Cell Membrane

Question 1

What is the cell membrane?

Answer 1

The cell membrane controls what enters and exists the cell, it is a semi-permeable subject made of a phospholipid bylayer embedded with proteins.

Question 2

Phospholipid bilayer

Answer 2

• 2 layers
• made of a phosphate head which is polar and hydrophilic
• made of a fatty acid tail which is non-polar and hydrophobic
• Includes channel, carrier, recognition and receptor proteins

Question 3

Fluid mosaic model

Answer 3

Fluid - flowing freely

mosaic pattern which the embedded proteins make

Question 4

Intracellular

Answer 4

Inside the cell

Question 5

Extracellular

Answer 5

Outside the cell

Question 6

Channel proteins function:

Answer 6

Passive diffusion

Question 7

Carrier proteins function:

Answer 7

facilitated diffusion

Question 8

Active Transport

Answer 8

Move substances from an area of low to high concentration

- carrier protein

Question 9

Passive transport

Answer 9

Moves substances from an area of high concentration to an area of low concentration
- Channel protein

Question 10

Osmosis

Answer 10

• Movement of water

- Occurs through aquaporins (channel proteins)

Question 11

Exocytosis

Answer 11

The movement of molecules out of the cell in vesicles that release their contents to the outside of the cell

Question 12

Endocytosis

Answer 12

a mode of active transport where cell engulf extracellular molecules

• Phagocytosis: solids enter the cell
• Pinocytosis: liquids enter the cell

Question 13

What factors affect exchange:

Answer 13

• Physical properties
• Electro-chemical properties
• Concentration gradient
• Surface area to Volume ratio

Question 14

Isotonic:

Answer 14

Equal amount of solute on both sides

Question 15

Hypertonic:

Answer 15

Less solute on the inside compared to the outside

- cell with shrink

Question 16

Hypotonic:

Answer 16

Less solute on the outside compared to the inside

- cell will increase or burst

Question 17

Factors that affect the rate that material can move over a membrane

Answer 17

• Surface area to volume
• concentration
• Size
• charge
• Temperature

Question 18

Active modes of transport

Answer 18

Active transport
endocytosis
exocytosis
pinocytosis
Phagocytosis

Question 19

Phagocytosis

Answer 19

The process by which a cell surrounds and takes in solid particles

Question 20

Pinocytosis

Answer 20

The process by which cells enfold, and take in, drops of liquid

Question 21

Exocystosis

Answer 21

the process by which the contents of the vesicles of the cells are pushed out through the cell membrane

Question 22

Is the head of the bilayer hydrophilic or hydrophobic.

Answer 22

Tail = hydrophobic
Head = hydrophilic