1. Cytology
The study of cells

2. Cell Theory All living things are composed of cells
Cells are basic units of life
Earth billion years ago---life 3.5 billion years ago
Life: 1996 meteorite w/amino acids landed near mexico---could have started life
supernatural (no scientific explanation),
organic chemical evolution
New cells come from pre-existing cells

3. There’s always exceptions to the rule:
BUT….
How did the very first cell get here????
Viruses lack typical cell structure, use host
cells to reproduce
Mitochondria and chloroplasts have their own
genetic material/can reproduce independent
of cell

4. Then what do they have? Prokaryotic Cells Small Simple No Nucleus
No membrane bound organelles
Then what do they have?
Cell membrane
Cytoplasm
Monera
Same family as bacteria responsible for cholera
Plaque
Bacteria, algae
DNA:
Circular, not in nucleus
Ribosomes
Bacteria

5. Prokaryotic Structure
cytoplasm
with ribosomes
DNA
cell membrane

6. Organelle: Eukaryotic Cells More complex Larger
Plant cells
DNA in nucleus in long strands
Contain membrane bound organelles
Specialized compartment with a
specific function
Organelle:
DNA coiled
Plant (euglena), animal (cheek cell), fungi (yeast), protist
Animal cells
Fungi (Yeast)

8. Pro---No
Eu---Do
REMEMBER YOU ARE EUKARYOTIC!

9. Organelles
HW: give cell diagrams, label ---only checking in class

10. Oh where, oh where do we find cell organelles?
Cytoplasm (protoplasm):
The fluid inside a cell, but outside the nucleus
“Holds” organelles in place
Site of cellular chemical reactions
Link work at school?
Define organelles: “specialized organ”
Elodea, chloroplasts moving---transport material within cell, inc. rate of diffusion
Cyclosis:
Streaming movement of cytoplasm

11. Cytoplasm
Cytoplasm

12. Nucleus: Controls cell processes Contains hereditary information (DNA)
Nucleolus:
Ribosome formation
Chromatin (uncoiled DNA)

13. Nucleus
Nucleolus
Nucleolus
Nucleus

14. Mitochondria Release energy from food to make useable energy (ATP)
Outer and inner membranes
Inner membrane folded
(Increased surface area)
Found in:
Animal cells
Cellular respiration……..divide process similar to binary fission….asexual?!?!?!
Art gallery example---surface area---paper/cardboard box
Which cells likely to have lots of mitochondria?
Plant cells
Contain their own DNA!

15. Mitochondria
Mitochondria

16. Chloroplasts Site of photosynthesis
Convert light energy to chemical bond energy
Only in plant cells
Exceptions to plants: euglena-- Protist kingdom, blue green algae –monera NOT fungi (have cell walls)
Endosymbiotic theory: mitochondria/chloroplasts descendents of anaerobic prokaryotes---formed relationship w/aerobic eurkaryotes (+,+) Over time, nucleus took over more and more of the DNA from mito/chloroplasts
Contain their own DNA!

17. Chloroplasts
Animal cells don’t
have
chloroplasts!!!

18. Ribosomes Site of protein synthesis
Can be free in cytoplasm or attached to
endoplasmic reticulum

19. Ribosomes
Ribosomes

20. Endoplasmic reticulum
“ER”
A system of membranous sacs
Assembles components of cell membrane
Protein modification
Protein folding
Defect here may be involved in alzheimers, diabetes, ALS

21. Rough endoplasmic reticulum
Protein synthesis
Rough:
Ribosomes
RER
Smooth endoplasmic reticulum
Protein synthesis and transport----cell’s highway
Contains enzymes needed for cell
Ex. enzymes for lipid synthesis
Smooth:
No ribosomes
SER

22. Review parts of nucleus…show attached, transport mat’ls from nucleus

23. Rough ER
Smooth ER
Smooth ER
Rough ER

24. Golgi Who? apparatus, complex, bodies
Marks proteins for use in cell or
export (adds address w/proteins)
Produces digestive enzymes
Protein sorting, post translational modification
Autolysis (break down of old cell parts)

25. Golgi
body
Golgi body

26. Some proteins packaged for internal use

27. assorted
vesicles
Golgi
body
smooth ER
rough ER
DNA instructions for
building protein
chains leave the nucleus
and enter the cytoplasm.
Chains are
assembled on
ribosomes in cytoplasm.

28. Lysosome Packaged by Golgi body
Membranous sac filled with digestive enzymes
“Suicide Sacs”

29. Lysosomes

30. Lysosome
Lysosome

31. Vacuole Cell storage: Water Food Wastes Plants:
Water—pressure in vacuoles from liquid allows them to support heavy structures
Food, water----maintain homeostasis
Plants:
One large central vacuole
Animals:
Few small vacuoles
Vacuoles are crucial in single-celled organisms to
maintain homeostasis

32. Vacuole

33. Cell Wall Provides support Provides shape Made up mostly of cellulose
Animal cells don’t have!
Fungi kingdom—cell wall, some monera (algea)
Masons/cement blocks arranged same as cell walls
Indigestible----egestion

34. Cell wall
Animal cells
don’t have
cell walls!!!

35. Centriole Used in cell division Animal cells only
Microtubules used in cell division, right outside nuclear membrane
Talk about later

36. Plant cells
don’t have
centrioles!!!
Centriole

37. Cilia: Flagella: Locomotion Moving substances across surface of cell
Humans: cilia in lungs to rid dirt, cilia in ovaries to sweep out egg

38. Cilia

39. Plasma membrane/cell membrane
Plant AND animal cells
Controls what goes in and out of cell
Protection
Support

40. Cell
membrane
Cell
membrane

41. Lipid Bilayer Main component of cell membranes lipid bilayer fluid

42. Cell (Plasma) Membrane Structure
☼ 2 layers of phospholipids
(lipids with phosphate groups attached)
☼ Proteins - embedded in lipid layers- for
transport or receptors
☼ Carbohydrates - attached to surface proteins
or lipids – markers
☼ Lipids & Proteins can move along membrane
= “Fluid”
FLUID MOSAIC MODEL of Cell Membrane

44. Receptors recognize substances (hormones etc.)
Turn something on inside cell…like light switch
Receptors recognize substances (hormones etc.)
and allow them to enter cell

46. How are plant and animal cells different?
Plant Cells
Cell Walls
Chloroplasts
Centrioles
Golgi Bodies
Vacuoles NO
YES NO
YES
YES NO
1 or 2
100 +
Many Small
Few Large

47. Cell wall
Chloroplasts
Cell
membrane
Vacuole
Mitochondria
Lysosome
Ribosomes
Golgi
body
Nucleus
Rough endoplasmic
reticulum
Nucleolus
Smooth
endoplasmic
reticulum
Cytoplasm

48. Cilia
Golgi body
Cell membrane
Centrioles
Smooth endoplasmic
reticulum
Lysosomes
Free ribosomes
Mitochondria
Nucleolus
Rough endoplasmic
reticulum
Nucleus
Cytoplasm

49. Staining Techniques Applying stain makes cell structures more visible
Can be useful in identifying organisms
Example:
Methylene blue
Iodine starch indicator (blue black in presence of starch)

50. Which plant, which animal (green chloroplast) importance of stains
Note the large nucleus and nucleolus in the center of the cell, mitochondria (red) and plastids in the cytoplasm

51. Organization
of Life
Organelle
Cell
Tissue
Organ
Organ System
Organism