Cell Transport Mechanisms

Question 1

What is diffusion?

Answer 1

The movement of particles down a concentration gradient, they move from a high concentration to a low concentration

Question 2

What is facilitated diffusion?

Answer 2

Diffusion that takes place through carrier proteins or protein channels

Question 3

What is osmosis?

Answer 3

A type of diffusion that involves the movement of water molecules down a concentration gradient through a semi-permeable membrane

Question 4

What is endocytosis?

Answer 4

The movement of large molecules into cells through vesicle formation

Question 5

What is exocytosis?

Answer 5

The movement of large molecules out of cells through vesicle formation

Question 6

What is active transport?

Answer 6

The movement of substances across the membrane of cells using ATP

Question 7

What is an isotonic solution?

Answer 7

Normal cells, the osmotic concentration of the solutes is the same as the cells

Question 8

What is a hypertonic solution?

Answer 8

Shrivelled cells where the water has left, the osmotic concentration of the cells is lower than in the solutes

Question 9

What is a hypotonic solution?

Answer 9

The cells swell and eventually burst, the osmotic concentration in the solutes is lower than in the cells

Question 10

What does turgid mean?

Answer 10

Hard, swollen (hypotonic cells)

Question 11

What does flaccid mean?

Answer 11

Space between vacuole and cell wall (isotonic cells)

Question 12

What is water potential?

Answer 12

A measure of the potential of water to move out of a solution by osmosis

Question 13

What is turgor?

Answer 13

The state of a plant cell when the solute potential causing water to be moved into the cell by osmosis is balanced by the force of the cell wall pressing on the protoplasm

Question 14

What is plasmolysis?

Answer 14

When a plant cell is placed in hypertonic solution when so much water leaves the cell by osmosis that the vacuole

Question 15

What is the calculation for water potential?

Answer 15

Turgor pressure + osmotic potential

Question 16

What factors affect active transport?

Answer 16

-Temperature
-pH levels
-Concentration gradients
-Availability of ATP

Question 17

What is phagocytosis?

Answer 17

A form of active transport where a cell engulfs something relatively large e.g a bacterium and encloses it as a vesicle

Question 18

What is pinocytosis?

Answer 18

A form of active transport where cells take tiny amounts of extracellular fluid into vesicles

Question 19

What is turgor pressure?

Answer 19

The pressure generated as the swelling protoplasm pushes against the cell wall in plants

Question 20

What is a carrier protein?

Answer 20

Proteins which move a substance through the membrane in active transport

Question 21

What is pressure potential?

Answer 21

A measure of the inward pressure exerted by the plant cell wall on the protoplasm of a cell opposing the entry of water by osmosis

Question 22

What is passive transport?

Answer 22

Transport that takes place as a result of concentration, pressure or electrochemical gradients and involves no energy from a cell

Question 23

What are the differences between passive transport and active transport?

Answer 23

-Passive transport diffuses from high to low
-Passive transport includes osmosis
-Passive transport requires no energy
-Active transport includes engulfing a transport protein
-Active transport diffuses low to high
-Active transport requires energy

Question 24

What is the definition of osmosis about water potential?

Answer 24

The net movement of water molecules from an area of higher water potential to an area of lower water potential through a partially permeable membrane