Q. Consider the following statements and choose the correct option. I.The thread like cytoplasmic strands, running from one cell to other is known as plasmodesmata. II.Xylem and phloem constitute the vascular bundle of the stem. III.The first formed xylem elements are described as metaxylem. IV.Radial vascular bundles are mainly found in the leaves.
A) I is true, but II, III and IV are false
B) II is true, but I, III and IV are false
C) III is true, but I, II and IV are false
D) I and II are true, but III and IV are wrong
Explanation
Plasmodesmata are thread-like cytoplasmic strands running from one cell to other and these make connection between adjacent cells. Each vascular bundle is made up necessarily of xylem and phloem elements and the cambium may or may not be present. The first differentiated xylem is called protoxylem, whereas those differentiated afterwards are called metaxylem. Radial vascular bundles are mainly found in the roots. In these, there are separate and alternate strands of phloem and xylem present on different radii.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.