Question: 112: Read the following statements about the vascular bundles :
(a) In roots, xylem and phloem in a vascular bundle are arranged in an alternate manner along the different radii.
(b) Conjoint closed vascular bundles do not possess cambium
(c) In open vascular bundles, cambium is present in between xylem and phloem
(d) The vascular bundles of dicotyledonous stem possess endarch protoxylem
(e) In monocotyledonous root, usually there are more than six xylem bundles present
Choose the correct answer form the options given below :
(1) (a), (b), (c) and (d) Only
(2) (a), (c), (d) and (e) Only
(3) (a), (b) and (d) Only
(4) None of these
Answer: None of these
Explanation:
In roots, vascular bundles are radial, with xylem and phloem arranged alternately along different radii,
so statement (a) is correct.
Conjoint closed vascular bundles lack cambium,
which is why secondary growth is absent in such bundles, making statement (b) correct.
In open vascular bundles, cambium is present between xylem and phloem and is responsible for secondary growth, so statement (c) is correct.
In dicotyledonous stems, the protoxylem is endarch, meaning it is directed towards the center,
hence statement (d) is correct.
Monocotyledonous roots usually show polyarch condition with more than six xylem bundles,
so statement (e) is also correct.
Since all five statements (a), (b), (c), (d), and (e) are correct,
and none of the given options includes all five statements,
the correct answer is none of these.