Diffusion, Osmosis and Active Transport Flashcards
Fill the blanks:
Diffusion is the net movement of _________ from a ____ concentration to the opposite.
Osmosis is the movement of _____ from a ____ concentration to the opposite.
Active Transport is the movement of _________ from a ____ concentration to the opposite
Particles High Water High Particles Low
Which one(s) is/ are passive transport? Why?
Diffusion and osmosis, because neither require energy
Give the definition of osmosis
Osmosis is the movement of water particles from a high concentration of water to a low concentration of water through a partially permeable membrane. It requires no energy
Why does active diffusion need energy?
To flip the protein carriers (as it goes against the concentration gradient)
Give the definition of diffusion
Diffusion is the net movement of particles from a high concentration to a low concentration
What are the two factors which affect the rate of diffusion?
The temperature (higher = faster) The concentration difference (bigger difference = faster)
What is the definition of these words? And which form of transport does this relate to?
a) Hypertonic
b) Hypotonic
c) Isotonic
Osmosis - water
a) When there is a higher concentration outside a cell, so the particles go into the cell
b) When there is a higher concentration inside the cell, so the particles go out of the cell
c) When the concentration of water is equal in and out of the cell
With equal chunks of a potato, I put one into a test tube of pure water (1). I put the other in a test tube of salt water (2). After 24 hours, which one will weigh more?
1 will, because the potato has a lower concentration of water in its cells, so the pure water outside will enter the cell through osmosis - this is hypertonic. It will then weigh more as there is more water in the potato chunk.
2 won’t, because the salt in the solution makes outside the cells of the potato a lower concentration. So, the remaining water from inside the potato cells will leave through osmosis - this is hypotonic
Why does active transport need protein carriers?
Because the ions that it transports are too big to diffuse through the cell membrane
Diffusion transports what sort of particles?
Dissolved substances (for example, urea, glucose and gases)
Complete the sentence:
Exchange surfaces usually have…
A large surface area, thin cell walls and an efficient blood supply
Root hair cells use which type of transport and why?
Active transport, so that it can absorb ions from the soil
Complete the sentence:
Active transport allows sugar molecules to be…
Absorbed in the gut
Single cell organisms have a relatively small Surface Area to Volume ratio. True or False?
False - they have a relatively large SA:V ration
