1. Microscopes

2. Objectives
Relate advances in microscope technology to discoveries about cells and cell structure
Compare the operation of a compound light microscope with that of an electron miroscope
Identify the main ideas of the cell theory

3. Before Microscopes
Before microscopes people believed that diseases were caused by curses and supernatural spirits.

4. MICROSCOPE
Microscope  tool used to look at small organisms (microorganisms)
MICROSCOPE
“Micro” = small
“Scope” = to look at

5. MICROSCOPES ALLOW US TO SEE CELLS
Cell  basic unit of life

6. Plant cell
Animal cell

7. Kinds of Microscopes 3 Major kinds of microscopes
Simple Light Microscope
Compound Light Microscope
Electron Microscope

8. Simple Light Microscope
Simple Light – 1st type invented (1500’s)
1 Lens
Energy Source = Light
Low Magnification power

9. Compound Light Microscope
2+ Lenses
Energy Source = Sunlight or Electricity
Up to about 1500 x’s actual size

10. Can you find the differences between simple and compound?

11. Magnification lens = 10X objective = 4X (multiply)
TOTAL MAGNIFIATION = (lens) X (objective)
lens = 10X objective = 4X (multiply)
Total Magnification = (10) X (4)
= 40 X’s actual size
What is the total magnification of a microscope with an objective of 10x?

12. Electron Microscopes Electron Microscopes
Light Source = beam of electrons
Magnify up to 500,000 X’s actual size

13. MAJOR DISADVANTAGE : KILLS SPECIMEN
Electron Microscopes
2 kinds of electron microscopes:
SEM TEM
Scanning Electron Microscope
surface
Transmission Electron Microscope
inside
MAJOR DISADVANTAGE : KILLS SPECIMEN

14. Taken by a S.E.M.

15. Can you guess what this is? It was taken by a T.E.M.

16. Carrying a Microscope CAREFULLY!!!! They are expen$ive!!
One hand on ARM
Other hand on BASE

17. Microscope Label Turn to page 1070 in your book
Label your microscope worksheet
Write down vocab on back of paper

18. Important Scientists ONCE UPON A TIME in the mid 1600’s…
Anton van Leeuwenhoek – first microscope (single lens, used light to see object)
Robert Hooke
– named cells
– looked at dead oak bark (cork), saw small chambers like rooms in a monastery
– Coined the term “cell”

19. More Important Scientists
Schleiden – all plants made of cells
Schwann – all animals made of cells
Schwan sounds like swan (an animal)
Brown – some cells contain a “prominent structure” (aka nucleus)
Virchow – Brown’s “structure” (aka nucleus) is responsible for cell division

20. IS AN ORGANELLE A LIVING ORGANISM?
Cell
Cell – basic units of living things
atomsmake up
moleculesmake up
organellesmake up
cells make up 
tissues make up
 organs  make up
organ systems make up
Organisms (LIKE YOU!)
IS AN ORGANELLE A LIVING ORGANISM?

21. The Summary of all these Ideas led to the… Cell Theory
1. All organisms are composed of one or more cells
2. The cell is the basic unit of living organisms
3. All cells come from preexisting cells

22. Quick Project: Cell Theory Foldable
Make a tri-fold in a piece of paper
Label each section with a PART of the cell theory…
Explain each part of the cell theory using a PICTURE…
Be sure to include any important scientists in your drawings where appropriate!
You may use words to explain your picture, but the picture should do “most of the talking,” if you know what I mean…

23. Cells are made up of ORGANELLES
Organelles = specialized structures that have a specific function in the cell

24. 2 Types of Cells 2 kinds of Organelles and 2 kinds of CELLS
Prokaryotic Cells
Eukaryotic Cells

25. Eukaryotic Cells Membrane-bound organelles Have nucleus
Most come from multicellular (plants/animals)
Can be unicellular (some protists – ameba & paramecium)
Larger

26. Prokaryotic No nucleus No membrane-bound organelles Contain Ribosomes
Single celled organisms (usually)
Smaller (usually)
Round DNA/RNA called Plasmids
Example: bacteria

27. Plant cell vs. Animal cell

28. What differences do you see?
Animal cell
Plant cell

29. Plants vs. Animal Plants contain: Cell wall Chloroplast Large vacuoles
Some animal cells contain vacuoles – smaller & more numerous
Why do plants need LARGE vacuoles?

30. Plants vs. Animal Animal cells contain: NO cell wall (only membrane)
Small vacuoles
Why would an animal only need SMALL vacuoles?

31. Organelle
Animal Cell
Plant Cell
Shape:
Round (irregular shape)
Rectangular (fixed shape)
Golgi apparatus:
Present
Cilia:
It is very Rare
Nucleus:
Mitochondria:
Cytoplasm:
Chloroplast:
Animal cells don't have chloroplasts
Plant cells have chloroplasts because they make their own food
Cell wall:
None
Yes
Plasma Membrane:
only cell membrane
cell wall and a cell membrane

32. Organelle
Animal Cell
Plant Cell
Flagella:
May be found in some cells
Lysosomes:
Lysosomes occur in cytoplasm.
Lysosomes usually not evident.
Ribosomes:
Present
Endoplasmic Reticulum (Smooth and Rough):
Vacuole:
One or more small vacuoles (much smaller than plant cells).
One, large central vacuole taking up 90% of cell volume.
Centrioles:
Present in all animal cells
Only present in lower plant forms.