1 / 6

Cells, microscopes and creepy crawlies

Cells, microscopes and creepy crawlies. And all the other things you can’t see!. How small are they really?. E. coli: 2-3 μ m. Influenza virus: 0.130 μ m OR 130 nm. 1000 μ m!!!. Let’s have a closer look!!!. Onion cell: 250-400 μ m. Red Blood cell: 8 μ m.

kirra
Télécharger la présentation

Cells, microscopes and creepy crawlies

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Cells, microscopes and creepy crawlies And all the other things you can’t see!

  2. How small are they really? E. coli: 2-3 μm Influenza virus: 0.130μm OR 130 nm 1000 μm!!! Let’s have a closer look!!! Onion cell: 250-400 μm Red Blood cell: 8 μm

  3. Field of view • When you look in a microscope the circle of light that you see is called the ‘field of view’ • But how do we know how small a cell/specimen really is? • It depends on the magnification • As you increase the magnification the field of view decreases

  4. Measuring a cell! 1,600 μm Field diameter ÷ no. cells ÷ 3 1,600 μm 1000 μm!!! ≈ 533 μm

  5. Measuring a cell! Field diameter ÷ no. cells 4,000 μm 1,600 μm 400 μm Low 4,000 μm ÷ 2 ≈ 2,000 μm ≈ 800 μm 1,600 μm ÷ 2 Medium ≈ 200 μm 400 μm ÷ 2 High

  6. Measuring your own specimens! • We’re going to look at a few specimen • Draw what you see • Write down the magnification • Low = 4 × 10, Medium = 10 × 10, High = 40 × 10 • Guess how many of them you could fit side by side • Use the formula to work out how long / wide your specimen are! • Then we’ll come back to our tables to discuss what we found

More Related