Can you guess what these are pictures of

Lesson 2 - Microscopy Learning Objectives: 1. Compare and contrast light microscopes and electron

Video: Microscopes • https: //www. brainpop. com/technology/scienceandindustry/microsc opes/ • Watch the video and answer

Microscopes • The images from the starter were taken using an electron microscope. •

Light Microscope • Lenses – magnification • Focusing wheels – moves the stage up

Practical: Observe onion and cheek cells • You will now prepare a slide of

Demo: Preparing an Onion Skin Slide • https: //www. youtube. com/watch? v=e. D 1

Different Microscopes have different Magnification and Resolution •

Electron Microscopes • Electron microscopes have higher magnification and better resolution. • This means

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Can you guess what these are pictures of?

Butterfly proboscis

Hair (from a hare)

Pollen grains

Salt grains

Snowflakes

Fly’s Eye

Lesson 2 - Microscopy Learning Objectives: 1. Compare and contrast light microscopes and electron microscopes. 2. Explain how the invention of electron microscopes was impacted the study of cells. 3. Carry out magnification calculations. 4. Practical skills: Be able to prepare a slide and use a microscope.

Video: Microscopes • https: //www. brainpop. com/technology/scienceandindustry/microsc opes/ • Watch the video and answer the following questions. • What are the different types of microscopes? • Give a BRIEF description of how they work.

Microscopes • The images from the starter were taken using an electron microscope. • Electron microscopes use a beam of electrons to capture an image. • Electron microscopes can magnify images up to 10, 000 X. • Light microscopes are simpler and use lenses to focus visible light and magnify an image. • Light microscopes can magnify images up to 2, 000 X.

Light Microscope • Lenses – magnification • Focusing wheels – moves the stage up and down to focus the image • Stage – holds the slide • Slide – transparent glass to hold the specimen • Light source – to provide light to form a magnified image Eyepiece lens Fine focusing wheel Coarse focusing wheel Objective lens Slide Light Stage source

Practical: Observe onion and cheek cells • You will now prepare a slide of onion skin tissue and cheek cells to observe through the microscope. • Watch the demo of how to prepare a slide. • Follow the instructions carefully and make detailed drawings of the cells you observe. • Required practical skills: Use a light microscope to observe, draw and label a selection of plant and animal cells. A scale magnification must be included.

Demo: Preparing an Onion Skin Slide • https: //www. youtube. com/watch? v=e. D 1 Cdf. Rycqs

Different Microscopes have different Magnification and Resolution •

Electron Microscopes • Electron microscopes have higher magnification and better resolution. • This means that it can be used to study cells in more detail. • This has enabled biologists to see and understand many more subcellular structures (like mitochondria).