Osmosis Flashcards
What is transpiration?
Transpiration is the process of evaporation of water from mesophyll cells in leaves, followed by diffusion through airspaces and stomata
How does surface area affect transpiration?
A larger surface area increases the rate of transpiration because larger leaves will have more stomata which they can lose water
What role does wind play in transpiration?
wind increases transpiration rate as water lost by transpiration will be carried away quicly therefore renewing the diffusion gradient
How does temperature influence transpiration?
Higher temperatures increase the rate of transpiration as they enhance water evaporation from leaf surfaces.
What is the effect of humidity on transpiration?
Higher humidity levels decrease the rate of transpiration because the concentration gradient between the inside of the leaf and the outside air is reduced.
How does light intensity affect transpiration?
Increased light intensity stimulates stomatal opening, which can lead to higher rates of transpiration due to increased photosynthesis and water vapor loss.
leads to stomata opening
higher transpiration due to higher photosynthesis
leading to water vapor loss
What are the main uses of water in plants?
Plants use water for support, transport of nutrients, transpiration, and photosynthesis.
What is osmosis?
Osmosis is the diffusion of water molecules from a dilute solution to a more concentrated solution through a selectively permeable membrane
How does osmosis affect plant cells?
Osmosis can cause plant cells to become turgid when water enters the cell, or plasmolysed when water exits the cell.
What happens to a plant cell when it becomes turgid?
Cyptoplasm would increase in size
cell membrane would push up against the cell
What is plasmolysis in plant cells?
Plasmolysis occurs when water leaves the plant cell, causing the cell membrane to pull away from the cell wall, resulting in a shriveled appearance.
What role does the cell wall play in osmosis?
The cell wall limits the entry of water
How does a selectively permeable membrane function in osmosis?
A selectively permeable membrane allows water molecules to pass through while restricting the movement of solutes, facilitating the process of osmosis.
What structural changes occur in turgid plant cells?
In turgid plant cells, the cell membrane pushes against the rigid cell wall, resulting in a firm and swollen appearance that provides structural support.
What happens to the cell wall during turgidity?
cell wall stops the plant cells absorbing more water, provides more support to the cell
swollen shape
What structural changes occur in plasmolysed plant cells?
In plasmolysed cells, the cell membrane detaches from the cell wall, causing the cell to shrink and leading to a gap between the cell membrane and the cell wall.
How does the appearance of a plasmolysed cell differ from a turgid cell?
A plasmolysed cell appears shriveled and may have a reduced volume, while a turgid cell appears swollen and firm.
What is the effect of osmosis on the vacuole in turgid and plasmolysed cells?
In turgid cells, the vacuole is full of water, contributing to cell pressure, while in plasmolysed cells, the vacuole loses water, leading to cell shrinkage.
What happens to the cytoplasm in a plasmolysed cell?
In a plasmolysed cell, the cytoplasm shrinks away from the cell wall due to water loss, resulting in a gap between the cytoplasm and the cell wall.
