Exchange surfaces in the body

Question 1

Define diffusion

Answer 1

the movement of particles
from a region of higher
concentration of that
particle to a region of
lower concentration of
that particle

Question 2

Concentration gradient

Answer 2

The difference in
concentration that
drives diffusion is called
a concentration
gradient

Question 3

Layer of moisture

Answer 3

Allows substances like oxygen and carbon dioxide to dissolve and
diffuse easily across the membrane

Question 4

Single layer of epithelial cells (thin barrier)

Answer 4

Small distance for substances to move.
Decreases the time it takes for substances to
diffuse from one area to another

Question 5

Large surface area

Answer 5

Exchange surfaces have a large
surface area.

E.g. the lungs have millions of
individual alveoli that combined have
a huge surface area. Large amounts
oxygen and carbon dioxide can
diffuse across this surface area
simultaneously

Question 6

Main organs of exchange

Answer 6

Kidney - Urea, water, salts
Lungs - co2, o2, h2o
Intestine - water, amino acids, sugars, fatty acids, glycerol