Plant Growth and Development Question 62
62. Highest auxin concentration occurs
[1990]
(a) in growing tips
(b) in leaves
(c) at base of plant organs
(d) in xylem and phloem
Show Answer
Answer : a
Hints & Solutions
(a) Highest concentration of auxins occurs at the growing tips. This was proved by Went in 1928 by his experiment on Avena coleoptile. It was demonstrated that auxins are synthesized at the tips and then translocated downwards where they cause growth.
