1. Theory, Structure, Function
Cells
Theory, Structure, Function

2. What is a Cell?
The smallest unit that can carry on all the processes of life

3. Robert Hooke
1665 Cork Cells
“A lot of little boxes”
Dead Cells

4. Students write observations (20 sec), describe what they are looking at, any organelles?4

5. Students write observations (20 sec), describe what they are looking at, any organelles?5

6. Students write observations (20 sec), describe what they are looking at, any organelles?6

7. Cell Theory 1. All living things are made of one or more cells.
2. The basic unit of structure and function within an organism is the cell.
3. All cells arise from existing cells.

8. Cell Characteristics All cells have the following :
Plasma membrane – protective/selective barrier
Cytosol – semifluid to suspend components
Ribosomes
DNA – genetic material

9. Types of Cells Organisms are composed of one of two types of cells:
1. Prokaryotic – cell that lack a nucleus and other membrane-bound organelles
2. Eukaryotic – cell that has a true nucleus and membrane-bound organelles

10. What is a Prokaryotic Cell?
A cell that lacks a nucleus
Lacks other membrane bound organelles also
Typically small
An organism made of this type of cell is called a prokaryote
Ex - Bacteria

11. Unknown Bacteria of Death (400x)

12. Prokaryote History First cells to evolve (2.5 billion years ago)
Existing in a variety of environments (an extremely wide variety)

13. Types (Domains) of Prokaryotes
Archae – found in extreme environments
Bacteria – common bacteria (everyday bacteria)
** - Eukarya and Archae are more closely related to each other than either is to Bacteria (based on rRNA sequences)

14. Archae
Extreme environments! – salt beds, hydrothermal vents, swamps, sewage, cow guts

15. Bacteria Common everyday germs  Three shapes: Bacilli – rod
Cocci – sphere
Spirilla - helical

16. Prokaryotic Structure

17. What is a Eukaryotic Cell?
A cell that has a well defined nucleus
Contains membrane-bound organelles
Eukaryotic cells can specialize because they have organelles
Typically larger cells
Organisms composed of one/more eukaryotic cells is called a eukaryote
Ex. Plants, Fungi, Animals, Humans

18. Corn Stem (400x)

19. Eukaryotic Cells Can Specialize
Structure of a cell determines its function

20. Create a T-Chart
With your shoulder partner create a T- chart that state the Differences between Prokaryotes and Eukaryotes.
Prokaryotes Eukaryotes

21. Types of Eukaryotes Plant Cells: Animal Cells: Fungal Cells:
Cell Wall (Cellulose)
One Large vacuole (animals many small vacuoles)
Chloroplasts
Animal Cells:
Lysosomes
Centrosome (Organizes cytoskeleton/etc.)
Fungal Cells:
Cell Wall (Chitin)
Algae Cells (A type of Protist):

22. Numbers of Cells in Organisms
Unicellular – a complete living organism that consists of only one cell (prokaryote or eukaryote)
Examples – bacteria
Multicellular – a living organism consisting of more then one cell (only eukaryotes)
Examples – animals, plants

23. What is an organelle?
A cell component that performs specific functions
Example – nucleus, cell membrane

24. Cell Wall Only in plant/bacteria/fungi cells
Relatively inflexible (it’s rigid)
Protects and supports the cell
Castle Wall
Discuss gram +/- bacteria, the stain and how it affects pathogens (peptidoglycan in bacteria, cellulose in plants) 24

25. Cell Membrane “Filters” molecules
semi-permeable
Gives shape and flexibility to the cell
Bouncer
Do plasma membrane wksht 25

27. Nucleus The cell control center Contains chromosomes (DNA)
Involved in protein synthesis
Nucleolus makes ribosomes
Boss/Manager

28. Nuclear Membrane
Double membrane surrounding nucleus (protects and filters)
Has nuclear pores

29. Ribosomes The site of protein synthesis
Can be attached to the ER or float in the cytosol
Line workers/ Factory

30. Endoplasmic Reticulum
System of membrane tubes and sacs
Transport system of the cell
Modifies proteins for golgi (prepares them)
Also makes lipids/carbs
Rough = w/ribosomes
Smooth = no ribosomes
Roads

31. Golgi Apparatus
Processes, packages, and secretes cell products (such as proteins)
Uses vesicles for transport
Post Office

32. Vesicle Membrane-enclosed sac that transports and stores substances
Envelope (the package itself)

33. Mitochondria Breaks down food molecules and releases energy in
the form of ATP
Has DNA/ribosomes
Battery/Generator

34. Plastids Ex. Chloroplast Absorb light to create sugar
Photosynthesis
Give plants color (green pigment)
Have DNA/ribosomes
Solar Panel

35. Cytoplasm Space inside of the cell Nutrient rich
Semi-fluid material inside a cell - cytosol
Nutrient rich

36. Lysosome Contains digestive enzymes
Breaks down and rids the cell of waste
Prevents bacteria and viruses from invading
Janitor/Custodian

37. Vacuole Sack of fluid (water in plants) surrounded by a membrane
Stores food, enzymes or waste.
Storage closet

38. Cytoskeleton Maintains cell shape and size
Participates in movement (of cell itself and of material inside of the cell)
Scaffolding of building

39. Movement Organelles Cilia and Flagella
Hair-like organelles that extend beyond the surface of the cell
Assist in movement
Mobile business

40. Closing Quiz Cells
Which organelles propels a cell through an environment?
Which organelles are involved in the processing of a protein?
Which three organelles are present in plant cells but not animal cells?
What is the difference between a prokaryote and a eukaryote?
Mitochondria and chloroplasts have their own DNA, what does this imply about them?