Diffusion and Osmosis

Question 1

diffusion

Answer 1

the movement of molecules from a region of high concentration to a region of low concentration

Question 2

osmosis

Answer 2

the movement of water across a semi permeable membrane from a region of high water concentration to a region of low water concentration

Question 3

passive transport

Answer 3

does not require energy

Question 4

does osmosis require energy

Answer 4

no

Question 5

permeable

Answer 5

let everything in and out (cell wall)

Question 6

semi permeable

Answer 6

let some things in and out (cell membrane, vacuole)

Question 7

impermeable

Answer 7

let nothing in and out

Question 8

active transport

Answer 8

movement of molecules against a concentration gradient which requires energy

Question 9

osmoregulation

Answer 9

the control or balance of water and salt levels in an organism

Question 10

plasmolysis

Answer 10

the loss of turgor pressure in a plant cell due to the loss of water by osmosis

Question 11

turgor pressure

Answer 11

pressure of the cell contents eg vacuole and cell membrane against the cell wall

Question 12

turgid

Answer 12

a plant cell in which the cell contents are pushing against the cell wall due to turgor pressure

Question 13

animal cells in a less concentrated solution

Answer 13

if there is more water outside than inside the cell

the water from the outside will move into the cell and may cause it to burst or die

Question 14

animal cells in a more concentrated solution

Answer 14

if there is more water in their cytoplasm than in the solution outside

the water may leave the animal cell and the cells shrivel up and may die

Question 15

osmosis and food preservation

Answer 15

1. food is placed in a sugary or salty solution to preserve it
2. any bacteria or fungi try to grow/reproduce = can’t
3. their cell surroundings have a higher solute concentration so water moves out of their cells by osmosis
4. cells shrivel up and die

eg fish in salty solution
jam

Question 16

if a plant cell is surrounded by a less concentrated solution

Answer 16

how roots absorb water by osmosis
1. water moves in by osmosis
2. vacuole fills and swells
3. cytoplasm and vacuole push against cell wall = turgor pressure
4. cell is turgid
eg lettuce

Question 17

if a plant cell is surrounded by a more concentrated solution

Answer 17

1. water moves out by osmosis
2. vacuole and cytoplasm shrivel
3. move away from cell membrane
4. solution fills the space between membrane + wall
5. cell is flaccid - plasmolysis