Question

Kranz anatomy is seen in
A) Citrus indica
B) Zea mays
C) Euphorbia hirta
D) Mangifera indica

Answer 1

Kranz anatomy A specific structure in the leaves of plants which have a carbon dioxide fixation pathway.

Complete answer:
Two rings of cells are circling their vascular bundles-the inner ring, called the bundle sheath cells, contains starch-rich chloroplasts lacking grana, which vary from those present as the outer ring in mesophyll cells. Therefore, they are called dimorphic chloroplasts.Kranz anatomy's primary purpose is to provide a site where $CO_2$ is present.

It can be oriented around RuBisCO, thus preventing photorespiration. The boundary layer of the Kranz has a low conductance to $CO_2$ , a property that may be improved by the presence of suberin, in order to sustain a substantially higher $CO_2$ concentration in the bundle sheath compared with the mesophyll. The morphology of Kranz is typical of $C_4$ plants and maize is a $C_4$ plant.
In three general phases, the development of Kranz anatomy can be considered:

1. initiation of procambium;
2. BS and M cell specification;
3. Development of chloroplasts and incorporation of the $C_4$ cycle.

Kranz anatomy is a specialised structure around the bundle-sheath cells in plants where the mesophyll cells are clustered in a ring-like fashion. The number of chloroplasts in the bundle-sheath cells is more than the number in the mesophyll cells.

Thus the correct answer is option (B) Zea mays.

Note: Maize has become a staple food in many parts of the world, with annual maize production exceeding that of wheat or rice. In addition to being eaten directly by humans (often in the form of mass), maize is also used for corn ethanol, animal feed and other maize products, such as corn starch and corn syrup.