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

Renewable energy sources, Capacity to do work is known as energy. It is ver...

Capacity to do work is known as energy. It is very important input for all our activities like cooking food, driving vehicle and running industries. The most important challenge th

Explain capillaries of the vascular system, Q. What are the capillaries of ...

Q. What are the capillaries of the vascular system? Capillaries are small blood vessels that perform exchange of substances between the tissues and blood the body Capillaries a

What is phosphorylation, What is phosphorylation? What are some biological ...

What is phosphorylation? What are some biological processes in which phosphorylation plays a critical role? Phosphorylation is the name given to processes of the addition of ph

Which are the structures that are part of the nervous system, Q. Which are ...

Q. Which are the structures that are part of the nervous system? The structures that form the nervous system can be divided into the peripheral nervous system (PNS) and the cen

Difference between the reptile heart and the amphibian heart, Q. What is th...

Q. What is the difference between the reptile heart and the amphibian heart? The reptiles have incomplete and double circulation three heart chambers two atria and one ventricl

Fertilisation, Explain how the uterus supports the development of a baby du...

Explain how the uterus supports the development of a baby during gestation

Acrylamide gel, Acrylamide gel  is a polymer gel used for electrophoresis o...

Acrylamide gel  is a polymer gel used for electrophoresis of DNA or protein to measure their sizes (in the daltons for proteins, or in base pairs for DNA). See "Gel electrophoresis

Haccp - what is validation, HACCP - What is Validation Validation   : ...

HACCP - What is Validation Validation   :  That element of verification focused on collecting and evaluating scientific and technical information to determine  if  the HACCP

Importance of fat synthesis and storage, Importance  of fat  synthesis  ...

Importance  of fat  synthesis  and storage : As  is clear from above  account, all  surplus nutrients, digested and  absorbed  from above the  immediate need of  body, are readily

How ph affect the initial rate of an enzyme, How does pH affect the initial...

How does pH affect the initial rate of an enzyme -catalyzed reaction?

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