Extrastelar secondary growth takes place by:
1.  Vascular cambium
2.  Phellogen
3.  Phellem
4.  Phelloderm

The periderm includes:
1.  Secondary phloem
2.  Cork
3.  Cambium
4.  All of these

Transition of exarch bundles of root to endarch bundles of stem occurs in:
1.  Epicotyl
2.  Hypocotyl
3.  Apical bud
4.  Coleoptile

The main function of lenticel is:
1. Transpiration
2. Guttation
3. Gaseous exchange
4. Bleeding

Vessels are found in:
 

Four radial V.B. are found in:
1.  Dicot root
2.  Monocot root
3.  Dicot stem
4.  Monocot stem

Which of the following statement is true:

1. Vessels are multicellular and with a wide lumen

2. Tracheids are multicellular and with a narrow lumen

3. Vessels are unicellular and with a narrow lumen

4. Tracheids are unicellular and with a wide lumen