The process in which light energy is harnessed to assemble organic compounds (esp. glucose) from inorganic carbon dioxide.
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0answers
34 views
Electron transport in granal stacks
See paper for distribution of PS-I and PS-II within grana
As explained in the above paper, the PS-I complex is primarily located within non-appressed thylakoid region and stroma lamella, while PS-II ...
4
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1answer
37 views
Photosynthesis regulation
I read about the regulation of Calvin cycle by thioredoxin which activates key enzymes essentially by converting disulphide linkages on inactive enzymes into sulfhydryls. Another regulatory mechanism ...
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1answer
52 views
What type of photosynthesis is performed by phytoplankton?
I am not a biologist, but I know there exist three variants of photosynthesis, namely C3, C4 and CAM.
I would like to know what type is used by the ocean's phytoplankton? It might also be that ...
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0answers
31 views
Cyanobacterial photosynthetic oxygen yield
I am somehow not convinced that biotic factors are solely responsible for creating 21% of atmosphere (around 40 million moles of oxygen).
There may be additional issues here. Since cyanobacteria ...
1
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1answer
36 views
What part of the cactus photosynthesizes?
In general, plants photosynthesize through their leaves and, to a much lesser extent, through their stems. Cacti, however, have no visible leaves, but instead spines. In what part of the cactus does ...
2
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1answer
38 views
Is Hypericum Perforatum (St. John's wort) a C3 or C4 plant?
I've been curious as to which photosynthetic cycle St. John's wort uses to synthesise glucose and more complex carbohydrates. I know it probably won't be the crassulacean acid metabolism (CAM) cycle ...
2
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1answer
47 views
How does this diagram illustrate carbon cycling in lakes?
Could someone please explain the following process to me:
This process refers to carbon cycling in lakes and is described in the context of $CO_2$ flux from lakes into the atmosphere. GPP is gross ...
4
votes
1answer
113 views
Do plant-animal cross races exist?
Plants and animals have the following distinct properties:
Plants live from solar energy by photosynthesis, they use solar energy to make sugar and oxygen out of carbon dioxide, which gives them ...
7
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2answers
125 views
Does Sansevieria trifasciata really absorb Carbon Dioxide at night?
There's a claim that Sansevieria trifasciata (Mother-in-law’s Tongue) generates oxygen from carbon dioxide during the night.
This seems surprising to me: that process requires energy; plants generate ...
2
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1answer
54 views
Photosynthesis - Light Intensity
Say I was conducting an experiment for photosynthesis. If I moved light closer to the plant, what effect would this have on the process of photosynthesis?
8
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2answers
222 views
What vegetation would thrive in the Martian atmosphere?
Most plants require carbon dioxide for their photosynthesis, which Mars has in overabundance.
Would atmosphere composition (let's ignore temperatures for the purpose of this question) of Mars allow ...
8
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1answer
163 views
Can Bioluminescence drive photosynthesis?
I'm trying to construct an anaerobic kitchen-waste digester at home.
The major output from the digester is methane - with a significant component of carbon dioxide. To scrub/reduce the CO2 I was ...
5
votes
1answer
189 views
Does the light color spectrum and frequency matter for photosynthesis?
Do plants grow differently when given sun light, wolfram lamp, fluorescent light, LED light, infrared, ultraviolet, x-ray, unfocused laser and stroboscope?
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2answers
968 views
Is there an evolutionary reason for the 5 electron transport complexes in plants and animals?
The electron transport chains of both the light reactions of photosynthesis (in plants) and oxidative phosphorylation (in animals) both contain 5 complexes including ATP synthase, as shown below.
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7
votes
2answers
74 views
Exactly which amino acids are phosphorylated in higher plants during state transitions?
I know it is usually stated as the threonine residue near the N-terminus of either light harvesting complex (lhc) b1 or lhcb2, but if this is somehow lost, say in a mutant, is the system flexible ...
5
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1answer
192 views
Photosynthetic Pigments vs. Chloroplasts
What is the difference between Photosynthetic Pigments and Chloroplasts? I know plants have both but Prokaryotes (Bacteria and Archeae) only have the former.
5
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1answer
193 views
Do all plants photosynthesize with equal efficiency?
Just what the title states.
Given identical, necessary and favourable conditions (Probably nutrients, humidity, and light but what I mean is all necessary requirements are fulfilled) - Is ...
4
votes
2answers
102 views
How high is the energy yield of photovoltaics compared to photosynthesis?
I'm not an expert in plant physiology. I was wondering if, per square centimeter, leaves are converting more or less energy than photovoltaic systems. Can this be estimated? How?
6
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1answer
172 views
Can I estimate leaf temperature from air temperature? What other information would be required?
Physiological measurements such as respiration rate and assimilation rate depend on temperature.
Most papers report tissue temperature (e.g. leaf temperature for leaf measurements), although some ...
17
votes
4answers
880 views
Do trees really get a large share of their mass from the carbon in the air?
I remember hearing that trees and other plants actually obtain a large amount of their mass from the carbon floating in the air, not the ground beneath them. Does the makeup of air actually contain ...
11
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1answer
72 views
Does a theory exist for the formation of thylakoid structure?
I'm interested in how the structure of the thylakoid forms into its characteristic highly rugose stacks of grana. What causes the thylakoid to invaginate and self-associate, albeit with what appear to ...
5
votes
1answer
219 views
Do immature fruits perform photosynthesis?
Most immature fruits are green: peppers, pine cones, plums, lots of them. I want to know if the green is from chlorophyll in the cells. Do the fruit cells perform photosynthesis? When you cover a ...
9
votes
1answer
473 views
What's the effect of oxygen deficit on plants?
As I know all cells require oxygen. So my question is how efficiently can plants operate in no-oxygen atmosphere? Do all plants produce enough oxygen for themselves? Can they consume their own oxygen ...
6
votes
1answer
161 views
How do white Caladiums perform enough photosynthesis to support their mass?
In some white caladiums, there is less than a square inch of green space spread over the whole leaf. How do these plants perform the photosynthesis necessary to support the large leaves, the roots, ...
7
votes
1answer
140 views
Compare and contrast “Rubisco activity” and “assimilation rate” (is there a difference, and if so, what is it)?
I am confused about the variable "RuBisCO activity". How is it measured, and is it any different from the net assimilation rate?
Based on some background reading (e.g. Kling, 2008; Lambers et al ...
11
votes
1answer
849 views
How does a plant grow before photosynthesis is possible?
During photosynthesis, a plant translates CO2, water and light into O2. I assume the carbon C is further used for the growing process. I wonder how the plant grows before the time where photosynthesis ...
7
votes
1answer
9k views
NADH vs. NADPH: Where is each one used and why that instead of the other?
I know NADH is used in cellular respiration and NADPH is used in photosynthesis. What difference does the phosphate group make that the same one isn't or can't be used for both? Is there a greater ...
12
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2answers
1k views
How will rising carbon dioxide levels in the troposphere affect photosynthetic producers?
Much discussion has been had about the affects of climate change on plantlife, but how will rising carbon dioxide concentrations affect the photosynthetic process itself? Since CO2 is a reagent in ...
37
votes
3answers
591 views
Is there a reason why human eyesight and plants make use of the same wavelength of light?
The accepted range for the wavelengths of light that the human eye can detect is roughly between 400nm and 700nm. Is it a co-incidence that these wavelengths are identical to those in the ...
30
votes
4answers
2k views
Why do plants have green leaves and not red?
I know plants are green due to chlorophyll.
Surely it would be more beneficial for plants to be red than green as by being green they reflect green light and do not absorb it even though green light ...
