Flashcards in Diffusion And Osmosis Deck (19):
The movement of a substance from a region of high to low concentration
How does water move in and out of plant cells?
By osmosis through the cell membrane
What is the purpose of a plant cell wall?
To provide support
What can a lack of water cause plants to do?
Where does water move in and out of animal cells?
Through the cell membrane
Describe how carbon dioxide and oxygen diffuse in and out if plants through the leaves
- The concentration of carbon dioxide outside the cell is greater than the concentration inside, so carbon dioxide diffuses into the cell
- The concentration of oxygen inside the cell is greater than the concentration inside, so oxygen diffuses out of the cell
Explain the net movement of particles by diffusion
From an area of high concentration to an area of low concentration, as a consequence of the random movement of individual particles.
Explain how the rate of diffusion is increased
- the particles have a shorter distance to travel
- the cell membrane's surface area is bigger
- there is a bigger difference between concentrations (a steeper concentration gradient)
How do substances move in and out cells by diffusion through the cell membrane?
By diffusion through the cell membrane
The movement of water across a partially-permeable membrane from an area of high water concentration to an area of low water concentration
What is osmosis?
A type of diffusion
Explain the term partially-permeable membrane
Membrane that allows only certain molecules or atoms through, graded by size
Explain how plants are supported by turgor pressure within cells
Water pressure activity ng against inelastic cell wall
Explain wilting in terms of a lack of turgor pressure
As the amount of water inside the cells reduces, the cells become less rigid due to reduced pressure
Describe the effects of the uptake and loss of water on animal cells
If too much water enters a cell it could burst
If too little water they shrivel up and become crenated
Explain the net movement of water molecules by osmosis
From an area of high water concentration to an area of low water concentration across a partially permeable membrane, as a consequence of the random movement of individual particles.
Explain the term flaccid
A plant cell that is limp through a reduction or pressure inside the cell
Explain the term plasmolysed
A plant cell that has lost water causing the cell membrane to be pulled away from the inside of the cell wall