A living thing that is too small to see with the unaided eye.

A type of microscope that uses visible light and a system of lenses to generate magnified images of small objects.

A series of questions about the features of an organism that help us to identify it.

A coloured liquid put onto a specimen so that the cells and their structures can be more easily seen with a light microscope.

Light microscopy: observing and identifying microorganisms

Biology

Non-specific defences of the human body against pathogens

Responses of the human immune system to specific pathogens

Immunity and vaccination

Evaluating the global use of vaccination

Plant defences, and identifying plant diseases

Pupils will learn about the use of antibiotics against pathogens, and the development of new drugs and novel treatments for disease.

Pupils learned about non-communicable diseases in humans, including cardiovascular diseases and cancer; and about communicable diseases in humans and plant caused by pathogens including bacteria, viruses, fungi and protists.

This unit explores the body's defences and immune response against pathogens, disease prevention, and vaccines. It covers plant defence responses, and disease detection, and evaluates scientific applications, considering personal, social, economic, and environmental implications.

Defences against pathogens, the human immune system and vaccination

Physical activity and equipment requiring safe use

Eyepiece lens: viewing lens with ×10 magnification.

Objective lenses: three lenses with different magnifications.

Light source: illuminates the specimen so that it can be observed.

Coarse focus wheel: for adjusting the focus in larger increments.

Fine focus wheel: for adjusting the focus in smaller increments.

Match the part of the microscope to its description.

Turn the objective lenses (b) to the lens with the lowest magnification.

Place the slide on the stage (c) under the clips.

Looking from the side, turn the coarse focus wheel (e) to move the stage up.

Turn the coarse focus wheel (e) to move the stage away from the lens and focus.

Turn the fine focus wheel (f) to make the image as sharp and clear as possible.

Put these steps in order to explain how a light microscope is set up.

How can you increase the magnification of a light microscope?

What can we use to make living material easier to see under a microscope?

We can use a {{}} to identify types of bacteria.

They are most likely gram-positive bacteria.

They are most likely gram-negative bacteria.

The image below shows bacteria growing on an agar plate containing penicillin. Penicillin works best on gram-positive bacteria. What can we conclude about the bacteria growing on the plate?

What do we call a series of questions used to help identify organisms?

Which part of the microscope is labelled E?

True or false? Bacteria are multicellular prokaryotes.

Which type of drug is a doctor likely to prescribe to a patient with a bacterial infection?

Which part of the microscope would you use to bring your specimen into focus?

Place the slice of onion on the glass slide.

Put these steps in order to explain how to make a temporary mount of onion tissue.

Light microscopy: observing and identifying microorganisms

Lesson outcome

Content guidance