Transport Mechanism

Question 1

Components of Plasma Membrane

Answer 1

Phospholipids
Cholesterol
Integral proteins
Peripheral proteins
Carbohydrates

Question 2

The main fabric of plasma membrane

Answer 2

Phospholipids

Question 3

Between phospholipids and phospholipids bilayers

Answer 3

Cholesterol

Question 4

Embedded between phospholipid layers

Answer 4

Integral proteins

Question 5

Inner or outer surface of the phospholipid bilayer

Answer 5

Peripheral proteins

Question 6

Attached to proteins on outside membrane layers

Answer 6

Carbohydrates

Question 7

Molecules with a hydrophilic head and a hydrophobic tail

Answer 7

Phospholipids

Question 8

attract water containing different molecules, and so making them close to the cell membrane

Answer 8

Hydrophilic heads

Question 9

prevent hydrophilic substances like salt, sugar, starch, or cellulose to easily pass through the cell membrane

Answer 9

Hydrophobic tails

Question 10

Present between the phospholipids
❖ Regulates the fluidity of the plasma membrane
❖ Gives extra support to cell membrane in the absence of cell wall

Answer 10

Cholesterol

Question 11

responsible for moving chemicals and ions across the membrane

Answer 11

Integral proteins

Question 12

receptors for
hormones, recognition centers, and antigens

Answer 12

Peripheral proteins

Question 13

❖ sites of cell recognition and adhesion, either cell-cell recognition or cell-pathogen interactions
❖ they also have the ability to trigger immunological responses

Answer 13

Carbohydrates

Question 14

Factors Affecting the Fluidity of Plasma Membrane

Answer 14

Temperature
Cholesterol
Saturated and unsaturated fatty acids

Question 15

It involves the movement of molecules from higher concentration to lower concentration and no amount of energy is required.

Answer 15

Passive transport

Question 16

Movement of particles from high to low concentration

Answer 16

Diffusion

Question 17

Types of diffusion

Answer 17

Simple diffusion
Facilitated dffusion

Question 18

Movement of solvent from low to high solute concentration

Answer 18

Osmosis

Question 19

It uses energy to move solutes against their gradients. This is possible by the movement of solutes by transport protein. This transport is “uphill” and therefore requires work.

Answer 19

Active transport

Question 20

Examples of active transport

Answer 20

Sodium-potassium pump
Bulk transport

Question 21

• most important pump in the
  animal cell
• Transports sodium ions (Na+)
  out of the cell, and potassium
  ions (K+) into the cell
• This is critical for neurons to
  be able to fire action potentials

Answer 21

Sodium-potassium pump

Question 22

a mode of transport of large quantities of materials and food particles across the membrane

Answer 22

Bulk transport

Question 23

It is the process by which cells take in substances from outside of the cell by engulfing them in a vesicle.

Answer 23

Endocytosis

Question 24

3 Types of Endocytosis:

Answer 24

Phagocytosis
Pinocytosis
Receptor-mediated endocytosis

Question 25

the bulk absorption of solid material (cell-eating process)

Answer 25

Phagocytosis

Question 26

the bulk uptake of liquid material (cell- drinking process)

Answer 26

Pinocytosis

Question 27

receptor proteins on the cell surface are used to capture a specific target molecule

Answer 27

Receptor-mediated endocytosis

Question 28

❖ a form of bulk transport during which large numbers of molecules are transported out of the cell
❖ This process is important for the removal of waste, for chemical messaging between cells, and for rebuilding the cell membrane

Answer 28

Exocytosis

Question 29

as temperature cools down, membranes switch from a fluid state to a solid state.

Answer 29

Temperature

Question 30

at high temperatures, cholesterol acts to stabilize the cell membrane and increase its melting point; while at low temperatures, it inserts into phospholipids and prevents them from interfering with each other to avoid aggregation

Answer 30

Cholesterol

Question 31

Membranes rich in unsaturated fatty acids are more fluid than those rich in saturated fatty acids

Answer 31

Saturated and unsaturated fatty acids

Question 32

is any external solution that has a higher solute concentration than what’s inside the cell.

Answer 32

Hypertonic solution

Question 33

is any external solution that has the same solute concentration as that inside the cell.

Answer 33

Isotonic solution

Question 34

solution is any external solution that has a lower solute concentration than what’s inside the cell.

Answer 34

Hypotonic solution