Explain the mechanism of the C 4 cycle.

The C 4 pathway acts as a mechanism to build up high concentrations of carbon dioxide in the chloroplasts of the bundle sheath cells. The mechanism takes place as follows: The C 4 pathway initiates with a molecule called phosphoenolpyruvate (PEP) which is a 3-carbon molecule. This is the primary CO 2 acceptor and the carboxylation takes place with the help of an enzyme called PEP carboxylase. They yield a 4-C molecule called oxaloacetic acid (OAA). This is converted into another 4-carbon compound known as malic acid. Later, they are transferred from mesophyll cells to bundle sheath cells. Here, OAA is broken down to yield carbon dioxide and a 3-C molecule. The CO 2 thus formed is utilised in the Calvin cycle whereas the 3-C molecule is transferred back to mesophyll cells for regeneration of PEP.

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Embibe Experts Solutions for Exercise 1: Rajasthan Board-2020

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Embibe Experts Biology Solutions for Exercise - Embibe Experts Solutions for Exercise 1: Rajasthan Board-2020

Attempt the practice questions from Exercise 1: Rajasthan Board-2020 with hints and solutions to strengthen your understanding. EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR BIOLOGY solutions are prepared by Experienced Embibe Experts.