How do c3 and c4 plants differ in their capacity for photosynthesis?

Asked By: Hadhoum Eizenstein | Last Updated: 13th January, 2020
Category: business and finance biotech and biomedical industry
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In C3 plants, the carbon dioxide fixation takes place only at one place. In C4 plants, the carbon dioxide fixation takes places twice (one in mesophyll cells, second in bundle sheath cells). C3 plants possess only one CO2 acceptor. C4 plants possess two CO2 acceptors (primary acceptor and secondary acceptor).

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Similarly, it is asked, how does a c4 plant differ from a c3 plant?

C3 plants are those plants where the first product of photosynthesis is a 3 carbon compound i.e. phosphoglyceric acid (PGA) while C4 plants are those plants where the first product of photosynthesis is a 4 carbon compound i.e oxaloacetic acid (OAA).

Likewise, why are c4 plants more efficient in photosynthesis? The C4 pathway is certainly more efficient than the C3 pathway in the sense of carbon fixation. The enzyme responsible for this step is RuBisCO. 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.

Likewise, people ask, why do c4 plants show more efficient photosynthesis as compared to c3 plants?

In C3 plants, chloroplasts are not present in the bundle sheath cells. Also, In C4 plants, photosynthesis occurs even when pores called stomata are closed. C4 plants show high efficiency in photosynthesis than the C3 plants because they contain more chloroplasts.

How are c3 c4 and CAM plants similar?

Cells involved in a C3 pathway are mesophyll cells and to that of the C4 pathway are mesophyll cell, bundle sheath cells, but CAM follows both C3 and C4 in same mesophyll cells. C3 can be seen in all photosynthetic plants, while C4 is followed by tropical plants and CAM by Semi-arid condition plants.

37 Related Question Answers Found

What are examples of c3 plants?

About 85% of plant species are C3 plants. They include the cereal grains: wheat, rice, barley, oats. Peanuts, cotton, sugar beets, tobacco, spinach, soybeans, and most trees are C3 plants. Most lawn grasses such as rye and fescue are C3 plants.

What characteristic gives c3 and c4 plants their names?

  • C3 Plants. The C3 pathway gets its name from the first molecule produced in the cycle (a 3-carbon molecule) called 3-phosphoglyceric acid.
  • C4 Plants. The C4 process is also known as the Hatch-Slack pathway and is named for the 4-carbon intermediate molecules that are produced, malic acid or aspartic acid.
  • CAM Plants.

What are some examples of c4 plants?

Examples of C4 Plants
Examples of C4 species are the economically important crops corn or maize (Zea mays), sugarcane (Saccharum officinarum), sorghum (Sorghum bicolor), and millets, as well as the switchgrass (Panicum virganum) which has been utilized as a source of biofuel.

What is an example of a c3 plant?

Most plants are C3 plants and some examples include: evergreen trees, deciduous trees and weedy plants like lambs quarters and bindweed. Important crop plants like rice, barley and soybean are also C3. Many plants that live in the tropics and subtropics, where precipitation is not sparse, are C3 plants.

What do you mean by c4 plants?


A C4 plant is a plant that cycles carbon dioxide into four-carbon sugar compounds to enter into the Calvin cycle. These plants are very efficient in hot, dry climates and make a lot of energy. Many foods we eat are C4 plants, like corn, pineapple, and sugar cane.

What is the advantage of c4 plants?

The advantages of C4 Photosynthesis include no photorespiration, CO2 fixation is resistant to heat and drought, higher water use efficiency.

How are c4 and CAM plants different?

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.

What is meant by a c3 plant?

C3 plants are plants in which the initial product of the assimilation of carbon dioxide through photosynthesis is 3-phosphoglycerate, which contains 3 carbon atoms.

What is the advantage of c4 plants over c3 plants?

Plants that perform C4 photosynthesis can keep their stomata closed more than their C3 equivalents because they are more efficient in incorporation CO2. This minimizes their water loss. Although C4 photosynthesis is clearly advantageous in hot and dry climates, this is not true in cool and moist ones.

Why do c4 plants are more expensive than c3 plants?


Photosynthesis in Higher Plants. How is C4 pathway more energy expensive that C3 ? C3 Cycle needs 18 ATP molecules for synthesis of one molecule of glucose whereas the C4 cycle needs 30 ATP molecules. Due to high energy requirement C4 cycle is more energy expensive than the C3 cycle.

Why are c4 and CAM photosynthesis more energetically expensive than c3 photosynthesis?

Adaptive Value: C4 plants photosynthesize faster than C3 plants under high light intensity and high temperatures. C4 plants do not have a photorespiration pathway, increasing photosynthetic efficiency. The C4 pathway is more expensive energetically than normal photosynthesis, but not as expensive as photorespiration.

Why is Photorespiration bad for plants?

Thus, photorespiration is a wasteful process because it prevents plants from using their ATP and NADPH to synthesize carbohydrates. RuBISCO, the enzyme which fixes carbon dioxide during the Calvin cycle, is also responsible for oxygen fixation during photorespiration.

Does Photorespiration occur in c4 plants?

Photorespiration occurs due to the oxygenase activity of RuBisCO. When the concentration of O2 is high, RuBisCO binds to oxygen and carries out photorespiration. C4 plants have a mechanism of maintaining high CO2 concentration at the enzyme site, thus photorespiration does not occur.

How do c4 plants deal with the problem of Photorespiration?

C4 plants largely bypass photorespiration by using an extension of the Calvin-Benson cycle to pump only CO2, and not oxygen, into the bundle sheath cells where the RUBISCO reaction occurs. C4 plants can maintain a high, local concentration of CO2 for RUBISCO activity without raising cellular oxygen levels.

Why is co2 compensation point low in c4 plants?


In C4 plants, the CO2 compensation point is zero or nearly zero, reflecting their very low levels of photorespiration. The CO2, absorbed by C4 leaves is fixed into organic acids, which thus maintain high levels of CO2. The mesophyll of C3 plants has no such mechanism of fixing CO2.

Why would it be beneficial to engineer a c3 plant using c4 genes?

We found C4 plants have less dense topology, higher robustness, better modularity, and higher CO2 and radiation use efficiency, which provide important basis for engineering C4 photosynthesis into C3 plants.

How do c3 plants avoid Photorespiration?

C3 carbon fixing plants are adapted to environments where they are able to keep their stomata open long enough during the day so natural circulation of gases keeps concentrations of CO2 and O2 in the leaf at proportions where photorespiration is less compromising and productivity is sufficient.