Question

Cladode is
A. One internode long modified stem capable of photosynthesis
B. A specialized reproductive shoot
C. Flattened green stem of unlimited growth
D. A perennial fleshy underground stem

Answer 1

Hint: Cladode is a modified stem that makes it behave as a leaf assuming its photosynthetic activity. The stem becomes photosynthetic and functions as a leaf. The stem becomes flat. Cladode formation is evident in Asparagus. The cladodes have limited growth and one or two internodes are present on their surface.

Complete step by step answer: A cladode is a flat modified stem having leaves being modified as spines or there are no leaves at all. This modified stem is called phylloclade. So, cladode can be defined as a phylloclade that is succulent in nature. The modified stems are succulent and consist of one or two internodes. This modification can be seen in Opuntia, Euphorbia, and Cactus.
-Option A: It is one internode long modified stem capable of photosynthesis as it takes up the function of a leaf.
-Option B: The flattened stem does take up the function of photosynthesis but it is not a reproductive type of modified shoot.
-Option C: The specialized shoot has a limited growth rate that is one or two internodes long.
-Option D: It is not a fleshy stem rather it is flattened. Also, it is not situated underground.
So, the correct option is option A.

Note: The terms phylloclade and cladode are confused sometimes. But the phylloclade is defined as a subset of cladodes that greatly resemble the function of leaves. Also, cladodes are distinguished from phylloclades by their limited growth. Phylloclade is characterized by multiple nodes and internodes.