chapter 2 - movement of substances

Question 1

define diffusion

Answer 1

diffusion is the net movement of particles from a region of higher concentration to a region of lower concentration, down a concentration gradient.

Question 2

define concentration gradient

Answer 2

it is the difference in concentration between two regions

Question 3

what is the framework for diffusion?

Answer 3

1. Concentration
2. Direction of movement of particles
3. Diffusion

Question 4

The blood has a ______________ concentration of carbon dioxide compared to the alveolus. Thus, the carbon dioxide molecules move from the _________________ into the _____________ via _____________.

Answer 4

higher,
blood in the blood capillaries,
alveolus,
diffusion

Question 5

The air in the alveolus has a ______________ concentration of oxygen compared to the red blood cells. Thus, the oxygen molecules move from the _________________ into the _____________ via _____________.

Answer 5

higher,
alveolus,
red blood cells,
diffusion

Question 6

what are the four factors that affect the rate of diffusion?

Answer 6

1. diffusion distance
2. concentration gradient
3. surface area-to-volume ratio
4. temperature

Question 7

define osmosis

Answer 7

osmosis is the net movement of water molecules from a region of higher water potential to a region of lower water potential, down a concentration gradient.

Question 8

what is the framework for osmosis?

Answer 8

1. Compare water potential
2. Osmosis
3. Direction of movement of water molecules
4. Effect

Question 9

when an animal cell has a higher water potential than solution, the solution is _______ to cytoplasm of cell, leading to a net movement of water molecules out of the cell via ____________. As more water molecules leave the cell, the cell _________ and ________________.

Answer 9

hypertonic, osmosis, shrinks, becomes crenated

Question 10

when an animal cell has a lower water potential than solution, the solution is _______ to cytoplasm of cells, leading to a net movement of water molecules into the cell via ____________. As more water molecules enter the cytoplasm of the cell, the cell _________ and ________________.

Answer 10

hypotonic, osmosis, swells, bursts

Question 11

when an animal cell has the same water potential as the solution, the solution is _______ to cytoplasm of cell, leading to NO net movement of water molecules into or out of the cell via ____________.

Answer 11

isotonic, osmosis

Question 12

when the cell sap in the plant cell has a higher water potential than solution, the solution is _______ to cell sap of plant cells, leading to a net movement of water molecules out of the plant cell via ____________. As more water molecules leave the cell, the cell _________ and ________________. When too many water molecules leave the plant cell, the cell membrane _______________ from the cell wall and the cell becomes ___________.

Answer 12

hypertonic, osmosis, shrinks, becomes flaccid, pulls away, plasmolysed

Question 13

when the cell sap in the plant cell has a lower water potential than solution, the solution is _______ to cell sap of plant cells, leading to a net movement of water molecules into the plant cell via ____________. As more water molecules enter the cell, the plant cell _________ and ______________. The cell wall prevents the cell from ___________.

Answer 13

hypotonic, osmosis, swells, becomes turgid, bursting

Question 14

define active transport

Answer 14

-net movement of particles against a concentration gradient
-from a region of lower concentration to a region of higher concentration
-across a partially permeable membrane
-energy is required for this process