Lesson 1: Gas exchange Flashcards
What is the function of the waxy cuticle on leaves?
To form an impermeable barrier that reduces water loss.
What is the function of palisade mesophyl?
It is packed with chloroplasts for photosynthesis.
What is the function of spongy mesophyl?
Has air spaces for gas exchange.
What is the function of the xylem?
transports water and minerals
What is the function of the phloem?
Transports products of photosynthesis
Why does transpiration occur in plants?
Because stomata must open for gas exchange during photsynthesis, causing water vapour loss.
What are the benefits of transpiration?
Cools the plant, helps mineral uptake, and maintains turgor pressure.
What environmental factors affect the rate of transpiration?
Air movement, temperature, light intensity, and humidity.
Outline the process of transpiration.
The loss of water creates negative pressure in the leaves which pulls on water molecules in the xylem up in a process called capillary action.
