2. CELL Parts and CELL Membrane REVIEW

3. Name the cell part that corresponds to the function

4. Control Center (Brain of the Cell) The Nucleus

5. Makes Ribosomes and is found inside the Nucleus The Nucleolus

6. Where proteins are made? On the Ribosomes

7. Packages, stores, and distributes proteins; pancake-shaped layers Golgi Apparatus

8. Thick fluid inside cells CYTOPLASM

9. Hair-like extensions that help cells sense their surroundings Cilia

10. Has a double membrane called the “nuclear envelope” The Nucleus

11. Folded membrane that transports proteins throughout the cell The Endoplasmic Reticulum

12. Contains chlorophyll, found only in plant cells Chloroplast

13. The “powerhouse” of the cell, site where ATP is made Mitochondria

14. Boundary of the cell, found in both plant and animal cells The cell membrane

15. Digests (breaks down) wastes and old cell parts, kills bacteria and viruses Lysosome

16. Tail-like extension that helps move some cells through watery environments Flagella

17. Stores water, wastes, and nutrients for plants Central Vacuole

18. Rigid outside boundary for plant cells Cell Wall

19. Now let’s examine the Membrane! What does selective permeability mean? Selective= choosy, picky, doesn’t let just anything in. Permeable= allow substances to enter and exit. Selective permeability= the ability of the membrane to let some things in and keep others out.

20. The membrane is made of these! Phospholipid Molecules They have the following parts: Phosphate and Glycerol Head (polar) Fatty Acid Tails (nonpolar)

21. Why is the membrane so fluid? Fatty acid tails are unsaturated (kinked) so they don’t compress Cholesterol is embedded (stuck in) between the tails

22. What other components make the membrane a mozaic? transport proteins What are three examples of transport proteins? 1. gated proteins 2. channel proteins 3. receptor proteins

23. Why are transport proteins needed? They allow substances that are too… Big, charged or polar to cross the membrane.

24. What substances can or cannot pass easily across the membrane? CANCANNOT  Polarity NonpolarPolar  Size SmallLarge  Charge UnchargedCharged

25. What is a concentration gradient? Different concentrations of molecules between two areas. If there is no difference, there is no gradient— You have equilibrium!

26. When is there equilibrium? When there is an equal concentration of molecules on both sides of a membrane or throughout the space. Why is it called “Dynamic” Equilibrium? The molecules are always moving (dynamic), but the concentration stays equal.

27. Movement of molecules from high concentration to low concentration Diffusion

28. Diffusion of Water Molecules Osmosis

29. Two types of Transport: Active Transport Passive Transport

30. Name kinds of Passive Transport- Remember-- no additional energy required Diffusion Osmosis Facilitated Diffusion=movement down a gradient for substances that cannot easily cross the membrane– they need to be helped or assisted by a ……. Transport protein

31. Name two kinds of Active Transport– these require energy input Endocytosis– Endo= IN Exocytosis- Exo = Exit

32. Solutions: Hypertonic Hypotonic Isotonic Which has more dissolved solutes? Hyper Which has more H2O? Hypo

33. Water always moves from …… Hypo to Hyper Hypotonic solutions-- (mo H2O) To Hypertonic solutions-- more solutes, but less H2O

34. Thank you and Good-Luck!

35. Plant cells need water to maintain upright structure. What is this pressure called? Turgor Pressure When a plant loses turgor pressure, it loses water from osmosis. That’s called…… Plasmolysis