The light-colored outer region of the wood is known as ..........

In a stem which is covered by periderm and in which stomata are absent,gaseous exchange takes place through

Select the wrong statement regarding secondary phloem.

Annual rings and growth rings are formed due to the fluctuation in the activity of .......... .

In cambium,the amount of secondary xylem produced is more than secondary phloem because..........

Select the correct statement$(s)$:
$(1)$ Lenticels are absent in woody climbers.
$(2)$ Lenticels are found in most woody trees.
$(3)$ Spring wood is lighter in color and has a lower density.
$(4)$ Sapwood is also known as duramen (heartwood).