Unit 2 Multicellular Organisms 2.5 Flashcards
What is the function of the waxy cuticle in transport?
Waterproof layer to minimise water loss
What is the function of the upper epidermis in transport?
Protects the inner layers of cells and is transparent to allow light through
What is the function of the palisad mesophyll in transport?
Top layer of cells packed tightly together, containing many chloroplast for photosynthesis
What is the function of the spongy mesophyll in transport??
Cells arranged loosely with large air spaces between them to allow for diffusion of gases between cells
What is the function of a leaf vein in transport?
Contains xylem and phloem, to allow sugar and water to be transported in and out of the leaf
What is the function of the stoma (stomata) in transport?
Pores which are opened and closed to allow gases to move in and out.
What is the function of the guard cells in transport?
Found in either side of the stomata and changes their shape to open and close the pore.
What is the Function of the lower epidermis in transport?
Contains guard cells and small pores called stomata which allows gases in and out.
Stomatal movements?
Stomatal opening and closing is controlled by guard cells which are found in the lower leaf epidermis
Stomatal opening
Guard cells become turgid, thin outer cell walls stretch more than the thicker inner walls, stomatal pore to opening as inner walls pulled apart, open during daylight which allows water loss by transportation.
Stomatal closing?
Guard cells become flaccid, pore closes as guard cell is no longer bulge outwards,occurs during darkness and conserves water at night.
Xylem?
Transports water and minerals from roots to the leaves, dead tissue,Hallow tubes to allow movement, ring lignin to provide support, they are lignifies to withstand the pressure changed ad water moves through the plant.
Phloem?
Transports sugar to all part of the plant, living tissue, sieve tunes and companion cells, sieve plates allow rapid transport of sugar and the stands cytoplasm help to move sugar from one sieve tube to another.
Where are xylem and phloem found?
In the vascular tissue of a plant
What do you see in a root cross section?
Xylem tissue is grouped together to uptake water from the soil, phloem tissue is spread out to allow sugar to leave to be sent to all parts of the plant.
