2. Plant vs Animal Cells Describe the differences between plant and animal cells Identify organelles under the electron microscope

Microscopes Light microscope – useful magnification up to 1500x – any higher magnification gives blurred images. Can distinguish between objects as small as 200nm. Electron microscopes – 1930’s – uses a beam of electrons and give resolutions of about 0.2 nm (1000x better than the light microscope) and magnifications of up to 500 000x Why do we not use electron microscopes at school?

How they work.

Electron microscopes… 2 types – Transmission electron microscopes send electrons through a very thin sample and can see inside cells. We use these to study cell organelles. Scanning electron microscope sends electrons onto the surface of a sample where they bounce off and are detected by a screen. These are useful for making 3D images of the outside of organelles or cells.

Which microscope? TEM, SEM or light?

Plant vs Animal Cells – complete the table Cell Membrane Cell Wall Nucleus Endoplasmic Reticulum Mitochondria Chloroplasts Golgi Body Lysosomes Centrioles Vacuoles

Can you identify any organelles in this electron microscope pictures?

Plant or animal cell?

What is the difference between these two? Which is from a plant cell?

Close up of part of an adrenal cell Close up of part of an adrenal cell. What do you think the dark shapes are?

Summary: Plant and animal cells can be viewed best using the ___________________ microscope as this can mangnify up to ________________ and distinguish between objects ____________ nm in size. Plant cells are different from animal cells because they contain ______________, _____________ and a __________________. They are generally ___________ in size than animal cells.