Organising Plants Flashcards
Why is a leaf an organ
There are many tissues inside the leaf that work together to perform photosynthesis
How is the upper epidermis adapted for its function
Single layer of transparent cells allow light to pass through
Cells secrete a waxy substance that makes leaves waterproof
How is the palisade mesophyll adapted for its function
Tightly packed cells with lots of chloroplasts to absorb as much light as possible for photosynthesis
How is the spongy mesophyll adapted for its function
Air spaces increase the surface area and allow gases to diffuse quickly
What is the function of the guard cell
Control the opening and closing of the stomata
What is the function of the xylem
Transports water and mineral ions from the roots to the rest of the plant
Give three adaptation of the xylem
Made of dead cells
No end wall between cells
Walls strengthened by a chemical called lignin to withstand the pressure of the water
What is the function of the phloem
Transports dissolved sugars from the leaves to the rest of the plant
What is the purpose of translocation
Transports dissolved sugars from the leaves to other parts of the plant for respiration, growth and storage
Define the term transpiration
Movement of water from the roots to the leaves through the xylem
What is the purpose of transpiration
Provides water to cells for photosynthesis
Transports mineral ions to leaves
Name 4 factors that affect the rate of transpiration
Temp
Light intensity
Humidity
Wind speed
What effect does temp have on the rate of transpiration
Higher temp increases rate of transpiration
What effect does humidity have on the rate of tranpiration
Higher levels of humidity decrease the rate of transpiration
Why does increased light intensity increase the rate of transpiration
Stomata open wider to let more carbon dioxide into the leaf for photosynthesis
