stupid chemistry question

[timrandlerv10]

well, the chemistry isnt stupid, the question is.

here's a clip from an article about drinking water:

Phosphates â€" the main cleaning agent in many detergents and household cleaners â€" break down grease and remove stains. However, the chemicals are difficult to remove in wastewater treatment plants and often wind up in rivers and lakes, where they promote the growth of algae. And algae gobble up oxygen in the water that fish need to survive.



the part that confuses me is where algae consumes oxygen instead of c02...

help?

ty,

tim

 

[lorawalters13]

If I'm not mistaken, I believe that algae uses oxygen in the dark when photosynthesis is not possible. It might be the Krebs cycle??...sorry, I guess I've been out of school for too long

 

[Tomoko Schum]

Yep, lorawalters13 is correct. Algae produces CO2 and water through Krebs (citric acid) cycle. What Tim is thinking about is Calvin cycle where O2 and glycose is produced.

Two more things to study for you, Tim .

Tomoko

 

[timrandlerv10]

agh.

do you know where i can start?

 

[Tomoko Schum]

Try searching on web. Wikipedia is a good place to start, but it may give you a bit too much. Krebs cycle and Calvin cycle are closely interrelated. If you look up photosynthesis on web, there should be a number of sites that explain plainly how light respiration and dark respiration work, and you will see the references to both Krebs and Calvin cycles.

I just noticed that I misspelled glucose above.

Tomoko

 

[jrthomas40]

unless i just i was just a bad teacher...there is no krebs cycle in photosynthesis...only cellular respirartion and glycolysis use the krebs cycle...there are bacteria that have a reverse krebs

http://search.live.com/images/resul...com/images/news2/Photosynthesis-Denuded-2.jpg


cellular respiration and krebs cycle have to do with the production and break down of a citric acid called pyruvate

the light reactions in photosynthesis are photolysis and the transfer of adp to calvin cycle to produce ATP...so in other words the calvin cycle is dependent on the photolysis and transfer of adp....one can not last long with out the other...hence why plants die when they dont get enough sunlight...i have a quick powerpoint i had for my students if anyone is interested

 

[Tomoko Schum]

Krebs cycle does not occur in photosynthesis. Calvin cycle is the one related to photosynthesis. Modified citric acid cycle takes place in dark respiration. In plants the citric acid cycle is modified to a form called the glyoxylate cycle. Plant respiration encompasses several pathways, including glycolysis, the Krebs cycle, and oxidative electron transport. Pyruvate is produced in a fermentation process in plant's cytoplasm under an anaerobic condition. Once pyruvate has been produced, it moves along a different chemical patheway and produces ATP and ethanol, while in animals, pyruvate moves from the cytoplasm through the outer mitochondrial membrane and enters the Krebs cycle chemistry.

Tomoko