Question

Kranz anatomy is found in
A. Most of monocots
B. Few dicots
C. Both A and B
D. None of the above.

Answer 1

Kranz anatomy is found in ${{C}_{4}}$ plants. ${{C}_{4}}$ plants include maize and common purslane and many other plants.

Step by step answer: The monocots are plants having two cotyledons and dicots are plants having to cotyledons, cotyledons are the structure which store food for the plants. The word Kranz means ring. Kranz anatomy is a specialized structure present in ${{C}_{4}}$ plants. In these plants, the mesophyll cells are accumulated around the bundle-sheath cells in a form of a ring. The numbers of chloroplasts in the bundle-sheath cells are more than those found in the mesophyll cells. The Kranz anatomy is developed in three different steps: Initiation of procambium, then bundle sheath and mesophyll cell specification, and lastly the chloroplast development and integration of the ${{C}_{4}}$ cycle.
In the ${{C}_{4}}$ plants, the light-dependent reactions, and the Calvin cycle are separated. The Calvin cycle takes place in the bundle-sheath cells whereas the light-dependent reactions occur in the mesophyll cells. These plants do not undergo photorespiration. The atmospheric oxygen is fixed to form 4-carbon compound oxaloacetate(OAA) in the mesophyll cells, catalyzed by the enzyme PEP carboxylase. Oxaloacetate is then converted to malate. Malate further dissociates in the bundle-sheath cells to release carbon dioxide gas which is converted into sugars. Due to a continuous process of this and a high concentration of carbon dioxide gas, photorespiration is reduced significantly.
Mostly, carbon dioxide is fixed into a 3 carbon compound by the action of the enzyme Ribulose bisphosphate carboxylase oxygenase in plants. RuBisCO is considered to catalyze a reaction with oxygen which gives a wasteful process known as photorespiration.
${{C}_{4}}$ plants include monocots and a few dicots.
Hence, the correct option is option C

Note: The process photorespiration is a waste of energy. It is a process causing severe loss of energy by using light energy in photosynthetic organisms to fix carbon for further carbohydrate synthesis.