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The annular and spirally thickened condu...

The annular and spirally thickened conducting elements generally develop in the protoxylem when the root or stem is

A

maturing

B

elongating

C

widening

D

differentiating

Text Solution

Verified by Experts

The correct Answer is:
c
Vessels or tracheae are made up of a row of cells , placed one above the other , with their intervening walls absent or variously pored . The walls od vessels are lignified and hard but not very thick . The cell cavity or the lumen is wide . The thickening may be annular , spiral scalariform, reticulate and pitted.
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