Vaccines work by introducing dead or weakened invaders into the body. The body will develop antibodies against the weak invaders. If a strong invader of the same kind enters the body later, the antibodies can be used to destroy it before it takes over any cells. Using diagrams, show how a vaccine might protect the body from invaders.
You will need to draw a diagram that shows some disease causing organism entering the body. These do not have to be the actual shape. You could draw triangles and state in the diagram's key that they are viruses or bacteria, the choice is yours.
Next you would need to show another shape, perhaps a square coming into contact with the invaders, the triangles. The squares should be labelled macrophages.
The next step would be to show the macrophage presenting the invader to a B-cell. This could be a circle. As a result the B-cell produces antibodies. These could be Y-shaped as antibodies are often represented with this shape. Show these circulating through the body.
B-cells also produce memory cells which are the ones that respond to the same or similar invader. For example, after being stimulated by vaccination they would react if the person was infected by the actual disease-causing organism. I would draw these as circles but smaller than the ones used for the B-cells.
It would also make your diagram stand out more if as well as using the shapes I have recommened that you colour in each shape. Remember to use the same colour for the same thing in the diagram. For example, the "invaders" the triangles could be red.
Ensure that your diagram has a key. This will tell whoever looks at our diagram what each coloured shapes represents.