Diffusion, osmosis and active transport Flashcards
what is diffusion?
movement of particles from a high concentration to a low concentration
What happens when there is a big difference in concentration?
there is a faster diffusion rate
What particles can go through the cell membrane?
small particles oxygen, amino acids, water, glucose, big molecules cannot fit through like starch and proteins
what is osmosis?
movement of water molecules across a partially permeable membrane from a region of higher water concentration to lower water concentration
What can and can’t pass through a partially permeable membrane?
big particles can’t but small particles can
How many ways can the water particles pass through?
both ways and they move randomly
What happens when there are more water particles on one side than the other?
There is a steady net flow of water in the region with fewer water molecules ie: into stronger solution
What happens to the stronger solution?
It becomes more dilute, water acts like it is trying to even up on each side of the membrane
what is active transport?
it is used in the digestive system when there is a low concentration of nutrients in the gut but high concentration of nutrients in the blood
What happens when there is a higher concentration of glucose and amino acids in the gut?
they diffuse into the blood
What happens if there is low concentration of nutrients in gut than in the blood?
this means concentration gradient is the wrong way but active transport allows us to transport nutrients into the blood even though it is the wrong way, stops us starving
what does active transport need?
energy so respiration for it to be able to work
what is another factor that effects the rate of diffusion?
the temprature, larger surface areas
