Osmosis Flashcards
Define osmosis
the movement of water molecules from an area of high water potential(concentration) to an area of low water potential(concentration) across a selectively permeable membrane
In which direction does osmosis occur from an area of H20 and salt and an area of H20
In which direction does osmosis occur from an area of 40% H20and 60% salt and an area of 30% H20 and 70% salt?
In which direction does osmosis occur from an area of 10% sugar and an area of 25% sugar?
In which direction does osmosis occur from an area of 65% sugar and an area of 65% sugar?
there is no net movement
A bag made from a semi-permeable membrane is tied to a glass tube and filled with a strong sugar solution. The bag is placed in a weak sugar solution. What will happen and why?
Water will move into the visking tube because there is a high water potential outside of the visking tube and a low water potential inside. Osmosis occurs from a high to low water potential.
A bag made from a semi-permeable membrane is tied to a glass tube and filled with a weak sugar solution. The bag is placed in a strong sugar solution. What will happen and why?
Water will move outisde of the visking tube into the area around it. This is because there is a high water potential inside the visking tube and a low water potential outside. Osmosis occurs from high to low water potential.
Explain the solute concentration in cells
cytoplasm contains water, sout, organic molecules
vacuole contains cell sap (water, amino acids, salt, glucose)
A piece of potato is placed into a beaker with water. What will happen and why?
the potato cells become turgid because water goes into the potato by osmosis
water potential is lower in potato
A piece of potato is placed into a beaker with 50% sugar. What will happen and why?
the potato cells become flacid because they lose water by osmosis
water potential is higher in potato
A peice of potato is placed into a beaker with 20% of sugar. What will happen and why?
the potato cells become flacid because they lose water by osmosis
less flacid than 50%
What happens to plant cells inside a solution with a very high sugar concentration?
water leaves cell by osmosis
cytoplasm and vacuole shrink (cell becomes plasmolysed)
flacid cells are plasmolysed
-i.e. the membrane gets pulled away from the cell wall as water is lost
What happens to animal cells inside a solution with a very high sugar concentration?
water leaves cell by osmosis
cell shrinks and becomes flaccid
What happens to plant cells inside a solution with a very low sugar?
water enters cell by osmosis
cytoplasm and vaculoe swell
plant cells become turgid when they take in a lot of water
What happens to animal cells inside a solution with a very low sugar concentration?
water enters cell by osmosis
cell swells and might burst
Summary of osmosis
