Dear Student
a) The intercellular spaces are absent in sclerenchyma and the closely arranged cells offer strength and protection to the plant parts. The intercellular spaces in the tissue are absent and hence the cells appear to be polygonal in transverse section.
b) The branches of trees move and bend freely in wind because the branches of the tress have collenchyma cells. Collenchyma is a very flexible tissue. It gives mechanical strength and support to the plant body. It also provides elasticity to plants causing it to bend when the wind velocity is high without breaking the branch.
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