Explain alternate photosynthetic pathways, Biology

Assignment Help:

Explain Alternate Photosynthetic Pathways?

An alternate photosynthetic pathway is the C4 pathway, where plants incorporate carbon into four-carbon compounds instead of 3PG. This pathway was found when plants were exposed to 14CO2, a radioactive substance used to trace the steps in biochemical reactions.

In these plants, the CO2 acceptor is phosphoenolpyruvate, or PEP, for short. The four-carbon compounds formed by the C4 pathway reactions are taken up by another type of cell, that releases CO2. The CO2 is taken up by RuBP and used in the Calvin cycle to form sugars used to synthesize and store starches. The reaction catalyzed by the enzyme PEP carboxylase can proceed in very low concentrations of CO2. This represents an adaptation to dry environments, where plants conserve water by keeping the stomata, openings in the leaves where gas exchange occurs, closed as much as possible.

The CAM, or crassulacean acid metabolism, pathway, occurs in cacti and other desert plants. It is similar to the C4 pathway, except that the PEP carboxylase reaction occurs at night and the Calvin cycle predominates in the daytime. During the daytime, the stomata close to preserve water, and the plant uses CO2 trapped in the four-carbon compounds for its metabolism.

 

 


Related Discussions:- Explain alternate photosynthetic pathways

Modification of carbohydrate intake for specific disorder, Define Modificat...

Define Modification of Carbohydrate Intake for Specific Disorder? In our daily diet almost 60-7096' of energy is contributed by carbohydrates. Majority of them are comprised of

Representatives of the echinoderm phylum, Q. What are some representatives ...

Q. What are some representatives of the echinoderm phylum? Starfishes, sea urchins, sea cucumbers (holothurians) and brittle stars are examples of echinoderms.

Explain the biography of pedanius dioscorides, Explain the Biography of Ped...

Explain the Biography of Pedanius Dioscorides? Pedanius Dioscorides, a Cicilian Greek, who lived in the first century A.D. was the most important botanist after Theophrastus. H

Explain hypertensive response, Q. Explain Hypertensive Response? Hypert...

Q. Explain Hypertensive Response? Hypertension at rest has long been known to be a risk factor for the development of coronary artery disease (CAD). Significant elevation of B

Determine about the national adult reading test, Determine about the Nation...

Determine about the National Adult Reading Test The National Adult Reading Test (NART; Nelson, 1982) allows the researcher to obtain an estimate of an individual's IQ prior to

How can nutrients are classified, Q. According to their functions how can n...

Q. According to their functions how can nutrients are classified? One possible and utile functional classification for nutrients is the one that separates them into energetic,

Why is ph regulation important for living beings, Why is pH regulation impo...

Why is pH regulation important for living beings? How do mineral salts participate in this regulation? The potential of hydrogen (pH) is a measure of the amount of hydrogen ion

What is the gross primary production of an ecosystem, What is the gross pri...

What is the gross primary production of an ecosystem? How does GPP relate to photosynthesis? Gross primary production of an ecosystem, or GPP, is the amount of organic material

Why immune mechanism of body of a patient gets suppressed, Name the disorde...

Name the disorder in which the immune mechanism of the body of a patient gets suppressed. Which pathogen is responsible for it? Give any two reasons of its transmission.

Risk factors for gdm, Q. Risk Factors for GDM? If any of the following ...

Q. Risk Factors for GDM? If any of the following risk factors are present in a woman, she may develop GDM: 1) Presence of obesity. 2) If any family members (parents, brot

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd