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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 ...


5

Chlorophyll can use a quite broad range of light for photosynthesis, the only range where it is not working is approximately between 500 and 620nm. See this adsorption spectrum of chlorophyll (from the Wikipedia article on Chlorophyll): The lack of chlorophyll to absorb light between 500 and 620nm (roughly) results in the green color of leafs, because ...


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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.


3

You are missing some knowledge here for sure, photosynthesis is a little complicated at A level, so I will describe it in brief. During photosynthesis electrons and protons (A hydrogen atom without the nucleus) are required for a process called the electron transport chain and proton motive force. This happens during the light dependent stage of ...


2

This question is related to the question: Why are some things transparent and others opaque? Being able to see something requires that it is opaque and that sufficient light illuminates it. UV and shorter wavelengths are not as prevalent as visible light on earth. The world would appear too dark to see if we used UV and shorter wavelengths. This is ...


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 ...


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" ...


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Phosphorus Your suggestion that if we are meeting our calorific requirement we will be getting enough is true for phosphorus. Most foods contain lots of phosphorus. The maximum dietary requirement occurs during adolescent growth, estimated at 1250 mg per day. Assuming a calorie intake of 2500 kcal we can calculate a 2500 kcal equivalent phosphorus content ...


2

I would hardly ever say never where biology is concerned. In this case that utilizing red rather than blue light for a plant would require many of the basic assumptions of photosynthesis in terrestrial plants to be revised, but since we're talking about another planet, that might not really be an issue. If we are asking only about how we could change our ...


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I am not sure about the source of ATP but I can tell you something about NADPH. The conversion of malate to pyruvate and CO2 by malic enzyme is carried out in the bundle sheath cell. This process produces NADPH.


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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 ...


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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 ...


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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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A rule of thumb in optics is that light interacts with materials that have features with dimensions similar to the wavelength of light. For example, radio waves with large wavelengths interact with large objects like airplanes ,as in the case of radars, and really small wavelengths (x-rays & gamma rays) interact with really small objects like nuclei of ...



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