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

PHYLUM ANNELIDA, GERENAL CHARACTERICS OF PHYLUM ANNELIDA

GERENAL CHARACTERICS OF PHYLUM ANNELIDA

Undergraduate thesis title, Hi,I am a graduating student from my course BS ...

Hi,I am a graduating student from my course BS in Biology major in Zoology. I was wondering if you guys have any great idea of a good thesis title?

How old is the earth, How old is the earth? It is believed that the ear...

How old is the earth? It is believed that the earth is about 4.5 billion years old.

Explain the secretary phase - menstrual cycle, Explain the Secretary Phase ...

Explain the Secretary Phase - Menstrual Cycle After ovulation, the lining of ovarian follicle is stimulated by LH to develop corpus luteum which produces progesterone. The endo

Why is the aids treatment often done with a drug cocktail, Why is the AIDS ...

Why is the AIDS treatment often done with a drug cocktail? The treatment of acquired immune deficiency syndrome is often done with one or more anti-retroviral drugs of dissimil

Bacterial diseases-pigs, Pigs This is a sub-acute or chronic infection ...

Pigs This is a sub-acute or chronic infection manifested by abortion, sterility, high piglet mortality and orchitis in pigs. Br. suis causes brucellosis among pigs. It is morph

How to produce a similar sickling effect, Which of the following amino acid...

Which of the following amino acids would you expect to produce a similar sickling effect if placed at position 6? Select all that apply. 1. Arginine 2. Leucine 3. Lysine

What is available soil nutrient, Availability of nutrients in soils  Th...

Availability of nutrients in soils  The productivity of a crop depends largely on the nutrients discussed in the previous section. It is important to find out methods which wil

Define factor contribute to malabsorption - radiation damage, Define Factor...

Define Factors Contribute to the Malabsorption - Radiation Damage? Malabsorption of water, fats, bile salts, carbohydrates, calcium, magnesium, iron and vitamin B 12 occur dur

Why conserve wild life ?, WHY CONSERVE WILD LIFE ? 1 .       ECONOMIC...

WHY CONSERVE WILD LIFE ? 1 .       ECONOMIC IMPORTANCE OF WILD LIFE - (i) Plants - (ii) Animals - (iii) Micro organisms - 2 .       ECOLOGICAL BALANCE -

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