Question

Which of the following plants, stand intermediate between $C_3$ and $C_4$ plants?

• A. Triticum aestivum
• B. Zea mays
• C. Panicum milioides
• D. All of the above

Answer 1

Answer: (C)

Panicum milioides

P. milloides is an intermediate between $C_3$ and $C_4$ plants as the activity of $C_4$ cycle enzymes is only 15 to 30% of a $C_4$ Panicum species and the Calvin cycle and phosphoenolpyruvate carboxylase are present in both cell types (bundle sheath and measophyll).As compared to a $C_3$ plants where only Calvin cycle takes place and $C_4$ plants where $C{O}_2$ is fixed in the mesophyll cells to a 4C compound OAA (Oxalo Acetic Acid) and is then moved into the bundle sheath cells where $C_3$ cycle takes place.

So, the correct answer is 'Panicum milioides'