2. Leeuwenhoek made a simple microscope (mid 1600’s) magnified 270X Early microscope lenses made images larger but the image was not clear

3. Leeuwenhoek's Microscope A) a screw for adjusting the height of the object being examined B) a metal plate serving as the body C) a skewer to impale the object and rotate it D) the lens itself, which was spherical

4. CELL THEORY A theory resulting from many scientists’ observations & conclusions Sch wan n Sch leid en Virc how

5. CELL THEORY 1. The basic unit of life is the cell. (Hooke) In 1665, an English scientist named Robert Hooke made an improved microscope and viewed thin slices of cork viewing plant cell walls Hooke named what he saw "cells"

6. CELL THEORY 2. All living things are made of 1 or more cells. Matthias Schleiden (botanist studying plants) Theodore Schwann (zoologist studying animals) stated that all living things were made of cells Schleiden Schwann

7. CELL THEORY 3. All cells divide & come from old cells. (Virchow) Virchow

8. MODERN MICROSCOPES A microscope is simple or compound depending on how many lenses it contains A lens makes an enlarged image & directs light towards you eye

9. A simple microscope has one lens Similar to a magnifying glass Magnification is the change in apparent size produced by a microscope

10. COMPOUND MICROSCOPE A compound microscope has multiple lenses –(eyepiece & objective lenses)

11. STEREOMICROSCOPE creates a 3D image

12. TOTAL MAGNIFICATION Powers of the eyepiece (10X) multiplied by objective lenses determine total magnification.

13. ELECTRON MICROSCOPES More powerful; some can magnify up to 1,000,000X Use a magnetic field in a vacuum to bend beams of electrons Images must be photographed or produced electronically

14. Scanning Electron Microscope (SEM) Electron microscope image of a spider produces realistic 3D image only the surface of specimen can be observed Electron microscope image of a fly foot

15. Transmission Electron Microscope (TEM) produces 2D image of thinly sliced specimen detailed cell parts (only inside a cell) can be observed

16. Scanning Tunneling Microscope (STM) able to show arrangement of atoms

17. Cell Structure & Function http://koning.ecsu.ctstateu.edu/cell/cell.html

18. Definition of Cell A cell is the smallest unit that is capable of performing life functions.

19. Examples of Cells Amoeba proteus Plant Stem Red Blood Cell Nerve Cell Bacteria

20. Two Types of Cells Prokaryotic Eukaryotic

21. Prokaryotic Do not have structures surrounded by membranes Few internal structures One-celled organisms, Bacteria http://library.thinkquest.org/C004535/prokaryotic_cells.html

22. Eukaryotic Contain organelles surrounded by membranes Most living organisms PlantAnimal http://library.thinkquest.org/C004535/eukaryotic_cells.html

23. “Typical” Animal Cell http://web.jjay.cuny.edu /~ acarpi/NSC/images/cell.gif

24. http://waynesword.palomar.edu/images/plant3.gif “Typical” Plant Cell

25. Cell Parts Organelles

26. Surrounding the Cell

27. Cell Membrane Outer membrane of cell that controls movement in and out of the cell Double layer http://library.thinkquest.org/12413/structures.html

28. Cell Wall Most commonly found in plant cells & bacteria Supports & protects cells http://library.thinkquest.org/12413/structures.html

29. Inside the Cell

30. Nucleus Directs cell activities Separated from cytoplasm by nuclear membrane Contains genetic material - DNA

31. Nuclear Membrane Surrounds nucleus Made of two layers Openings allow material to enter and leave nucleus http://library.thinkquest.org/12413/structures.html

32. Chromosomes In nucleus Made of DNA Contain instructions for traits & characteristics http://library.thinkquest.org/12413/structures.html

33. Nucleolus Inside nucleus Contains RNA to build proteins http://library.thinkquest.org/12413/structures.html

34. Cytoplasm Gel-like mixture Surrounded by cell membrane Contains hereditary material

35. Endoplasmic Reticulum Moves materials around in cell Smooth type: lacks ribosomes Rough type (pictured): ribosomes embedded in surface http://library.thinkquest.org/12413/structures.html

36. Ribosomes Each cell contains thousands Make proteins Found on ER & floating throughout the cell http://library.thinkquest.org/12413/structures.html

37. Mitochondria Produces energy through chemical reactions – breaking down fats & carbohydrates Controls level of water and other materials in cell Recycles and decomposes proteins, fats, and carbohydrates http://library.thinkquest.org/12413/structures.html

38. Golgi Bodies Protein 'packaging plant' Move materials within the cell Move materials out of the cell http://library.thinkquest.org/12413/structures.html

39. Lysosome Digestive 'plant' for proteins, fats, and carbohydrates Transports undigested material to cell membrane for removal Cell breaks down if lysosome explodes http://library.thinkquest.org/12413/structures.html

40. Vacuoles Membrane-bound sacs for storage, digestion, and waste removal Contains water solution Help plants maintain shape http://library.thinkquest.org/12413/structures.html

41. Chloroplast Usually found in plant cells Contains green chlorophyll Where photosynthesis takes place http://library.thinkquest.org/12413/structures.html