Question

Which of the following is a secondary meristem?
a. Protoderm
b. Procambium
c. Cork cambium
d. All of the above

Answer 1

Hint: secondary meristem is a type of tissue responsible for secondary growth such as growth in thickness, where it is different from primary growth tissue where there is growth in height or length

Complete answer:
Cork cambium is a tissue found in many plants .
> It is found as a part of epidermis of plants
> It is usually found in between the primary phloem and cork
> It is responsible for the lateral growth of the plant.
> It is usually found in dicot plants as secondary growth is commonly seen in them.
> Both vascular cambium and cork cambium is considered as secondary meristems
> Where vascular cambium is produced in stem and roots, where they form a woody tissue.
> The cork cambium usually forms a bark tissue.
> Secondary phloem is also a part of the bark of the woody plant, as we know secondary phloem usually develops from secondary cambium.
> They usually arises as a concentric layer
> This cork cambium is also called as phellam which usually forms outside the stem
> Suberin is the dead material usually found in the phellam , it helps the stem from water loss and as well as from mechanical damage.
> As the tree grows ,the bark layer increases which increases the circumference of the tree.
> As the plants develops additional cork cambium arises from the secondary phloem
> Where as other options such as procambium and Protoderm come under primary meristems

From the above explanation the answer is cork cambium.

Note: In dicots there will be secondary growth, where the secondary meristem arise, it is a permanent tissue which is usually arise and form the secondary tissue such as cork cambium and vascular cambium