Bio U1 - 1.3

Question 1

What are Phospholipids

Answer 1

They are major components of cells and they are formed by the smooth endoplasmatic reticulum

Question 2

State the primary function of the cell membrane.

Answer 2

The cell membrane regulates the movement of substances in and out of the cell

Question 3

Contrast the structure of integral and peripheral proteins.

Answer 3

Integral: they are embedded in the phospholipid bilayer
Peripheral: they are loosly connected to the membrane

Question 4

List the 5 functions of membrane bound proteins.

Answer 4

1. Channel
2. Carrier (Changes shape)
3. Recognition
4. Receptor
5. Enzyme

Question 5

State an example of Channel proteins

Answer 5

Cl ions

Question 6

State an example of Carrier Proteins

Answer 6

Glucose

Question 7

State an example of Recognition Proteins

Answer 7

Glycoproteins (blood type)

Question 8

State an example of a Receptor Proteins

Answer 8

Hormones

Question 9

State an example of a Enzyme Proteins

Answer 9

In the mitochondria (atp synthase)

Question 10

What is cholestrol in the cell membrane made of and what is its function?

Answer 10

Modulate membrane fluidity by making it less fluid and permeability to some solutes. 4 hydrocarbon rings and a head. It is amphipathic.

Question 11

How does temperature impact the function of Cholesterol molecules

Answer 11

In colder temperatures, it disrupts the packing and solidification of the phospholipids as they can cannot pack together because of the cholesterol molecules.
In hotter temperatures, cholesterol provides structure to the membrane so it does not move as much.

Question 12

Describe Cholesterol’s polarity

Answer 12

Cholesterol has both positively and negatively charged areas, thus it is amphipathic