Anatomy of Flowering Plants

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One-way

flow

Water and

minerals

No end walls

between cells

Stiffened with

lignin

Two-way

flow

Water and

food

End walls

with

perforations

Xylem

Phloem

A. Xylem

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It functions as a conducting tissue for water and minerals from roots to

the stem and leaves.

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It also provides mechanical strength to the plant parts.

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It is composed of 4 kinds of elements: tracheid’s, vessels, xylem fibres

and xylem parenchyma.

These are elongated tube-like dead cells with thick and

lignified walls and tapering ends. Protoplasm absent.

The inner layers of cell walls have thickenings which vary

in form. In flowering plants, tracheid’s & vessels are the

main water transporting elements. Cells are dead.

TRACHEIDS

It is a long cylindrical tube-like structure made up of

many cells (vessel members), each with lignified walls

and a large central cavity. Protoplasm absent, therefore

dead. Vessel members are inter-connected through

perforations in their common walls. The vessels are a

characteristic feature of angiosperms. Gymnosperms

lack vessels.

VESSEL