The first stable product of CO2 fixation in C3 plants is a three-carbon organic acid. The enzyme ribulose-1,5-bisphosphate carboxylase–oxygenase (RUBISCO) combines CO2 with the phosphosugar ribulose 1,5-bisphosphate to form two molecules of 3-phosphoglyceric acid.

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The Light Reactions The energy is then temporarily transferred to two molecules, ATP and NADPH, which are used in the second stage of photosynthesis. ATP and NADPH are generated by two electron transport chains. During the light reactions, water is used and oxygen is produced.

The Calvin cycle refers to the light-independent reactions in photosynthesis that take place in three key steps. Although the Calvin Cycle is not directly dependent on light, it is indirectly dependent on light since the necessary energy carriers ( ATP and NADPH) are products of light-dependent reactions.

Products. The immediate products of one turn of the Calvin cycle are 2 glyceraldehyde-3-phosphate (G3P) molecules, 3 ADP, and 2 NADP+. (ADP and NADP+ are not really “products.” They are regenerated and later used again in the Light-dependent reactions). Each G3P molecule is composed of 3 carbons.

Photorespiration is absent in C4 plants due to the presence of a special structure called as kranz anatomy in their leaves. It is a process which takes place in C3 plants when carbon dioxide concentration in plants become low. Was this answer helpful?

The three types of plants are differentiated on the basis that in C3 plants the first stable product of photosynthesis is 3-carbon compound (phosphoglyceric acid) and in C4 plants, 4-carbon compound (oxaloacetic acid or malic acid) is the first stable compound.

In C3 carbon fixation, carbon dioxide first combines with a 3-carbon compound while in C4 carbon fixation, carbon dioxide first combines with a 4-carbon compound. Plant stomata are open during the day in both types of carbon fixation. In C3 plants, carbon fixation occurs throughout the leaf.

Terms in this set (3) In C3 plants, the first organic product of carbon fixation is a three-carbon compound, 3-phosphoglycerate. C4 plants incorporate carbon dioxide into malate, a four-carbon compound, before it enters the Calvin cycle. C4 and CAM plants use less water per carbon fixed than C3 plants.

In C4 photosynthesis, where a four-carbon compound is produced, unique leaf anatomy allows carbon dioxide to concentrate in ‘bundle sheath’ cells around Rubisco. C3 plants do not have the anatomic structure (no bundle sheath cells) nor the abundance of PEP carboxylase to avoid photorespiration like C4 plants.

What is the main adaptive advantage of the C4 and CAM photosynthesis strategy over the C3 strategy? They help the plant conserve water and synthesize glucose efficiently under hot, dry conditions.

The main difference between C4 and CAM plants is the way they minimize water loss. C4 plants relocate the CO2 molecules to minimize photorespiration while CAM plants choose when to extract CO2 from the environment. Photorespiration is a process that occurs in plants where oxygen is added to RuBP instead of CO2.

The disadvantage is when there is not a lot of light. The C4 shuttle enzymes consume energy in the form of ATP and NADPH. In areas of low light and low rates of photosynthesis, this becomes a disadvantage and gives C3 plants a competitive edge.

What is the primary advantage offered by the C4 and CAM pathways? C4 and CAM plants can close their stomata and save water without having to shut down photosynthesis.

The C4 pathway is certainly more efficient than the C3 pathway in carbon fixation. The enzyme responsible is RUBISCO (Ribulose 1, 5- bisphosphate). In C4 plants, the inner cells get only carbon dioxide in the form of malate. This avoids the oxygenation process and, hence, makes this pathway more efficient.