Question

Mechanical tissue is best developed in
A. Hydrophytes
B. Halophytes
C. Xerophytes
D. Mesophytes

Answer 1

The tissue that protects a plant and its growing organs against any deformation and provides mechanical strength is defined as mechanical tissue. The tissue system ensures the sturdiness of a plant, that is, its ability to withstand such static and dynamic stresses as the force of gravity and wind gusts.

Complete step-by-step answer:
hydrophytes refers to plants that grow in water. In floating or submerged hydrophytes, mechanical tissues are poorly formed or absent, because the buoyancy aspect of water protects them from physical injuries. Generally, the body of the plant comprises elongated and loosely organized spongy cells. When turgid, these thin-walled cells provide the plants with mechanical support. Therefore, option A is wrong.
Halophytes refer to plants that grow in saline water or soil which has high salinity. Mechanical tissues are not best developed in them as they grow in water and do not face some major injuries. Therefore, option B is wrong.
Plants that survive in dry environments are known as xerophytes. To thrive in dry environments, these plants show many morphological and structural adaptations. The mechanical tissue is well-formed in the stem and bark is also well developed to preserve water. Therefore, option C is the correct answer.
Mesophytes refers to plants whose growth can occur in both dry and wet conditions. The presence of mechanical tissues in mesophytes is not much developed. Therefore, option D is wrong.

So, option C) is the correct option.

Note: Collenchyma, sclerenchyma, brachysclereids, sonic fibers (in the secondary cortex), and libriform fibers are mechanical tissues. Substantial thickening of cell membranes, firm bonds between cells, and elasticity of membranes, as well as the precise distribution of mechanical tissues in the plant, ensure the key functions of the mechanical tissues. Collenchyma is one of the essential mechanical cells of the rising organs and the mature organs of herbaceous plants.