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:

Wood is

The function of cork cambium $(phellogen)$ is to produce

Given below are two statements : One is labelled as Assertion $A$ and the other is labelled as Reason $R$:

Assertion $A$ : Late wood has fewer xylary elements with narrow vessels.

Reason $R$ : Cambium is less active in winters.

In the light of the above statements, choose the correct answer from the options given below :

What is correct for heartwood ?

Each of the following terms has some anatomical significance. What do these terms mean ? Explain with the help of line diagrams.

$(A)$ Plasmadesmoses / Plasmodesmata

$(B)$ Middle lamella

$(C)$ Secondary wall