b1 osmosis Flashcards
What is osmosis?
Osmosis is the movement of water molecules from an area of high concentration to an area of low concentration through a partially permeable membrane.
What is a partially permeable membrane?
A partially permeable membrane is a membrane that allows some molecules, like water, to pass through, but blocks others, like larger molecules.
What happens to plant cells when they are placed in water?
When plant cells are placed in water, water enters the cells by osmosis, causing them to swell. The cell wall prevents them from bursting, so they become turgid.
What does “turgid” mean in a plant cell?
Turgid” means the plant cell is swollen and firm because it is full of water, causing pressure against the cell wall.
What happens to animal cells when they are placed in water?
Animal cells may swell and burst if too much water enters them because they do not have a cell wall to protect them.
What is the term used to describe when a plant cell loses water?
When a plant cell loses water, it becomes plasmolysed, meaning the cell membrane pulls away from the cell wall.
What happens to a plant cell in a concentrated sugar solution?
In a concentrated sugar solution, water will move out of the plant cell by osmosis, causing the cell to shrink and become flaccid.
How does osmosis affect the size of a cell?
Osmosis can cause a cell to swell, shrink, or stay the same size depending on whether the surrounding solution is pure water, dilute, or concentrated.
What is the direction of water movement in osmosis?
Water moves from the area of lower solute concentration (higher water concentration) to the area of higher solute concentration (lower water concentration).
What is the role of osmosis in the human body?
Osmosis helps maintain the balance of water and salts in cells and tissues, which is important for processes like nutrient absorption and waste removal.
How can you observe osmosis in a potato?
You can observe osmosis in a potato by placing potato slices in different concentrations of sugar solution. The potato will either become firmer, softer, or change size depending on the concentration of the solution.
