It's the gradual movement of particles from place where there are lots of them to places where there are lots of them to places where there are fewer of them.
1 of 16
What is the proper definition of diffusion?
It is the net (overall) movement of particles from an area of higher concentration to an area of lower concentration
2 of 16
Where does diffusion take place?
In liquids and gases
3 of 16
Why can diffusion happen in liquids and gases?
The particles in these substances are free to move about randomly
4 of 16
Only very small molecules can diffuse through what?
Cell membranes
5 of 16
Give examples of small molecules that can diffuse through cell membranes
Glucose, amino acids, water and oxygen
6 of 16
Give examples of big molecules that can't diffuse through cell membranes
Starch and proteins
7 of 16
What is the definition of Osmosis?
It is the net (overall) movement of water molecules across a partially permeable membrane from a region of higher water concentration to a region of lower water concentration
8 of 16
What is a partially permeable membrane?
It is a membrane with very small holes in it
9 of 16
In which direction do the water molecules move through the membrane?
Both ways
10 of 16
Why does this happen?
The water molecules move about randomly all the time
11 of 16
Why is there a steady net (overall) flow of water into the region with the fewer water molecules?
There are more water molecules on the other which means it is more likely to go through the membrane
12 of 16
What is the water trying to do to the concentration?
Even it up on either side of the membrane
13 of 16
How is active transport different from diffusion and osmosis? (2 things)
It works against the concentration gradient and it uses energy
14 of 16
What is the definition of active transport?
It is the movement of particles across a membrane against a concentration gradient using energy transferred during respiration
15 of 16
Give an example of active transport?
In our gut, nutrients going into the blood even if there is a higher concentration of nutrients in the blood
16 of 16
Other cards in this set
Card 2
Front
What is the proper definition of diffusion?
Back
It is the net (overall) movement of particles from an area of higher concentration to an area of lower concentration
Card 3
Front
Where does diffusion take place?
Back
Card 4
Front
Why can diffusion happen in liquids and gases?
Back
Card 5
Front
Only very small molecules can diffuse through what?
Comments
No comments have yet been made