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5

You haven't directed us to any evidence for your assertion, so it is difficult to evaluate. I'm not a plant physiologist, so I will argue from first principles: photosynthesis consumes CO2 and produces O2: 6CO2 +6H2O -> C6H12O6 + 6O2 respiration consumes O2 and produces CO2: C6H12O6 + 6O2 -> 6CO2 +6H2O Plants do both of these things at the same ...


5

There are many different kinds of plants that have independently evolved this sort of variegation (non-green areas) in the leaves. However, the mechanisms by which they effect this vary between species. Some have little or no chlorophyll in the non-green areas, but many others have changed the architecture of their leaf cell layers in the non-green areas, ...


5

Disclaimer: photosynthesis is not my field of expertise. I assume you are asking about the amount of light needed for photosynthesis to take place, not the light intensity needed to sustain the plant? Since photosynthesis is an interaction between chlorophyll and single photons I would assume that photosynthetic reactions could take place with just single ...


4

According to this news article, in a NASA experiment one man survived for 15 days in a sealed chamber containing 30,000 small wheat plants. If you read the article you will find that this did not produce a completely balanced system - some excess oxygen had to be removed, and some extra CO2 had to be pumped in.


4

Your question conflates two separable events, a redox process and an acid-base dissociation. The interconversion between disulfides and free sulfhydryls is a redox reaction, governed by the redox potential of the surroundings. The importance of redox potential to the -S-S- <> -SH equilibrium is illustrated by the difference between the cytosol and the ...


3

I work on photosynthesis in algae, blue-green algae and anoxygenic photosynthetic bacteria. All would more or less be able to live on Mars in a blow up tent equipped with a simple blow compressor (like some tennis courts in cold climates). This could be used to raise the air pressure up enough (say 100 millibars) for water to exist in liquid form over a ...


2

Some wires crossed here. Most algae are C3, in other words they use the Calvin cycle to fix CO2. Another way of saying it is that RUBISCO (Ribulose bisphosphate carboxylase) is dorectly responsible for CO2 fixation. There is some evidence (disputed) that some diatoms use a form of the C4 pathway in which CO2 is initially fixed as a 4-carbon compound ...


2

Good question! The way that the carbon budget stays balanced was a bit of a mystery until recently. The amount of carbon in the atmosphere (and the rate at which it was increasing) was lower than models suggested that it should be, given rates of photosynthesis, respiration, and other carbon releasing processes. Somewhere, there was a "missing carbon sink" ...


2

The electrones which are generated from splitting water are later used to split CO2. The general formula is: The Photosystem II does the first part of the reaction by splitting up water and transferring electrons to plastoquinone and also by generating H+ ions. Water gets oxidized (spends electrons) in this reaction, CO2 in the end is reduced (receives ...


2

The wikipedia page on photosynthetic efficiency has some useful insight here: Photosynthesis increases linearly with light intensity at low intensity, but at higher intensity this is no longer the case. Above about 10,000 lux or ~100 watts/square meter the rate no longer increases. Thus, most plants can only utilize ~10% of full mid-day sunlight ...


1

Your task is to determine how light intensity and wavelength affect ATP production. Therefore, we know for sure that your dependent variable (or response variable) should be ATP production. It is customary to depict the response variable on the vertical axis (Y-axis), so let's trying doing this. Now we need to sort the other two variables. I suggest that ...


1

It turns out that the so-called light independent reactions are not light-independent at all: there are several regulatory mechanisms in place to prevent the turning of the Calvin Cycle when there is no light energy available to produce ATP/NADPH. The hypothetical situation you described in your question demonstrates the necessity of such regulation. The ...


1

First a clarification: the mobile units are no so "mobile". Due to (1) the high protein:lipid ratio of the thylakoid membrane and (2) the packing of protein complexes, the rapid diffusion of components along the membrane is hindered. It has been proposed the existence of small local PQ diffusion microdomains, based upon the percolation theory: From the ...


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http://link.springer.com/article/10.1007%2FBF00180642 study on the O2 production rate of one of the fastest growing species of cyanobacteria. The theory is not just someone's idea, its a conclusion made from trends which were discovered during the course of conducting countless experiments.


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I was all set to answer anothervquestion which has now been marked as a duplicate of this one. My answer adds new information relevant to the accepted answer here, so I have decided to post it here.. One longstanding candidate for something approaching this idea is the green sea slug Elysia chlorotica which uses chloroplasts derived from the alga Vaucheria ...



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