1. Cytology - the study of cells
Mrs. Silverberg
Biology

2. Anton van Leeuwenhoek
1670 – Dutch cloth merchant
First scientist to observe living cells
Father of microscopy

3. Anton van Leeuwenhoek Saw life in pond water First to observe Sperm
Red blood cells
Gunk from teeth

4. Leeuwenhoek's microscope consisted simply of:
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

5. Robert Hooke
1665 – English
Named cells after the small boxy rooms that monks live in

6. Robert Hooke
He first saw and named "cells" while he was experimenting with a new instrument we now call a "microscope."
For his experiment he cut very thin slices from cork. He looked at these slices under a microscope.
He saw tiny box-like shapes.

7. Matthias Schleiden 1830 – German Botanist All plants are made of cells
"One who wishes to be a botanist or zoologist without a microscope, is at least as great a fool as one who wants to observe the heavens without a telescope”

8. Theodor Schwann 1830 - German Worked with Schleiden
Discovered all animals are made of cells

9. Rudolf Virchow CELL THEORY: * All cells come from pre-existing cells
* Cell Division
* First Cell?

10. The Cell Theory 1. All organisms are composed of one or more cells
2. The cell is the basic unit of organisms
3. All cells come from preexisting cells

11. Cytology – the study of cells
Three basic parts of a cell
1 cytoplasm
2 nucleus
3 cell membrane

12. Two Kinds of Cells Prokaryotic Cells
Small
Simple
No nucleus
Bacteria

13. Eukaryotic cells - all other cells
These include
protists
fungi
plants
animals
Have a nucleus
Cells contain structures called organelles.

14. Prokaryotic vs. Eukaryotic

15. Plasma membrane
All cells are surrounded by a plasma membrane. It separates the contents of the cell from its environment and regulates the passage of molecules into and out of the cell. 

16. Active cells
An actively metabolizing cell needs a large surface area. Cells are limited in size because larger cells have a smaller surface to volume ratio.

17. Surface:volume
Notice that the larger cube has more surface area and more volume but less surface area for each cubic centimeter of volume.   For any given geometric object (cubes, spheres, etc.), smaller objects have a greater surface to volume ratio (surface:volume) than larger objects of the same shape.

18. Surface: Volume
Compare the surface to volume ratio (surface: volume) of a cube that is 1 cm X 1 cm X 1 cm with that of a cube that is 10 cm X 10 cm X 10 cm.

19. Larger cube (10 cm X 10 cm X 10 cm)
The surface area of one side = 10 cm X 10 cm = 100 square cm (or 100 cm2).
There are 6 sides, so the total surface area = 600 X  cm2 = 600 cm2.
Volume = 10 cm X 10 cm X 10 cm = 1000 cubic cm (or 1000 cm3)
Surface:Volume = 600 cm2/1000 cm3 = 0.6 cm2/cm3 (or 0.6 square cm of surface area for each cubic cm of volume).

20. Smaller cube (1 cm X 1 cm X 1 cm)
The surface area of one side = 1 cm X 1 cm = 1 square cm (or 1 cm2).
There are 6 sides, so the total surface area = 6 X  cm2 = 6 cm2.
Volume = 1 cm X 1 cm X 1 cm = 1 cubic cm (or 1 cm3)
Surface:Volume = 6 cm2/1 cm3 = 6 cm2/cm3 (or 6 square cm of surface area for each cubic cm of volume)

21. Cell volume : surface area
Every cell is surrounded by a plasma membrane. Most cells are very small and therefore have a high ratio of plasma membrane surface to cell volume. 

22. Parts of a Eukaryotic Cell

26. Cell Membrane Flexible Like skin surrounding the cell
Selectively permeable: controls movement of materials into and out of the cell

27. Lipids & Proteins
Lipid bilayer: hydrophilic heads point outwards; hydrophobic tails point inward
Proteins move materials (lipids) into and out of the cell:
peripheral proteins: attach to the internal & external surface
integral proteins: found within lipid bilayer

28. Cytoplasm
Cytoplasm: material found between cell membrane and nucleus
Cytosol: gelatin-like fluid organelles are bathed in

29. Mitochondria The power plant
provides energy to the cell
Chemical reactions transfer energy from organic compounds to ATP
Cristae: internal, long folds; increase surface area so more reactions can occur

30. Ribosomes
Site of protein synthesis

31. Rough Endoplasmic Reticulum (RER)
Network of tubes and sacs that serve as a highway for molecules to move along
Lots of ribosomes on it

32. Smooth Endoplasmic Reticulum (SER)
Tubes and sacs that work as the cell’s highway
Not covered with proteins

33. Golgi Apparatus AKA Golgi Complex
Process, package, and secrete proteins
Series of flattened sacs

34. Lysosomes
Small sacs
Enzymes digest organic molecules and old organelles
“Clean up”
Common in animal cells, rare in plant cells

35. Cytoskeleton
A network of long protein strands in the cytosol that help maintain cells shape and size
Microfilaments: made of protein called actin; these are the smaller strands that contribute to cell movement and contraction of muscles
Microtubules: larger, hollow tubules; include spindle fibers that assist in cell division

36. Cilia
Small beating hairs
Means of movement
Many

37. Flagella
Whip like structure
Means of movement
Few

38. Nucleus Largest organelle Contains the cell’s DNA
Manages the cells functions
“the brain” of the cell

39. Nuclear membrane or envelope
Membrane that surrounds the nucleus
Controls movement of materials into and out of the nucleus

40. Nucleolus
Part of the nucleus
Site where ribosomes are synthesized

41. Plant Cells
Cell Wall
Vacuoles
Plastids: Chloroplast

42. Cell wall Rigid wall around cell to provide support Made of cellulose
Only in plant cells

43. Vacuole Large storage sacs Larger in plants than animals
Store wastes and in plants store glucose from photosynthesis

44. Chloroplasts Only in plant cells
Transforms sunlight into usable energy for the cell
Chlorophyll is the green pigment that traps the sunlight