1. DNA 3/13/17
Refresher: What are the 6 criteria for life?

2. Abiotic Ecology Reassessments this Thursday, 3/16 in OH
Must show me your notes for all sections of abiotic ecology, as well as your original quiz. (HAVE THESE ORGANIZED AND READY AT 8AM)
I will ask you 1 question for each section that you need to reassess.
All cycles are fair game!

3. For funzies…
Fold your thumb in to the palm of your hand. Then, try the following activities without using your thumb: 1. writing your name. 2. untying your shoe 3. picking up your notebook. How does the structure of your hand (thumb included) help you perform these functions?

4. Nature is smart!
In living things, structure (what something looks like) and function (what something does) tend to be aligned. In today’s lesson, we will see how the structure of cellular organelles help the cell perform the 6 functions required for life.

5. Reminder of hierarchy…
Atoms
Molecules
Macromolecules
Organelles
Cells
Eukaryotic Cells
Prokaryotic Cells
Animal Cells
Plant Cells
Viruses

6. There are two major cell types:
EUKARYOTIC and PROKARYOTIC
“true” “nut/kernel” “before” “nut/kernel”
Eukaryotic cells have membrane-bound organelles. Prokaryotic cells do not. Prokaryotic cells were here first.

7. Prokaryote vs Eukaryote
Prokaryotes
Do not have membrane- bound organelles and a nucleus
Ex: Bacteria
Eukaryotes
Have membrane-bound organelles and a nucleus
Ex: Fungi, Plants, Animals, You!

8. Other differences…

9. ALL CELLS (eukaryotic and prokaryotic) HAVE:
1) Cell membrane
2) Cytoplasm
3) DNA
4) Ribosomes

10. STRUCTURE AND FUNCTION Flash back to Friday…
What were some similarities and differences that you observed between human cheek cells and onion cells?

11. Structure: Why are plant cells rectangular, while cheek cells are round/globular?
The reason is linked to the cells’ function: What is the difference between an onion plant’s job and your mouth’s job?

12. Onion Cells
Structure: The rectangular, blocky looking structures that you see are the cells. The dark line surrounding each rectangle is an organelle called the cell wall.
Function: Cell walls offer structural support. They let each cell fill up with more water without bursting. This keeps the cells “full” and upright. Since plants have no skeleton, they use turgor pressure (pressure of water against the inside of the cell) to stand up. This is important because plants need to access light to survive. (limp plants have low turgor pressure. They are not “full.”)

13. Cheek Cells
Structure: The cells are round/globular. They do not have cell walls, so their shape is less rigid and structured.
Function: The human mouth is the first site of digestion. You would not want your mouth cells to be rigidly structured like a plant cell, because the inside of your mouth needs to be able to move and connect fluidly with the other cells in your body.

14. Are all plant cells rectangular and all animal cells globby glob shaped?

15. Are all plant cells rectangular and all animal cells globby glob shaped?
NO! The structure depends on the function.
NO!

16. We’ve seen that cell structure depends on function.
How do organelle structures contribute to organelle function, and the function of the cell as a whole?
In the body, there are organs. In the cell, there are organelles.

17. CASE STUDY PROJECT!

18. DNA 3/15 All cells have a nucleus Fungi are prokaryotes
TRUE OR FALSE:
All cells have a nucleus
Fungi are prokaryotes
Some animal cells have cell walls
Vacuoles store nutrients, waste, and water
The endoplasmic reticulum is an organelle that helps fold and synthesize proteins.

19. DNA 3/16/17 1) golgi apparatus 2) endoplasmic reticulum
Write an analogy about:
1) golgi apparatus
2) endoplasmic reticulum
3) cell membrane

20. DNA 3/22/17: Turn your case study paragraphs in to dropbox!
What are two differences between the rough ER and the smooth ER?

21. 25 min data collection/ writer’s workshop
 If you are already done collecting data:
Have me sign it off
Write 3 questions that you want feedback on/ ask for feedback
Start typing your data section (look at the rubric and examples on my DP!)

22. Clean Up/ Reading Example Data Sections
Groups that need to do dishes:
Read data sections of example labs on my DP. Write bullet points for what you notice about the section’s structure and function.

23. DNA 2/23/17
Which of the following DOES NOT belong in the data section of an APA lab report?
The rats chose to open the door that would save their companions more frequently than they chose to open the door to the candy bar.
The rats that had been saved from drowning the previous day swam an average of 3 hours longer than rats that had never been placed in the water tank. This is likely because they had learned that the drowning was a planned event with a scheduled end.
The rats in control of the lever demonstrated distressed behavior, such as high pitched squeaking and erratic movement.
Twelve percent of rats chose to eat the candy bar before rescuing their companion.
All of the above belong in the data section.

24. Example Data Sections
YES!  NO :/

25. Game Plan: Non-honors:
I will check your case study video script at the end of class. (you do not need the visual aid yet. We will make them tomorrow.)
Honors: We will have meetings today, and you will work on case study video scripts tomorrow.

28. DNA 3/27/17
What are some things that you bring into your home because you need them?
What are some things that are not wanted in your home so you keep them out?
What are some things that are sent out of your house?

29. The Gatekeeper of the Cell
Cell Membrane:
The Gatekeeper of the Cell
Review expectations for whiteboards.

30. Class Brainstorm
What properties could the cell membrane use to distinguish between molecules? Physical Properties Chemical Properties

31. What is the cell membrane?
Every cell is surrounded and protected by a plasma membrane (aka cell membrane)
The cell membrane is made mostly of lipids, carbohydrates, and some protein channels

32. What does the cell membrane do?
The cell membrane has two main jobs:
1. It separates the inside of the cell (the intracellular space) from the outside of the cell (the extracellular space)
2. It acts as a gatekeeper by only allowing certain molecules in or out

33. Components of the Cell Membrane
The cell membrane is made of special lipids called phospholipids
Phospholipids have two parts:
Hydrophilic (water-loving), or polar heads
Hydrophobic (water-fearing) or nonpolar tails

34. Drawing out phospholipids

35. Other parts of the cell membrane
Several types of proteins are embedded in the cell membrane.
Two major ones are:
Protein channels: proteins that allow a passage way into and out of the cell
Protein receptors: Binds to a signaling molecule outside of the cell that causes a reaction inside of the cell

36. Other parts of the cell membrane
The cell membrane also has carbohydrates on the outer surface that play a role in cell recognition and cholesterol around the lipid tails to regulate membrane fluidity

37. Modeling the Cell Membrane
Work together with your shoulder partner to make a model of the cell membrane
Make sure you READ each step carefully and WORK together!
Q-tip = Phospholipid
String = carbohydrate
Straw = Protein channel
Cholesterol
Cotton ball = nucleus
Candle = protein receptor

38. Step 1: Identifying the phospholipid
First identify which parts of the q-tip are the polar phosphate head and the nonpolar lipid tail
Which part does not want to come into contact with water?
Q-tip = Phospholipid

39. Step 2: Building the cell membrane
Imagine that the surface of your desk is made up of water. Arrange your q-tips in a way so that the minimum number of hydrophobic (nonpolar regions) are exposed to water.

40. Step 3: Building the cell membrane
Arrange your q-tips in a way that results in an inner compartment that can also have water.
Water inside

41. Step 4: Building the cell membrane
Add your protein receptor and channels to the membrane to allow things to communicate and enter/exit the cell.
Straw = Protein channel
Candle = protein receptor

42. Step 5: Adding cholesterol and carbohydrates
Snugly pack the cholesterol strands between the lipid tails.
These cholesterol molecules help maintain membrane fluidity
Add carbohydrates to the outer layer of phospholipids.
These carbohydrates allow the cells to be recognized by other cells and molecules (and viruses yikes!)
Cholesterol
String = carbohydrate

43. Step 6: Nucleus Add your nucleus to the cell.
Is this cell a eukaryotic or prokaryotic cell? How do you know?
What does the nucleus hold in these cells?
Cotton ball = nucleus

44. Drawing out our cell membrane

45. DNA 3/28/17
Match the analogy to a part of the cell membrane, and explain why:
A dog’s ID tag
A cell phone
A 2 year-old who doesn’t know how to swim
Michael Phelps
A boba straw

46. What does the cell membrane do?
The cell membrane helps cells maintain homeostasis by allowing SOME things to enter/exit the cell and not others – it is SEMI- PERMEABLE

47. Questions:
If ANYTHING could freely move in and out of the membrane, would it still be called semi-permeable?
If NOTHING could move in and out of the membrane, would it still be called semi-permeable?

48. Semi-permeable Semi = Partially
Permeable = Allowing things to pass through
Semi-permeable means that some things can enter and leave while other things cannot

49. IS IT SEMI-PERMEABLE? ASK YOURSELF:
Yay = Thumbs up
Nay = Thumbs down
ASK YOURSELF:
Are only certain things able to go in and out? If yes, it is SEMI-PERMEABLE

50. The White House

51. Saya’s class during lunch…

52. An Exclusive Club

53. Quick check
What are two types of proteins that are part of the cell membrane? What are their functions?
What is it called when the cell membrane chooses to let certain things through, but not all things?

54. Share with Your Partner
What are some things that you bring into your home because you need them?
What are some things that are not wanted in your home so you keep them out?
What are some things that are sent out of your house?

55. The Gatekeeper of the Cell
The Cell Membrane:
The Gatekeeper of the Cell
Review expectations for whiteboards.

56. What does Alice have to do with Cell Membranes?

57. Class Brainstorm
What properties could the cell membrane use to distinguish between molecules? Physical Properties Chemical Properties

58. What is the cell membrane?
Every cell is surrounded and protected by a plasma membrane (aka cell membrane)
The cell membrane is made mostly of lipids, carbohydrates, and some protein channels

59. What does the cell membrane do?
The cell membrane has two main jobs:
1. It separates the inside of the cell (the intracellular space) from the outside of the cell (the extracellular space)
2. It acts as a gatekeeper by only allowing certain molecules in or out

60. Components of the Cell Membrane
The cell membrane is made of special lipids called phospholipids
Phospholipids have two parts:
Hydrophilic (water-loving), or polar heads
Hydrophobic (water-fearing) or nonpolar tails

61. Drawing out phospholipids

62. DNA 1/28/16
Draw a phospholipid. Label the two parts of phospholipids that make up the phospholipid bilayer.
Which part of the phospholipid is hydrophobic? Which part is hydrophilic?

63. Announcements Tomorrow = last day of plant data collection
Case study paragraphs due tonight at 11:59 PM.
Plant data section due Tues at beginning of class. (hard copy in class for peer review. No turnitin submission)

64. Today! 1. Collect and record plant data.
There is a hiring symposium that I am sneaking away to watch. Here is what to do:
1. Collect and record plant data.
2. Work on case study paragraphs (peer revise all paragraphs in your group to make sure that the reasoning makes sense for all 4!! Use the rubric!)
3. Make revisions to intro and methods section of plant lab. (If I have not written your feedback yet, look at someone’s feedback within your group. There were a lot of common errors)

65. Other parts of the cell membrane
Several types of proteins are embedded in the cell membrane.
Two major ones are:
Protein channels: proteins that allow a passage way into and out of the cell
Protein receptors: Binds to a signaling molecule outside of the cell that causes a reaction inside of the cell

66. Other parts of the cell membrane
The cell membrane also has carbohydrates on the outer surface that play a role in cell recognition and cholesterol around the lipid tails to regulate membrane fluidity

67. Activity: Modeling the Cell Membrane
Work together with your shoulder partner to make a model of the cell membrane
Make sure you READ each step carefully and WORK together!
Q-tip = Phospholipid
String = carbohydrate
Straw = Protein channel
Cholesterol
Candle = protein receptor
Cotton ball = nucleus

68. Step 1: Identifying the phospholipid
First identify which parts of the q-tip are the polar phosphate head and the nonpolar lipid tail
Which part does not want to come into contact with water?
Q-tip = Phospholipid

69. Step 2: Building the cell membrane
Imagine that the surface of your desk is made up of water. Arrange your q-tips in a way so that the minimum number of hydrophobic (nonpolar regions) are exposed to water.

70. Step 3: Building the cell membrane
Arrange your q-tips in a way that results in an inner compartment that can also have water.
Water inside

71. Step 4: Building the cell membrane
Add your protein receptor and channels to the membrane to allow things to communicate and enter/exit the cell.
Candle = protein receptor
Straw = Protein channel

72. Step 5: Adding cholesterol and carbohydrates
Snugly pack the cholesterol strands between the lipid tails.
These cholesterol molecules help maintain membrane fluidity
Add carbohydrates to the outer layer of phospholipids.
These carbohydrates allow the cells to be recognized by other cells and molecules (and viruses yikes!)
Cholesterol
String = carbohydrate

73. Step 6: Nucleus Add your nucleus to the cell.
Is this cell a eukaryotic or prokaryotic cell? How do you know?
What does the nucleus hold in these cells?
Cotton ball = nucleus

74. Drawing out our cell membrane

75. What does the cell membrane do?
The cell membrane helps cells maintain homeostasis by allowing SOME things to enter/exit the cell and not others – it is SEMI- PERMEABLE

76. Questions:
If ANYTHING could freely move in and out of the membrane, would it still be called semi-permeable?
If NOTHING could move in and out of the membrane, would it still be called semi-permeable?

77. Semi-permeable Semi = Partially
Permeable = Allowing things to pass through
Semi-permeable means that some things can enter and leave while other things cannot

78. IS IT SEMI-PERMEABLE? ASK YOURSELF:
Yay = Thumbs up
Nay = Thumbs down
ASK YOURSELF:
Are only certain things able to go in and out? If yes, it is SEMI-PERMEABLE

79. The White House

80. Saya’s class during lunch…

81. An Exclusive Club

82. Quick check
What are two types of proteins that are part of the cell membrane? What are their functions?
What is it called when the cell membrane chooses to let certain things through, but not all things?

83. DNA 3/29/17 Peer Review Analysis Section (20 min)
If done early, work on study guide!

84. Outside… Draw a cell membrane w/ chalk. Make sure it has:
-phospholipid bilayer (make the circle have about a 4 meter diameter)
-protein channel (about 1.5 meters wide)
-protein receptor
-carbohydrate (you can name your team)
-cholesterol

85. What is Diffusion?
The tendency of molecules to move from HIGH concentration to LOW concentration
Molecules can diffuse in air and in liquids
NO energy required

86. Semi-permeable membrane

87. Semi-permeable membrane

88. Semi-permeable membrane

89. 3 ways things can pass through the cell membrane:
Diffusion is a form of transport through the cell membrane. There are 3 total. They are:
Simple Diffusion
Facilitated Diffusion
Active Transport

90. Simple Diffusion
Some molecules are small enough to pass through the lipid bilayer of the cell, including: oxygen, carbon dioxide, water and alcohol.
Molecules move from HIGH to LOW concentration without energy.
The diffusion of water is called osmosis

91. What is Facilitated Diffusion?
Some molecules are too BIG to pass through
These molecules need “carriers” to HELP them pass through
These carriers are PROTEINS
No energy required, molecules move from HIGH to LOW concentration

92. What can pass through the cell membrane?
Small things CAN pass:
O2 (Oxygen)
CO2 (carbon dioxide)
H2O (water)
Ethanol (alcohol)
Big things NEED HELP:
Glucose (sugar)
Amino acids
SIMPLE DIFFUSION!!!
Facilitated DIFFUSION!!!

93. What is Active Transport?
Active transport goes in the OPPOSITE direction of diffusion – molecules move from LOW concentration to HIGH
Requires ENERGY to move molecules against the concentration gradient

94. Transport: Use the “SLIDE” analogy

95. Answer with a partner What are the three types of diffusion?
What is the simple diffusion of water called?
Active transport moves molecules from ________ to _________ concentration.