The correct option is (c) 2 and 3 only.
Explanation
The epidermis is the outermost protective layer of the primary plant body. In roots, this layer is specifically adapted for the absorption of water and minerals from the soil and is often referred to as the epiblema or piliferous layer.
Statement-wise Analysis:
- Statement 1 is Incorrect. The primary function of the root epidermis is the absorption of water and minerals and protection of internal tissues. It does not perform photosynthesis because roots are typically underground, lack exposure to sunlight, and generally do not contain chloroplasts. Photosynthesis is the primary function of the mesophyll tissues in leaves.
- Statement 2 is Correct. The epidermal cells of the root commonly bear long, unicellular hair-like elongations known as root hairs. These structures greatly increase the surface area of the root system, maximizing the absorption of water and dissolved minerals from the soil.
- Statement 3 is Correct. The root epidermis lacks a cuticle. The cuticle is a waxy, impermeable layer found on the epidermis of stems and leaves to prevent water loss (transpiration). In roots, such a layer would obstruct the entry of water; therefore, the cuticle is absent to facilitate free movement of water into the root.
Key Takeaway:
The root epidermis is characterized by the presence of unicellular root hairs and the absence of a waxy cuticle, structural adaptations that maximize water and mineral absorption.