SB8a Efficient Transport and Exchange

Question 1

Diffusion?

Answer 1

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

Question 2

What would speed up the rate of diffusion? (4)

Answer 2

.large surface area
.good blood supply
.thin membrane
.bigger concentration gradient

Question 3

Explain the need for a transport system in multicellular organisms.

Answer 3

.it would take too long for materials to diffuse through cells on the outside of a tissue to reach cells inside
.transport systems are more efficient

Question 4

Explain the need for exchange surfaces (large surface area) in multicellular organisms.

Answer 4

the larger the surface area, the more of a substance can diffuse in a certain time.

Question 5

How is surface area : volume ration worked out?

Answer 5

surface area/volume

Question 6

How are alveoli adapted for gas exchange by diffusion between air in the lungs and blood in capillaries?

Answer 6

.the lungs are packed with millions of alveoli, which increase the surface area - increase the speed of gas exchange