Some vascular bundles are described as open. This is because they:

An annual ring consists of .........

The anatomy of springwood shows some peculiar features. Identify the correct set of statements about springwood.
$(a)$ It is also called as the earlywood
$(b)$ In spring season cambium produces xylem elements with narrow vessels
$(c)$ It is lighter in colour
$(d)$ The springwood along with autumnwood shows alternate concentric rings forming annual rings
$(e)$ It has lower density
Choose the correct answer from the options given below:

Tyloses,an outgrowth from ray or axial parenchyma cells into the lumen of a vessel,which partially or completely blocks the cavity,are present in:

In dicot stem,the cells of cambium present between the primary xylem and primary phloem is $..........$

Cork is the best material for making bottle stoppers because .....................