movement of molecules

Question 1

define osmosis

Answer 1

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

Question 2

define diffusion

Answer 2

the movement of particles from a high concentration to a low concentration across a partially permeable membrane

Question 3

define active transport

Answer 3

the movement of particles against a concentration gradient

Question 4

adaptations of exchange surfaces

Answer 4

thin
late sa
big blood supply

Question 5

how are leaves structures to allow gases to diffuse in and out

Answer 5

stomata, the leafs exchange surface, controlled by guard cells to open and close to allot for substances needed, preventing wilting

Question 6

diffusion of gases in photosynthesis

Answer 6

co2 diffuses in, oxygen and water vapour diffuse out

Question 7

how do the lungs let substances pass

Answer 7

lungs contain millions of air sacs called alveoli which are specialised to maximise the diffusion of oxygen to the blood and removing co2

Question 8

how does the small intestine let substances pass

Answer 8

covered in millions of villi, increasing the sa so good is digested quicker and can be diffused into the blood

Question 9

how are root hair cells specialised for active transport

Answer 9

large sa for the plant to absorb minerals from the soil, even though there are less minerals in the soil

Question 10

how does the blood get glucose through active transport

Answer 10

from the gut and kidney tubules it takes glucose