xylem
Transports water and mineral ions from roots to leaves and provides support.
phloem
Transports sucrose and amino acids around the plant.
root hair cells
pathay of water
Root hair cells → root cortex cells → xylem → mesophyll cells
transpiration
loss of water vapour from leaves, mainly through the stomata
transpiration steps
Water is transported to the leaf through xylem ✔️
Water evaporates from mesophyll cell surfaces ✔️
Water vapour enters air spaces in the leaf ✔️
Water vapour diffuses out through stomata ✔️
factors affecting transpiration rate?
temp
wind speed
humidity
temperature in transpiration
More heat → faster evaporation ✔️
More kinetic energy → faster diffusion ✔️
wind speed
More heat → faster evaporation ✔️
More kinetic energy → faster diffusion ✔️
humidity in transpiration
High humidity → less difference in
water vapour concentration ✔️
Slower diffusion ✔️
wilting
Wilting occurs when water loss by transpiration exceeds water uptake by roots.
translocation
the movement of sucrose and amino acids in the phloem from sources to sinks.
sources
are parts of the plant that release sucrose or amino acids.
sinks
are parts of the plant that release sucrose or amino acids.
