Unit 8 Flashcards
What is the function of the xylem
transport of water and mineral ions
also support of the plant
what is the function of the phloem
transport of sucrose and amino acids
what is the structure of the xylem
thick walls with lignin
no cell contents
cells joined end to end with no cross walls to form a long tube
how do large surface areas affect root hair cells
increases the uptake of water and mineral ions
what is the pathway of water taken through the plant
root hair cells, root cortex cells, xylem, mesophyll cells
what is transpiration
the loss of water vapour from leaves
how does water move through the leaf
evaporates from the surfaces of the mesophyll cells into the air spaces
diffused out the leaves through the stomata as water vapour
how does water move up in the xylem
there is a transpiration pull that draws up a column of water molecules
held together by forces of attraction between water molecules
what happens when there is higher temperature in terms of transpiration
the plant will lose more water since the particles will have more energy so they’ll diffuse faster
what effect does humidity have on transpiration
decreases the rate of transpiration since the gradient is lower and there is more moisture outside the plant
what is wilting
when the plant loses more water than its gaining
the plant cells become flaccid and the support of the plant reduces
what is translocation
the movement of sucrose and amino acids in phloem from sources to sinks
what is the source
the parts of plants that release sucrose or amino acids
what are sinks
the parts of plants that use or store sucrose or amino acids
why can some part of a plant act as a source and a sink
during growth, the plant leaf will be a source but also a sink as it uses energy to grow
during change of season some parts of a plant can change
