Osmosis & Transpiration 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 selectively permeable membrane.
True or False: Osmosis is a type of passive transport.
True
What is the driving force behind osmosis?
The concentration gradient of solute particles.
Fill in the blank: Osmosis results in the equalization of __________ across a membrane.
solute concentration
What is transpiration?
Transpiration is the process by which water is lost from a plant through evaporation from the leaves.
True or False: Transpiration helps to cool the plant and facilitate nutrient uptake.
True
What is the role of stomata in transpiration?
Stomata are small openings on the surface of leaves that allow for gas exchange and water loss during transpiration.
What environmental factors can affect the rate of transpiration?
Factors such as temperature, humidity, wind, and light intensity.
How does transpiration contribute to the movement of water in plants?
Transpiration creates a negative pressure that pulls water up through the plant’s xylem vessels.
What is the cohesion-tension theory?
The cohesion-tension theory explains how water moves through plants due to the cohesive properties of water molecules and tension created by transpiration.
True or False: Transpiration helps to maintain the water balance in plants.
True
What is the main function of the xylem in plants?
The xylem transports water and minerals from the roots to the rest of the plant.
How does the process of plasmolysis relate to osmosis?
Plasmolysis occurs when a plant cell loses water and the cell membrane pulls away from the cell wall due to osmotic water loss.
What is the difference between hypertonic, hypotonic, and isotonic solutions in relation to osmosis?
Hypertonic solutions have a higher solute concentration, hypotonic solutions have a lower solute concentration, and isotonic solutions have an equal solute concentration compared to the cell.
How does the process of turgor pressure relate to osmosis in plant cells?
Turgor pressure is the pressure exerted by the cell contents against the cell wall, and it is maintained by the entry of water into the cell through osmosis.
What is the importance of the cuticle in transpiration?
The cuticle is a waxy layer on the surface of leaves that helps reduce water loss during transpiration.
What is the role of guard cells in regulating transpiration?
Guard cells control the opening and closing of stomata to regulate the exchange of gases and water vapor during transpiration.
How does the process of tension-cohesion theory explain water movement in plants?
The tension-cohesion theory states that water is pulled up through the xylem vessels due to the cohesive properties of water molecules and tension created by transpiration.
What part of a bubble potometer is used to reset the experiment?
The reservoir
How is transpiration measured using a bubble potometer?
Transpiration is calculated by measuring the movement of a small air bubble up the capillary tube and towards the plant.
What does a bubble potometer actually calculate.
Total water uptake of the plant
How does humidity affect transpiration?
As humidity increases, the rate of transpiration decreases due to a decrease in the severity of the concentration gradient.
How does wind affect transpiration?
As wind speed increases, the rate of transpiration increases with it. This is because water vapour is moved on faster, increasing the concentration gradient.
What happens to a plant cell in a hypertonic solution?
Water moves into the cell through osmosis, causing it to become turgid.
What happens to a plant cell in a concentrated solution.
Water leaves the cell, causing it to become either flaccid or plasmolysed.
