Tracheids differ from the tracheary elements in:

1.	Having casparian strips	2.	Being imperforate
3.	Lacking nucleus	4.	Being lignified

Lenticels are involved in:

The common bottle cork is a product of:

1. dermatogen

2. phellogen

3. xylem

4. vascular cambium

Companion cells are closely associated with:

Closed vascular bundles lack:

1. Ground tissue

2. Conjuctive tissue

3. Cambium

4. Pith

Water containing cavities in vascular bundles are found in:

1. Sunflower

2. Maize

3. Cycas

4. Pinus

Gymnosperms are also called softwood spermatophytes because they lack:

1. Cambium

2. Phloem fibres

3. Thick-walled tracheids

4. Xylem fibres