Topic 2 Transpiration and translocation + Flashcards
What do phloems transport
Food substances (mainly dissolved sugars) made in the leaves to the rest of the plants for immediate use or for storage
What are phloems made of
Elongated cells with small pores in the end walls to allow cell sap to flow through
Separated by sieve plates
Which direction does the substances in the phloem flow
Both dirrections
What is it called if the liquid flows both ways
Translocation
What do xylems transport
Water and mineral ions
What are xylems made of
Dead cells joined end to end with no end walls between them and a hole down the middle
They are strengthened by lignin
Which direction does the water and mineral ions flow in the xylem
From the roots to the stem and leaves
What is the movement from the roots through the xylem and up to the leaves called
Transpiration stream
What is transpiration
The loss of water from the plant
What is transpiration caused by
The evaporation and diffusion of water from a plants surface
Where does most transpiration happen
The leaves
What is used to replace the shortage in water after evaporation
More water is drawn up through the xylem vessels to replace it
Why is there a constant stream of through the plant
Always a constant transpiration stream
What is transpiration a side effect of
The way leaves are adapted for photosynthesis
The leaves have a stomata so that gases can easily be exchanged
Because there is more water inside the plant than the air outside the water escapes from the leaves through the stomata by diffusion
