The balloon-shaped structures called tyloses
1. are linked to the ascent of sap through xylem vessels
2. originate in the lumen of vessels
3. characterize the sapwood
4. are extensions of xylem parenchyma cells into vessels

The terminal and axillary buds arise from

Which of the following is true about tracheids and vessels
1. Tracheids are multicellular with narrow lumen
2. Tracheids are unicellular with wide lumen
3. Vessels are multicellular with wide lumen
4. Vessels are unicellular with narrow lumen

Common feature in vessel elements and sieve tube elements is

The length of different internodes in a culm of sugarcane is variable because of
1. Size of leaf lamina at the node below each internode
2. Intercalary meristem
3. Shoot apical meristem
4. Position of axillary buds

The annular and spirally thickened conducting elements generally develop in the protoxylem when the root or stem is

Given below is the diagram of a stomatal apparatus. In which of the following, all the four parts labelled as A, B, C and D are correctly identified:

Some vascular bundles are described as open because these
1. are surrounded by pericycle but no endodermis
2. are capable of producing secondary xylem and phloem
3. possess conjunctive tissue between xylem and phloem
4. are not surrounded by pericycle

Water containing cavities in vascular bundles are found in

Anatomically, fairly old dicotyledonous root is distinguished from the dicotyledonous stem by
1. Position of protoxylem
2. Absence of secondary xylem
3. Absence of secondary phloem
4. Presence of cortex