Question

Which ones are correct
(a) Uneven thickening of cell wall is characteristic of sclerenchyma
(b) Periblem forms cortex of stem and root
(c) Tracheids are chief water conducting elements in gymnosperms
(d) Companion cell is devoid of nucleus at maturity
(e) Commercial cork is obtained from Quercus suber

• A. b, c, e
• B. a, d
• C. b, e
• D. c, d
• E. a, b, c

Answer 1

Answer: (A)

b, c, e

Periblem: It is middle histogen which forms cortex of stem and roots. It is the central histogen which forms stele or part of stem and root inner to endodermis. Tracheids are the characteristic cells types of xylem tissue in gymnosperms and pteridophytes, where they are chief elements of water conduction. Cork, the outer bark of an evergreen type of oak tree called the cork oak (species Quercus suber) that is native to the mediterranean region.

So, the correct answer is 'b,c,e.'