Question

Cortex is formed from
a. Cambium
b. Procambium
c. Ground meristem
d. Protoderm

Answer 1

Hint: Cortex comprises the unspecialized cells which lie in between the epidermis and the vascular tissues of the stem and roots. These cells are meant for storage. They may contain carbohydrates or other secondary metabolites like resins, latex, oils and tannins.

Complete answer:
We are already aware of the storage property and the location of the cortex. Let us discuss its origin.

Cortex is the outer layer of the stem or root in the plants. The cells of the cortex are structurally undifferentiated and are made up of large thin-walled parenchyma cells. The outer cortical cells are irregular and have thick cell walls and are called collenchyma cells. It forms the layer of the cells which forms the cork. The outermost cells may have chloroplast.

Cambium- the cambium is the secondary meristem that is formed after the primary differentiation of stems and roots in the plant. These are responsible for increasing the girth of the plant and also formation of bark.

Procambium- The procambium comprises the meristematic tissues which form the vascular system i.e. xylem and phloem. They form new vascular tissue in mature stem and roots.

Ground meristem- It comprises parenchyma, collenchyma.
Protoderm- It gives rise to the epidermis. Its primary function is to protect the plant from mechanical injury.

As the cortex is made up of parenchyma and collenchyma which are ground meristem.
Hence the correct answer is option (c).

Note: The sclerenchyma is made up of dead cells. The walls of these cells are thickened with lignin and cellulose. They provide mechanical and structural support to the plant.