2.3 transport in stems Flashcards
what transports water and minerals to leaf, and essentially passive
xylem
what transports sap from leaves to growing or non-photosynthetic tissue
phloem
what are collenchyma cells
cells with thin primary walls that provide cylindrical support for plants
What is unstable about pith
extremely large cells that may collapse
how is sugar loaded into sieve tubes
vie the companion cell
how is the sugar transported through sieve tubes
high and low pressure. the sap flows from areas of high pressure to low pressure
what is the name of the pore that allows sucrose into the sieve tube
plasmodesmata
how is sucrose pumped into the companion cell
an H+ gradient is made outside the companion cell, and when the H+ flows back in, the sugar is brought in as well
anatomy of xylem in conifers
tracheids that are long and connected by bordering pits (allow water to pass to cells)
what tropical tree has huge vessel elements
lianas
How is xylem transport of water passive
The transport is fueled by evaporation in leaves, where the water the leaved in the leaves causes a pressure that pulls more water up to take its place
how can the bordered pits be of further help in transporting water
they can bypass embolisms
what is the inside of a bordered pit in xylem stems called
torus
what does procambium form in its second year
cambium
what does cambium produce annually
layer of phloem (outside) and xylem (inside)
