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The process in which energy is liberated from organic molecules producing ATP.

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Why doesn’t ethanol produced in respiration kill obligate anaerobes?

I have tried searching for some sort of mechanism whereby these bacteria either pump ethanol out or somehow convert it into a less toxic molecule that won’t denature their proteins but I haven’t been ...
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5answers
6k views

Why isn't Fluorine, or Neon, the final electron acceptor in cellular respiration?

I'm a Chemistry student learning about periodic trends. I know that in (many organisms') cellular respiration, oxygen serves as the final electron acceptor due to its high electronegativity. However, ...
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1answer
30 views
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0answers
16 views

Are potential calories/ATP lost from fat when converted to ketones?

When insulin levels are low, the liver begins to oxidize fat. The liver oxidizes fat by an incomplete process that yields ketone bodies. The incomplete oxidation of fatty acids by the liver yields ...
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2answers
57 views

how can mitochondrial proton leak make heat?

I read something about thermogenin. It said "When thermogenin is inserted into the inner mitochondrial membrane, it accentuates mitochondrial proton leak and dissipates the proton motive ...
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2answers
109 views

ATP production via aerobic respiration

Just started learning about aerobic respiration today, specifically Glycolysis. We were told that aerobic respiration produces 38 ATP, while anaerobic respiration produces only 2. However, we're ...
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0answers
33 views

Low energy in phosphate bonds in ADP molecule

I know that a phosphate bond breaks in an ATP molecule to release a lot of energy which results in an ADP molecule. Why does the phosphate bond in ADP molecule not break to release an equal amount of ...
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1answer
99 views

Why are there no multicellular prokaryotes [closed]

Why don't complex multicellular prokaryotes exits and also what made eukaryotes to become multicellular ?
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56 views

The effect of sugar on rate of yeast Respiration

In my experiment, I am investigating the effect of different types of sugar on the rate of respiration of immobilized yeast (yeast trapped in calcium alginate balls). I am looking at glucose, fructose,...
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1answer
35 views

What happens to the ATP after it stores energy?

The title says it all. After the procceses of cellular respiration happen, the energy is used in different activities that use it, but which are them, more specifically?
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1answer
100 views

Pyruvate oxidation - where did the hydrogen come from?

As shown in the diagram above, NAD+ is reduced and becomes NADH by gaining two electrons Now, where did the hydrogen come from? In the diagram, pyruvate has 3 hydrogen, but it still has 3 hydrogen ...
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0answers
25 views

How does a grape use tartaric and malic acid?

So I have conducted an experiment where different wines are tested from different regions with varying climates. It was seen by the results that the highest temperature had the lowest concentration of ...
1
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0answers
40 views

fermentation in soil bacteria

I am doing a project on microbial fuel cell. For the purpose of the efficiency of the question, MFCs can be summarized to: Devices that use anaerobic bacteria as the catalysts to oxidize organic ...
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0answers
105 views

Effects of Free Electrons In a Cell?

I am very new to biology, currently just a student. Recently I learned of the electron transport chain used in cellular respiration. This got me thinking. At the end of the chain, the electrons are ...
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1answer
126 views

As electrons are moving through the ETC, how is ATP produced for the active transport to even happen?

A lot of websites aren't being specific and they are just saying that when electrons move from a high to low energy state during the ETC, "energy" is being released and that energy is used to pump (...
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0answers
14 views

What physiological factors might affect the metabolism of an insect with a respiratory system like crickets and cockroaches?

I am trying to think of ideas of physiological aspects of insects specifically like crickets and cockroaches that can be altered in such a way as to increase their metabolic rates. So far all I have ...
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2answers
257 views

Intermediate of Krebs cycle that can form Chlorophyll?

This was a question in a test in my school today. Q) Which intermediate of Krebs cycle further can form chlorophyll? A) Oxaloacetic acid B) Citric acid C) Succinyl CoA D) Fumarate Given answer was ...
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1answer
154 views

Negative Oxygen Consumption Rate

Oxygen consumption rate (OCR) is defined as the rate at which cells consume oxygen. I reason that for cells not capable of photosynthesis, OCR is strictly non-negative. That was until I read this ...
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1answer
140 views

Why do zoologists classify sponges as animals rather than plants?

Sponges are fixed, do not move settle at one place, do not have a reproductive apparatus, respiratory apparatus, or organs, and live in marine environments. Why then zoologists consider that sponges ...
4
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1answer
112 views

How is Coenzyme A Transported to the Matrix?

So, I've been researching cellular respiration on my own, and trying to keep track of most of the major processes. However, I do have one question left: I can't seem to find any sort of information ...
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1answer
60 views

Viability of argon-oxygen atmosphere

Can humans breathe an Argon-Oxygen atmosphere, where Argon substitutes the inert Nitrogen gas which currently populates our atmosphere? I didn't quite know which forum to stick this one in; I put it ...
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4answers
666 views

Stomata during night (respiration)

How does carbon dioxide from respiration diffuse out of the leaf during the night? Do stomata close completely during night?
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0answers
188 views

Entropy increase or decrease in an reaction

My question is how would you tell if the product of an reaction has more or less entropy than the reactants? For example, in glycolysis, when glyceraldehyde-3-phosphate becomes 1-3 ...
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0answers
19 views

Can Phosphogycolate buildup in a plant kill it?

I'm trying to think of some things for the science fair, for part of my experiment I need to know if Phosphogycolate build up in a plant can kill it. Also, are there any chemicals that may disrupt the ...
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0answers
365 views

Is oxygen a respiratory substrate

I know that carbohydrates such as glucose are respiratory substrates for cellular respiration, but in this process, oxygen is also used to produce ATP so is it also a respiratory substrate?
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2answers
829 views

Pyruvate as a final electron acceptor in the electron transport chain

During anaerobic respiration, why are electrons carried by NADH not transferred to the electron transport chain (ETC)? What happens is that lactate dehydrogenase reduces pyruvate to lactate, while ...
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2answers
436 views

Role of ATP and AMP in functioning of Phosphofructokinase

I know that when ATP is more then it inhibits PFK and hence regulate the number of ATP. But how does PFK reactivates itself? Is it due to removal of ATP from allosteric site that just reconfigures the ...
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0answers
189 views

How long can algae survive with no air recycling (closed bottle)

In a small bottle nearly filled of Chlorella in water and grow medium, how long would it take for them to die (with or without light). Thanks in advance ;)
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1answer
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Why is carbon dioxide produced in alcohol fermentation but not in lactic acid fermentation?

From my understanding, alcohol fermentation takes place in yeast and lactate production takes place in humans. These two pathways take place only when there is insufficient oxygen, because the other ...
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1answer
288 views

Do seeds use cellular respiration when they are germinating?

Do seeds use cellular respiration when they are germinating?
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2answers
3k views

How many molecules NADH are produced in the Krebs Cycle?

I don't know which source i'm going to follow. Some say its 3 molecules NADH per cycle → 2 cycles × (3 NADH) = 6 NADH Some say its 4 molecules NADH per cycle instead?
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1answer
53 views

Is it possible to consume O2 via a pill form to inhibit the need to breathe?

Just wondering if it would be theoretically possible to consume oxygen via O2 pills, in the effort of being able to hold one's breath without limit. Totally just curious.
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2answers
497 views

Facultative anaerobic organism

While I was studying Cellular Respiration: Harvesting Chemical Energy, I found this question: An organism is discovered that consumes a considerable amount of sugar, yet does not gain much weight ...
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0answers
302 views

In what reaction of mitochondrial respiration is hydrogen peroxide an anomalous product?

I understand that hydrogen peroxide is produced in an anomalous manner during mitochondrial respiration, which also produces other by-products or free radicals. Does anyone know the details of the ...
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0answers
73 views

In what circumstances is ATP the limiting factor in performance for unicellular organisms?

I am interested in how enhanced energy levels in cells can contribute to elevated performance levels. Perhaps there have been experiments where unicellular organisms, enriched with ATP, were able to ...
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2answers
3k views

How much oxygen does a plant use up at night?

Given the fact that plants cannot do photosynthesis at night but need respiration for their energy needs, they use up oxygen and generate carbon dioxide. But how much is this? If I fill a room with ...
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1answer
382 views

Can a pyruvate reaction to acetyl coA be called as acetylation in any way? [closed]

Can the oxidation of pyruvate to acetyl coa be called as acetylation in some ways? Please include credible sources in the answer.
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1answer
397 views

What is the fate of NADH produced in the liver during oxidation of lactic acid?

NADH (‘reduced NAD’) is produced during the oxidation of blood lactate in the liver. Glycolysis requires NAD+ (‘oxidised NAD’), whereas gluconeogensis requires NADH. However the NADH is apparently not ...
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0answers
154 views

Why does lactate build up prevent a further increase in the speed of an athlete?

This question was triggered by an exam question that I was doing on the following paper (Q2 part (b)(i)): http://qualifications.pearson.com/content/dam/pdf/A%20Level/Biology/2013/Exam%20materials/...
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2answers
535 views

Do acetic acid bacteria use the electron transport chain when converting ethanol to acetic acid?

Do acetic bacteria use the electron transport chain when converting ethanol to acetic acid? And is wikipedia inconsistent here in its definition of fermentation. It says fermentation Fermentation ...
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2answers
345 views

Violation of the law of energy conservation between photosynthesis and respiration?

For the production of one glucose molecule in the Calvin cycle a plant uses 18 molecules ATP, but when the same glucose molecule is oxidised — first in the cytoplasm and then in the mitochondrion — it ...
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1answer
1k views

Why does ATP contain ribose rather than deoxyribose?

I read in a textbook that ATP is made from ribose and not deoxyribose. Originally, I thought that the pentose sugar didn’t have functional importance. Is there a functional reason why the ATP used ...
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1answer
387 views

Cellular respiration — How is the water expelled?

The equation of cellular respiration is as follows: 6 O2 (g) + C6H12O6 (aq) $\rightarrow$ 6 CO2 (aq) + 6 H2O (aq) + ATP How is the water produced expelled from the body (of course, after some ...
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1answer
57 views

Do sulfate reducing bacteria ingest their sulfate as solid, or as dissolved in water?

Do sulfate reducing bacteria ingest their sulfate as solid, or liquid or gas? I understand that almost all forms of sulfate are solid.. and sulfate can be dissolved in water(thus no longer solid, but ...
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3answers
5k views

Is glycolysis the beginning part of fermentation, or does fermentation follow glycolysis?

Is glycolysis the beginning part of fermentation, or does fermentation follow glycolysis? I see conflicting information from different sources https://honchemistry.wikispaces.com/Lactic+Acid+and+...
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0answers
543 views

How lymphocytes in lymphatic system get oxygen?

We know that the gas-transporting protein hemoglobin is absent from the lymphatic system. So, how does gas transportation takes place in lymphatic system? Is mere diffusion from surrounding blood ...
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0answers
20 views

Cytochrome Oxidase activity in neuronal cells

The abstract of this article says "...the entire neuron is often not metabolically homogeneous; most of the oxidative activity is usually found in dendrites." Why would the activity of cytochrome ...
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1answer
3k views

Why do bacteria produce H₂O₂?

I recently read up that people with NADPH oxidase deficiency (Chronic granulomatous disease CGD) have a tendency to be infected by Catalase positive organisms. NADPH oxidase helps produce the $H_2O_2$ ...
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0answers
42 views

why on hydrolysis ATP bond releases energy? [closed]

While studying respiration all i came across was that ultimately all that cell does is for the energy currency the ATP and some useful intermediates used in the cell building but i could not figure ...
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2answers
4k views

How is NAD+ used in lactic acid fermentation after it is oxidized from NADH?

I am confused with the whole process of glycolysis and the fate of the products of this reaction. So, I understand that anaerobic glycolysis results in 2 pyruvate + 2 NADH and 2 net ATP. Is the whole ...