1.3 Cell transport Flashcards
(15 cards)
whats diffusion
Diffusion is the net movement of particles from an area of higher concentration to an area of lower concentration.
what does a higher concentration mean?
where particles are more closer together
In which direction will diffusion take place between area A and area B
if B has more particles that are closer together
than A which has particles that are farther apart
justify your answer
B—> A
as particles move from a higher concentration to a lower one and b is higher concentrated therefore it goes from b to a
what does a lower concentration mean?
where particles are farther apart
In which of the following states can molecules diffuse?
(Select all that apply)
Liquid
Solid
Gas
liquid and gas
Cell membranes are said to be ‘partially permeable’. What does this mean?
Only some molecules can pass through the membrane
Which molecules are able to diffuse into and out of cells?
amino acids
water
starch
protein
glucose
Justify your answer
amino acids, water and glucose
Only small molecules such as water, glucose, and amino acids, can diffuse into/out of cells.
Large molecules like proteins and starch are too big.
List 4 factors that affect the rate of diffusion.
Concentration gradient
Temperature
Surface area
Distance to diffuse across (if diffusing across a membrane)
Will a larger surface area increase or decrease the rate of diffusion?
Justify your answer:
Increase
Decrease
increase
A larger surface area means a larger area over which molecules can diffuse.
Why does a higher temperature increase the rate of diffusion?
Higher temperature means particles have more (kinetic) energy
So they move around faster
And can diffuse more quickly
What does it mean by saying diffusion is a ‘‘passive’’ process
means it does not require energy form the cell
Whats a concentration gradient
the difference in concentration between two places
The bigger the concentration gradient ____ diffusion occurs.
This is because..
And this helps cells get…?
the faster diffusion occurs
The larger the concentration gradient the higher the rate of diffusion
This helps cells get oxygen and nutrients
The higher the temperature the ___ diffusion occurs.
This is because..
Faster
Higher temperatures give the particles more energy
The larger the surface area the ____ diffusion occurs.
Faster
More surface area means more space for particles to diffusion
