The Cell Membrane

Question 1

What is the cell membrane

Answer 1

The cell membrane is a biological membrane that seperates the interior of all cells of the outside enviorment

Question 2

What is cholesterol and why is it important to the plasma membrane

Answer 2

Cholesterol is a sterol It is important because it helps maintain the rigidity of the cell membrane. Have too much and the cell is not permeable, have too little and the cell is too flexible

Question 3

What is a micelle?

Answer 3

Micells are lipid molocules that form in a spherical form.

Question 4

What is a lipid bilayer

Answer 4

The preferred structure of lipids in aqueous solutions. (Plasma membrane)

Question 5

What is a vesicle?

Answer 5

Lipid bilayer in spherical shape. AKA Transporters within the cell.

Question 6

Define the 5 different types of membrane proteins

Answer 6

1. Transmembrane - Span entirety of membrane, Usually function as gateways to permit substances across. 2. Intergral - Embedded within bilayer. 3. Peripheral - Attached to exterior of bilayer. Easily seperate off. 4. Associate Membrane Proteins 5. Anchored Membrane Proteins

Question 7

Define a membrane domain

Answer 7

The association of the lipid membrane with the cytoskeleton filaments and the ECM through membrane proteins.

Question 8

What is the most common type of Intergral Protein (IMP)

Answer 8

Transmembrane protein. There are multiple categories and they are based on how many times the TM passes the membrane

Question 9

Explain the different types of lipid bilayer movements a fatty acid can do in the bi layer

Answer 9

Lateral diffusion: Most common (uncatalyzed) -Flip Flopping (catalyzed)

Question 10

Answer 10

Question 11

What are the 3 general classes of membrane transport systems?

Answer 11

1. Uniport
2. Symport
3. Antiport

Question 12

What is membrane fusion and give an example

Answer 12

Membrane fusion is the process by which 2 seperate lipid bilayers merge and become 1.

Example: Sperm fusing with an egg

Question 13

What solutes are in simple diffusion?

Answer 13

Non polar compounds traveling DOWN concentration gradient

Question 14

Which type of membrane transport travels down electrochemical gradient NO ATP

Answer 14

Facilitated diffusion

Question 15

Membrane transport requires ATP & against electrochemical gradient?

Answer 15

Primary ACTIVE transport

Question 16

What it secondary active transport?

Answer 16

against electrochemical gradient, driven by ions movind down its gradient

Question 17

Describe an ion channel

Answer 17

Down electrochemical gradient, can be ligand gated or not.