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Questions tagged [cellular-respiration]

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

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Where do the protons in the mitochondrial intermembrane space originally come from?

I'm currently reviewing this concept in cellular respiration. The book which I'm using is Reece, Minorsky, Campbell's Biology and while it does a good job at explaining the process involved in the ...
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Electron Transport Chain Proton Pumping into the Intermembrane Space

In regards to the electron transport chain, I know that complex I pumps 4 H+, complex III pumps 4 H+, and complex IV pumps 2 H+, but where do these numbers come from? If someone could explain this, ...
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Why is ATP synthase sometimes referred to as ATPase?

Quite a few times I have seen the term ‘ATPase’ used for what I would consider ATP synthase. For example, my text has: “The phosphorylation of ADP to ATP is also catalysed by the enzyme ATPase.” I ...
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Why is ATP used as a source of energy rather than glucose?

I'm struggling to pinpoint a misconception, but I don't think I understand why ATP is used as an energy molecule instead of glucose. I understand that glucose is respired, oxidised or combusted and ...
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In electron transport system the final acceptor of proton is?

My lecture notes say that the answer to this is inorganic phosphate (iP)..and the question is about proton not electron so the answer can't be oxygen. But I don't understand how is the answer iP
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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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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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How can the leakage of mitochondrial protons generate heat?

I read the following about thermogenin: "When thermogenin is inserted into the inner mitochondrial membrane, it accentuates mitochondrial proton leak and dissipates the proton motive force. ...
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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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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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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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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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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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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 ...
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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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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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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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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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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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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 ...
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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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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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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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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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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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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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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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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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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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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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Do seeds use cellular respiration when they are germinating?

Do seeds use cellular respiration when they are germinating?
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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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 ...