Question

In Kranz anatomy, the bundle sheath cells have

• A. thin walls, many intercellular spaces and no chloroplasts.
• B. thick walls, no intercellulai spaces and large number of chloroplasts.
• C. thin walls, no intercellular spaces and several chloroplasts.
• D. thick walls, many intercellular spaces and few chloroplasts.

Hint:

The bundle sheath cells, the leaf cell type, are a layer of cells that is present in the leaves and stems of plants and that forms a tightly packed layer surrounding the veins. The Kranz anatomy is a specialized structure in C₄ plants where the mesophyll cells are clustered around the bundle-sheath cells. It is a structure having a ring-like fashion.

Answer 1

The Correct Option is B

The correct answer is option B, thick walls, no intercellulai spaces and large number of chloroplasts.

The C₄ plants that are adapted to dry tropical regions have greater productivity of biomass. They possess a special type of leaf anatomy which is known as Kranz anatomy. The bundle sheath cells, in such anatomy, form several layers around the vascular bundles. These cells are characterized by having a large number of chloroplasts, thick walls impervious to gaseous exchange, and no intercellular spaces.

Therefore, In Kranz's anatomy, the bundle sheath cells have thick walls, no intercellulai spaces and large number of chloroplasts.

Answer 2

C₄ plants are those that go through the photosynthesis process using the C₄ photosynthesis mechanism. C₄ plants include many Angiosperm species, grasses, and hedges. The Kranz anatomy describes how the mesophyll cells surround the bundle sheath cells. Plant leaves and stems have a layer of cells known as bundle sheath cells. These cells wrap the vascular bundles in a sheath. The bundle sheath cells contain chloroplasts and are important Calvin cycle sites. C₄ photosynthesis is mediated by the bundle sheath cells.
 
The mechanism of photosynthesis. Photosynthesis products are transported from these cells to the surrounding phloem tissue. The products are then transferred to other areas of the plant via the vascular tissues. The bundle sheath cells differ greatly from the mesophyll cells. The bundle sheath cells have very tiny, poorly formed grana. The bundle sheath cells contain a large number of starch granules. Bundle sheath cells have thicker walls than mesophyll cells. In addition, there are no intercellular gaps in the bundle sheath cells. Bundle sheath cells contain a significant number of chloroplasts because they have internalized Rubisco, which aids in carbon-dioxide fixation.