Translocation and Transpiration

Question 1

What are PHLOEM tubes?

Answer 1

elongated living cells

with small pores at the end of walls to allow cell sap through

Question 2

What are XYLEM tubes?

Answer 2

dead cells
joined together at the end
no walls between them 
hollow 
strengthened by lignin

Question 3

What do PHLOEM do?

Answer 3

transport food substances (dissolved sugars/glucose) made in the leaves for immediate use or storage
transport is in both directions
called TRANSLOCATION

Question 4

What do XYLEM do?

Answer 4

transport water and mineral ions from the roots to the leaves and stem
transport in one direction
movement of water from roots through xylem out of leaves is called the TRANSPIRATION STREAM

Question 5

Explain the TRANSPIRATION STREAM

Answer 5

1) water evaporates off the surface of the plant usually through the leaves (transpiration)
2) this creates a shortage of water
3) more water is drawn up from the rest of the plant through the xylem vessels to replace it
4) more water is drawn up from the roots creating a constant stream

Question 6

Factor that affect the rate of TRANSPIRATION

Answer 6

LIGHT INTENSITY - brighter light means greater rate
TEMPERATURE - warmer means faster transpiration
AIR FLOW - better air flow/wind more transpiration
HUMIDITY - the drier the faster transpiration