4. The Cell The basic unit of life

5. Can you guess that cell type???

14. Macrophage killing bacteria

15. Nerve Cell

16. Human Cheek Cell

17. Plant (onion) Cells

18. Sperm and Egg Cells

19. Paramecium (single celled organism)

20. Amoeba (single celled organism)

21. Bacteria Cells

22. Cellular Variation Cells come in numerous shapes and sizes. Their shape is usually somehow related to their function. Some organisms like plankton, amoeba and bacteria are composed of a single cell. Bacteria cells do NOT contain a nucleus = prokaryotic Other, more complex organisms, are made of mnay different cells with a nucleus = eukaryotic Humans are made up of about 100 trillion cells!

23. Van Leeuwenhoek the “father of microscopy”

24. Robert Hooke + Cork = “Cells”

25. Times have changed, yet …

26. The Cell Theory 1.All living things are made of cells. 2.Cells are the basic unit of life. 3. All cells come from preexisting cells.

27. How big is a cell?

28. What size are the cells we looked at last class? Actual Size= field of view ÷ estimate of # of specimens that fit across F.O.V