AP BIO cell transportation

Question 1

passive transport

Answer 1

Diffusion of a substance across a membrane with no energy investment

Question 2

Simple Diffusion

Answer 2

-The tendency for molecules to spread out evenly into the available space
-Molecules move from high to low concentration
-No energy or protein assistance needed

Question 3

Facilitated Diffusion

Answer 3

Transport proteins speed the passive movement of molecules across the plasma membrane

Question 4

Osmosis

Answer 4

-Diffusion of free water across a selectively permeable membrane
-Water moves towards higher solute concentration until the solute concentration is equal on both sides

Question 5

Transport Protein

Answer 5

-Provide passages that allow a specific molecule or ion to cross the membrane
(Specifically hydrophilic substances)
-Channel Proteins
(Hydrophilic channel that certain molecules or ions can use as a tunnel)
-Aquaporins
(Facilitate the passage of water)

Question 6

Carrier Protein

Answer 6

Binds to molecules and changes shape with allows the substances to follow through

Question 7

Active Transport

Answer 7

• Moves substances against their concentration gradients, usually requires energy as ATP
• Allows cells to maintain concentration gradients that differ from their surroundings
  (Ex: sodium-potassium pump)

Question 8

COTRANSPORT

Answer 8

When active transport of a solute indirectly drives transport of other solutes

Question 9

BULK TRANSPORT

Answer 9

Transports large molecules via vesicles

Question 10

ATP

Answer 10

-Adenosine triphosphate
-Composed of a ribose (sugar), adenine (nitrogenous base), and three phosphate groups
-Energy
-Used to make RNA

Question 11

Sodium-Potassium Pump

Answer 11

-A carrier protein that uses ATP to actively transport sodium ions out of a cell and potassium ions into the cell

Question 12

Steps of a Sodium-Potassium Pump

Answer 12

-Three sodium ions inside the cell bind to the pump protein
-The pump uses energy from ATP to change its shape
-The pump releases three sodium ions outside the cell
-Two potassium ions from outside the cell bind to the pump
-The pump returns to its original shape, releasing the two potassium ions in the cell

Question 13

Tonicity

Answer 13

The ability of a surrounding solution to cause a cell to gain or lose water

Question 14

Hypertonic

Answer 14

Solute concentration is greater than that inside the cell; cell loses water

Question 15

Hypotonic

Answer 15

Solute concentration is less than that inside the cell; cell gains water

Question 16

Isotonic

Answer 16

When the concentration of two solutions is the same, no net water movement

Question 17

Electrogenic Pump

Answer 17

-Transport protein that generates voltage across a membrane
Animals:
Sodium potassium pump
Plants, Fungi, Bacteria:
Proton pump

Question 18

Concentration Gradient (down vs. against)

Answer 18

-Difference in the concentration of a substance from one location to another
-Down:
From more to less concentrated
No energy is needed
-Against:
Requires work and energy

Question 19

Endocytosis

Answer 19

Cell takes in molecules and particulate matter by forming new vesicles from the plasma membrane

Question 20

Pinocytosis

Answer 20

• “Cellular Drinking”
• A type of endocytosis in which the cell ingests extracellular fluid and its dissolved solutes
• Used for liquid
  Small Vesicles

Question 21

Receptor Mediated

Answer 21

Receptor proteins on the cell membrane are used to capture specific target molecules and form a coated vesicle

Question 21

Phagocytosis

Answer 21

“Cellular Eating”
Used for solid materials
Large vesicles

Question 22

Exocytosis

Answer 22

• Transport vesicles migrate to the membrane, fuse with it, and release their contents
• Reverse of endocytosis
• Secretory cells use exocytosis to export products