1. What is the Cell Theory? Cell Theory:
All living things are composed of cells
Cells are basic unit of structure and function in living things
All cells come from preexisting cells

2. What are the 2 major classes of cells?

3. What are the 2 major classes of cells?
Prokaryotic:
Lack nucleus/most other organelles
Occur earliest in history of life
Examples?
Bacteria
Eukaryotic:
Has nucleus/other organelles
Animal/plant/fungi/protists

4. What are the 2 major classes of cells?

5. What are the similiarities between animal/plant cells?

6. What are the similiarities between animal/plant cells?
Organelle:
Each part of cell that has a specific function
Plasma membrane:
Thin outer covering
Defines boundary of cell and regulates traffic of chemicals between the cell and its surroundings
Nucleus:
Holds genetic information
Cytoplasm:
Region between nucleus and plasma membrane (fluid like)

7. What are the similiarities between animal/plant cells?
Mitochondria
Supplies cell energy (ATP)
Endoplasmic Reticulum
Protein translation/protein transport
Golgi Apparatus
Processes and package macromolecules
Vacuoles
storage

8. What are the similiarities between animal/plant cells?

9. What are the differences between animal/plant cells?
Chloroplasts:
Organelle that is the site of photosynthesis
Cell Wall:
Protects cell and holds shape

10. What molecules make up a cell membrane?
What is unique about the interaction of lipids and water?
Why do lipids work well for a cell’s boundary, given the fluid inside and surrounding cells?

11. What is the function of a cell membrane?
Keeps the cell organized
Regulates flow of material

12. What is membrane structure?
Made up mostly of proteins and lipids
Phospholipid:
2 fatty acid TAILS
1 Head

13. Biological Membranes are Bilayers
two layers of lipids
each layer has hydrophillic portion
hydrophobic portion inside associated with other fatty acids

14. Hydrophillic Region
Hydrophobic Region

15. Biological Membranes have a lot of lateral mobility
“fluid mosaic”

17. Functions of Membrane Proteins
Connection to other cells
Transport molecules across membrane
Membrane associated enzyme activity

19. How do molecules cross a membrane?
Passive Transport
Movement of molecules across a membrane without input of energy
Molecules move from high concentration to low concentration
Active Transport
Movement of molecules across a membrane with input of energy
Molecules move from low concentration to high concentration

20. What is passive transport?
Some membranes are selectively permeable
some molecules can cross easily, some molecules cannot
Passive Transport:
Diffusion across a membrane
No energy is required
Oxygen/carbon dioxide

21. Molecules always diffuse from areas of high concentration to low
There is energy in concentration gradients

22. What are examples of passive transport?
Diffusion:
The net movement of particles from an area of high concentration to low concentration
Produces equilibrium

24. What is Osmosis? Osmosis:
Passive transport of water from high concentration to low concentration
Hypertonic
when solution has higher concentration of solute than the cell
Hypotonic
When the solution has a lower concentration of solute than the cell
Isotonic
When the solution has equal concentration of solute than the cell (equilibrium)
Where will water move into the cell or out of cell?

28. Water diffuses from areas of high concentration to low
little external solutes
lots of external solutes

29. Membranes are semi-permeable
Some molecules can cross membrane, many can’t
More hydrophobic molecules can cross membrane more easily

30. What is facilitated diffusion?
Transport proteins embedded in membrane provide a pathway for certain molecules to pass
Water, sugars

32. Proteins act as portals
Many molecules can’t get across on their own
Protein channels allow specific molecules to cross

33. What is Active Transport?
Requires energy to transport molecules across a membrane
A transport protein pumps molecules across membrane, usually against concentration gradient
Opposite way than diffusion
THE TRANSPORT PROTEIN RECOGNIZES CERTAIN MOLECULES (SOLUTES). WHAT OTHER PROTEIN HAS THIS TYPE OF RECOGNITION?
Enzymes!!!!

34. Use ATP to move molecules against their concentration gradient
Active Transport
ATP
ADP
Use ATP to move molecules against their concentration gradient

36. How do large molecules cross membranes?
Vesicles:
Small membrane sacs
Hold large molecules to open up into cell or out of cell

37. How do large molecules cross membranes?
Exocytosis:
Vesicle expels contents out of cell
Endocytosis:
Vesicle takes material into cell by budding into cell

39. Endocytosis