transport

Question 1

what its diffusion?

Answer 1

the passive movement of particles from a high concentration to a low concentration

Question 2

how can you change the rate of difussion?

Answer 2

by altering concentration gradient, temperature and surface area

Question 3

for multicellular organisms, what are the surfaces and organ systems specialised for?

Answer 3

exchanging materials

Question 4

how can the effectiveness of an exchange surface be increased?

Answer 4

i. Having a large surface area
ii. Thin membrane
iii. Efficient blood supply (in animals)
iv. Being ventilated (in animals for gas exchange)

Question 5

what is osmosis?

Answer 5

the passive movement of water from an area of higher water concentration to an area of lower water concentration, across a partially permeable membrane

Question 6

what are mass changes caused by?

Answer 6

by the movement of water across a plant cell membrane

Question 7

what is active transport?

Answer 7

uses energy from respiration, to transport substances across a membrane from low concentration to high concentration

Question 8

what is active transport used in?

Answer 8

in root hair cells and the small intestine for the absorption
of nutrients