Transpiration and photosynthesis Flashcards
What is transpiration?
Passive water loss through evaporation while stomata are open for gas exchange
What factors effect transpiration?
Temperature, wind speed, light exposure, and humidity
What is photosynthesis (and formula)?
Using sunlight to convert carbon dioxide and water into oxygen, glucose and water vapor
(CO2+H20»O2+C6H12O6+H20 vapor)
How does temperature affect the TR?
Increases - releases more water when warmer (like sweating)
How does wind speed affect the TR?
Increases - water carried away faster (dried out)
How does light intensity affect the TR?
Increases - stomata open in light (for photosynthesis)
How does humidity affect the TR?
Decreases - harder to evaporate into saturated air
What is the transpiration stream?
Upwards flow of water - from roots, through xylem to leaves
What is root pressure?
Force driving water upwards from the ground into the xylem
What is cohesion of water molecules?
Where molecules are attracted to one another, creating an upwards pulling force (in the xylem)
What are the functions of the xylem and phloem?
Xylem: transports water upwards
Phloem: transports nutrients throughout the plant (up and downwards)
What is translocation?
Movement of products of photosynthesis (glucose) from leaves to other cells within the plant (through phloem) for energy (to respirate, make new chemicals, or storage)
Extra: what tool is used to measure the TR?
A potometer
