Why do plants need transport systems?
- Because a lot of multicellular organisms like plants hve a high surface area:volume ratio simple diffusion would be too slow a proccess to use to get all the necissary nutrients to relevant parts of the plant.
- transpot water and mineral ions
- move from roots to leaves
- very long and tube-like
- joined end to end without end walls to interupt the flow of water
- cells are dead thus containing no cytoplasm
- cell WALLS are impregnated with lignin
- lignin is either deposited in spirals or complete rings which allows flexibility and stops the stem from breaking
- as the cell gets older the ammount of lignin increases
- there are pits in the cell wall where there is no lignin present…