1. With your host…Ms. Turner!
O-Chem, Lipids, Cell Membrane & Transport
Test Review
With your host…Ms. Turner!

2. 10 20 30 40 50 Organic Chemistry Lipids Cell Membrane
Membrane Transport
Miscellaneous 10 20 30 40 50

3. What 4 atoms make up 96% of living organisms?
Organic Chemistry : 10
What 4 atoms make up 96% of living organisms?
ANSWER

4. Organic Chemistry : 10 - Answer
Carbon Hydrogen Oxygen Nitrogen

5. Organic compounds have BOTH
Organic Chemistry : 20
Organic compounds have BOTH
_____ and _____.
ANSWER

6. Organic Chemistry : 20 - Answer
Organic compounds have BOTH Carbon and Hydrogen.

7. How many bonds can carbon make?
Organic Chemistry : 30
Carbon-based molecules come in three fundamental structures. What are the 3?
How many bonds can carbon make?
(which contribute to its ability to make these various structures…)
ANSWER

8. Organic Chemistry : 30 - Answer
Carbon forms 4 bonds (because it has 4 valence electrons and would need 4 more to have a full outer energy shell).

9. *Don’t forget to mention the role of water.
Organic Chemistry : 40
What is the difference between dehydration synthesis and hydrolysis?
*Don’t forget to mention the role of water.
ANSWER

10. Organic Chemistry : 40 - Answer
Dehydration synthesis is the process in which smaller molecules are joined together to make larger molecules by taking out a water molecule. Hydrolysis is breaking down larger molecules into its smaller parts by adding water to split it up.

11. Draw a diagram of dehydration synthesis.
Organic Chemistry : 50
Draw a diagram of dehydration synthesis.
ANSWER

12. Organic Chemistry : 50 - Answer
+ H2O
+ H2O

13. What three atoms make up lipids?
ANSWER

14. Carbon, Hydrogen, and a little bit of Oxygen.
Lipids : 10 - Answer
Carbon, Hydrogen, and a little bit of Oxygen.

15. What does it mean for lipids to be insoluble in water?
(aka not soluble in water)
What property accounts for this? (aka we could say the lipids are ___-_____)
ANSWER

16. Lipids : 20 - Answer
It means the lipids do not dissolve in water. Lipids are non-polar (Which means they don’t have a charge like polar molecules do. Their charges balance out.) Like dissolves like. Polar substances are soluble in other polar substances.

17. Name 3 functions of lipids.
(Could be the function of any of the types of lipids we covered)
ANSWER

18. Lipids : 30 - Answer
Store large amounts of chemical energy (fats & oils i.e. triglycerides)
Forms a selective barrier in cell membranes (phospholipids)
Maintains flexibility and strength of cell membranes (steroids – cholesterol)
Signaling molecules (steroids – hormones)

19. Lipids : 40
Draw an example of a saturated fatty acid and an unsaturated fatty acid.
(*Don’t forget the carboxyl group. You will not have to draw these on the test…but you may have to identify the difference between saturated and unsaturated)
ANSWER

20. Lipids : 40 - Answer
Saturated Unsaturated

21. Double
Jeopardy!!

22. Include in your answer a description of the lipid bilayer.
Lipids : 50
Explain why the phospholipid is a suitable molecule for creating a selective barrier for a cell.
Include in your answer a description of the lipid bilayer.
ANSWER

23. Lipids : 50 - Answer
The phospholipid has two main parts – the hydrophilic head which includes the polar phosphate group and the hydrophobic fatty acid tails that are nonpolar. The nonpolar tails face each other to make two layers of the phospholipids with the polar heads facing the watery environments of inside and outside the cell. The tails face each other and prevent certain substances from going through based on polarity (charge) and size.

24. What are the two main jobs of the cell membrane?
ANSWER

25. Cell Membrane : 10 - Answer
To provide a barrier between the inside and the outside of the cell. To regulate what moves in and out of the cell. *both of which help to maintain homeostasis

26. Cell Membrane : 20
Draw a sketch of a lipid bilayer and identify the area that is hydrophobic and the area that is hydrophilic.
ANSWER

27. Cell Membrane : 20 - Answer
Hydrophilic Heads
Hydrophobic Tails

28. Name the three types of membrane proteins.
Cell Membrane : 30
Name the three types of membrane proteins.
ANSWER

29. Cell Membrane : 30 - Answer
Receptor Proteins Marker Proteins Channel Proteins

30. Cell Membrane : 40
Name two types of proteins that can be found in the cell membrane and explain their function.
ANSWER

31. Cell Membrane : 40 - Answer
Receptor proteins: transmits information from outside the cell to the inside (e.g. hormones like insulin trigger glucose intake). Marker proteins: allows the body/cell to recognize self from non-self (e.g. to aid the immune system in identifying harmful bacteria). Channel proteins: allows the passage of molecule through the cell membrane (e.g. molecules that are too big or polar can’t go through the lipid bilayer unaided).

32. Cell Membrane : 50
What is the name of the model used to describe the cell membrane?
Explain why these two words are used to describe the cell membrane.
ANSWER

33. Cell Membrane : 50 - Answer
Fluid Mosaic Model Fluid – the phospholipids within the lipid bilayer can move around each other laterally (very rarely would they switch sides in the bilayer) making the membrane flexible and more fluid. Mosaic – although the main component of the cell membrane is phospholipids, it also has proteins that are spread out in the membrane which resembles a mosaic.

34. What is the difference between passive transport and active transport?
Membrane Transport : 10
What is the difference between passive transport and active transport?
ANSWER

35. Membrane Transport : 10 - Answer
Passive transport does not require energy (in the form of ATP) while active transport does.
Passive transport involves movement of molecules from high concentration to low concentration and active transport is the opposite (low to high).

36. Membrane Transport : 20
Define osmosis.
ANSWER

37. Membrane Transport : 20 - Answer
Osmosis is a type of passive transport. It is the movement of water across a membrane from an area of higher concentration of water to low concentration until equilibrium is reached.

38. A pump is a special type of channel protein.
Membrane Transport : 30
A pump is a special type of channel protein.
What does it do?
ANSWER

39. Membrane Transport : 30 - Answer
A pump is used for active transport and moves molecules against the concentration gradient from an area of low concentration to high concentration.

40. How is exocytosis different from endocytosis?
Membrane Transport : 40
How is exocytosis different from endocytosis?
What are the two types of endocytosis?
ANSWER

41. Membrane Transport : 40 - Answer
Exocytosis is bringing large or large amounts of molecules out of the cell using vesicles which endocytosis brings them in. Two types of endocytosis: (1) Phagocytosis, (2) Pinocytosis

42. Membrane Transport : 50 ANSWER1. 2. 3. 4. 5. 6.
Name the possible consequences of osmosis for animal and plant cells.
ANSWER

43. Membrane Transport : 50 - Answer
Crenation
Normal
Cytolysis
Plasmolyzed
Flaccid
Turgid
**Normal**

44. What does it mean to say that the cell membrane is semi-permeable?
Miscellaneous : 10
What does it mean to say that the cell membrane is semi-permeable?
(AKA selectively permeable)
ANSWER

45. Miscellaneous : 10 - Answer
Semi-permeable means that some molecules can pass through the membrane while others cannot.

46. Miscellaneous : 20
Draw a picture that represents a cell membrane that has a concentration gradient.
Draw an arrow that shows going “with” or “down” a concentration gradient.
ANSWER

47. Miscellaneous : 20 - Answer

48. What is the role of cholesterol within the cell membrane?
Miscellaneous : 30
What is the role of cholesterol within the cell membrane?
ANSWER

49. Miscellaneous : 30 - Answer
Cholesterol maintains the flexibility of the cell membrane (it helps to provide space between phospholipids so they can remain more fluid). It also helps to maintain the strength of the membrane and not allow the phospholipids to pull apart too far.

50. Miscellaneous : 40
If a plant cell with a 2% solute concentration is placed in a solution with a 4% solute concentration explain what could happen and WHY – using proper vocabulary.
ANSWER

51. Miscellaneous : 40 - Answer
If the cell has a 2% solute concentration (compared to 4% in the solution making the solution hypertonic) then it has 98% water. The solution it is placed in has a 96% water concentration so water will move out of the cell (the water moves from a higher concentration to a lower concentration). The cell would shrivel up resulting in plasmolysis.

52. What type of transport is facilitated diffusion?
Miscellaneous : 50
What type of transport is facilitated diffusion?
How does it work?
ANSWER

53. Miscellaneous : 50 - Answer
Facilitated diffusion is a type of passive transport. It is when molecules move from a high concentration to a low concentration but cannot move through the lipid bilayer due to size or charge/polarity or shape thus a channel protein is used to get the molecules through.