Osmosis Flashcards
Define osmosis.
Osmosis is the diffusion of water molecules from a high water potential to a region of low water potential across a partially permeable membrane.
How does water move in and out of a cell?
In and out by osmosis through a partially permeable membrane in a concentration gradient.
What does the concentration gradient in osmosis mean?
The concentration gradient means the difference in water potential.
What happens when water enters a plant cell?
- The vacuole gets bigger, pushing the cell membrane against the cell wall.
- Cell becomes rigid and firm
Why is osmosis important for the plant cells?
- The effect of all the calls in a plant being firm is to provide support and strength for the plant - making the plant stand upright with its leaves held out to catch the sunlight.
What happens to the cell when too much water is there?
The pressure created by the cell wall stops too much water from entering and prevents the cell from bursting.
What will happen if the plant cells are placed in a concentrated solution (with a lower water potential than inside the cell)?
water molecules will move out of the plant cells by osmosis, making them feel flaccid.
What will happen if a plant cell becomes flaccid?
It can negatively affect the plants ability to support itself.
What will the cell look like if put under a microscope with less water in the cell?
It will look plasmolyzed meaning the cell membrane has pulled away from the cell wall.
What happens when plant cells are placed in a solution that has High water potential (dilute solution) than inside the cell?
Water moves into the plant cell via osmosis.
What is an example of a dilute solution?
Distilled water
What happens when water enters the cell?
The water molecules push the cell membrane against the cell wall, increasing the turgor pressure in the cells which makes them turgid.
What is one part the animal cell does not hv in comparison to plant cells
Animal cells do not have a supporting cell wall, so the result on the cell is more severe.
What will happen if an animal cell is placed in a strong sugar solution (with a lower water potential than the cell) ?
it will lose water by osmosis and become crenated (shriveled up)
What happens if animal cells are placed into distilled water (with a higher water potential than cell)
It will gain water by osmosis, as it has no cell wall to create turgor pressure, and will continue to do so until the cell membrane is stretched too far until it bursts.
