might see others in more complex diagrams. Model these shapes using string, paperclips, card, seeds, or pasta. You'll find a more complex cell diagram in the Resources section of this article.
Compare your model with the cell diagram. Check the things you've added to your container are a suitable size. Is the nucleus too big or too small when you compare it to the size of the cell, for instance? Swap bits and pieces around until you're satisfied with the size and position of everything in the container.
Put powdered gelatine into a measuring jug. Add hot water and stir with a spoon, following the instructions on the gelatine pack. Let the mixture cool a little, then fill the plastic container to the brim with it. The gelatine will set to represent the cell's rubbery, transparent cytoplasm.
Cover the plastic container tightly with clingfilm. This will keep everything in place and also represent the cell's membrane. Write labels, naming the cell's various parts. For example, "cell wall -- rigid in plants," or "chloroplast -- absorbs light for photosynthesis." Stick your labels to the correct places on the clingfilm.
Take care when using hot water to make up the gelatine mixture.
Tips and warnings
- Take care when using hot water to make up the gelatine mixture.