Organisation - Plant Tissues
What are the layers of a leaf from top to bottom?
-Waxy cuticle
-Upper epidermis
-Palisade mesophyll
-Spongy mesophyll
-Lower epidermis
-Waxy cuticle
What is the palisade mesophyll?
the layer of cells containing lots of chloroplasts to absorb light for photosynthesis
What is the upper epidermis?
the layer of transparent tissue to let light through to the plaisade layer
What is the lower epidermis?
Layer that contains stomata pores to allow gases amd water vapour to enter/exit the lead
What do the guard cells do?
control the opening and closing of the stomata; they must balance the need to open for gas exchange with the prevention of water loss through transpiration
What is the phloem and what does it do?
A tissue that contains specialised cells that are adapted for transporting the products of photsynthesis (sugars, amino acids) around the plant from the leaves. This is know as translocation.
What is the transpiration stream?
the flow of water from the roots to leaves
What is the xylem?
A tissue made of specialised cells that are adapted for the transport of water and mineral ions
What adaptations do xylem have for the transport of water and mineral ions?
-One way flow
-Thick cells walls made of lignin
-Cells having no end walls between them
What adaptations do the phloem have for the transport of the products of photosynthesis around the plant?
-Two way flow of sap
-Cells with end walls and perforations
-Thick cell walls made of cellulose