xylem structure (1 Viewer)

[ribosome911]

So I read in some Bio books that the wall of xylem is lignified and therefore impermeable to water. But then as the pressure flow theory (which explains for the movement of materials in phloem) states that when the source is loaded with sugar, water is drawn in from the xylem by osmosis.
I just wonder how the water can cross the lignified wall of xylem and get into the phloem, since that wall is impermeable to water in the first place.
Any help is appreciated.
Thanks!

 

[ribosome911]

ok, I found the answer just yesterday!
Well probably I'm rather weird and gay here but I'm gonna post up the answer to my own question just in case someone is also wondering about it.

Xylem has pits (or pores) are what allow water to pass through its lignified wall. There are 2 types of pits : the first type occurs in the side wall of xylem and allow fluid to pass to nearby living cells, and the other one is intervessel pits that interconnect the adjacent xylem conduits and allow the horizontal movement of the water column!

 

[Jonneeh]

never remebered learning/needing to know any of that xD