Cell transport Flashcards
Diffusion definition
Particle net movement from a higher concentration to a lower concentration
They move down the concentration gradient
It is not a passive process
Examples are:
When carbon dioxide diffuses from the blood in the capillaries into the air in the alveoli
Osmosis definition
From a dilute solution to a concentrated solution through a partially permeable membrane
Moves from a lower solute concentration to a higher solute concentration
No passive process
Examples are:
A concentrated solution in the root hair cell
Active transport definition
Movement of particles froma more dilute solution to a more concentrated solution using energy from respiration
The particles move against the concetration gradient low to high concentration
Yes- energy released by respration
Examples are:
Allows sugar molecules to be absorbed from the small intestine when the sugar concentration is higher in the blood
Villi in the small intestine
For absorbing nutrients
Good blood supply
Thin wall ( only one cell thick)
Large surface area due to folding ( more efficient absorption of fatty acids and glycerol into the blood stream)
Network of cappillaries ( good blood supply)
Factors that can effect rate of diffusion
Steeper the concentration gradient, the faster the rate of diffusion
The higher the temperature, the faster the rate of diffusion
The larger the membrane surface area, the faster the rate of diffusion
Alveoli in the lungs
For gas exchange
Network of caplliaries provides a good blood supply
Rate of diffusion increased in membrane since:
Has a large surface area
Is moist
Is only one cell thick ( short diffusion pathway)
Fish gills
For gas exchange
Fish gills are made of stacks of thin filaments with:
Alarge surface area to increase diffusion
A network of capillaries ( good blood supply)
Root hair cells
For uptake of water and minerals
Lots of mitchondria to take in mineral ions by active transport
Large surface area helps with efficient absorption of water and mineral ions
