Question

Collenchyma occurs in
A. Herbaceous climbers
B. Woody climbers
C. Climbing sterns
D. Water plants

Answer 1

Collenchyma is extremely plastic cells that can extend and thus, increase the growth of the organ. This tissue is found chiefly within the cortex of stems and in leaves, and it is the primary supporting tissue for several herbaceous plants.

Complete answer: Collenchyma occurs in climbing sterns. It is a simple permanent tissue, which originates from elongated living cells having thickened pecto cellulosic walls. Collenchyma is a living mechanical tissue that provides both mechanical strength and elasticity and also permits them to grow in size. Collenchyma is found in the epidermis of a dicot stem and petioles and is abundant in climbing stems.
Collenchyma supports tissue in living and elongated cells which have irregular cell walls. Collenchyma cells contain thick deposits of cellulose in the cell walls which make them appear polygonal in cross-section. The strength of the tissue results from these thickened cell walls and also the longitudinal interlocking of the cells. Collenchyma cells are also found in cylinders or also occur as distinct strands. It is one amongst the three ground, or fundamental, tissues in plants, along with parenchyma (living thin-walled tissue) and sclerenchyma (dead support tissue with thick cell walls).
Hence, the correct answer is option C.

Additional Information: The first use of "collenchyma" was done by Link (1837), who used it to explain the sticky substance on Bletia (Orchidaceae) pollen. Schleiden in 1839 stated that the word "collenchyma" could be used to describe the elongated sub-epidermal cells which contain unevenly thickened cell walls.

Note: There are four main kinds of collenchyma:
i. Angular collenchyma (thickened at intercellular contact points).
ii. Tangential collenchyma (cells are arranged in sequential rows and are thickened at tangential faces of the cell wall).
iii. Annular collenchyma (uniformly thickened cell walls).
iv. Lacunar collenchyma (intercellular spaces are present).