How do Plants support themselves?

[elwes]

I understand that lignin in dead tracheid cells form xylem vessels and helps give structure and support. But is their any other major factor that helps a plant stay upright? After all, in some trees hundreds of tonnes must need supporting by the trunk.

[Linn]

>roots anchor the tree

[SU_reptile]

Trees have a very thick cylinder of xylem that, as you said, gives them a great support. Plants have also their own supporting tissue in two forms, namely collenchyma and sclerenchyma. Their fibres are really strong and prevent a plant from being broken up.
I thonk turgidity of cells also may give some rate of stiffness.
Extensive rootsystem provides good anchorage in the soil.

[elwes]

thanks you, thats really helpful

[GIBSON_EXP]

i got his one. it has alot to do with turgor pressure. that is the pressure of water against the cell wall. when the plant it full hydrated turgor pressure is at its strongest. when it is dehydrated it tends to wilt.