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

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Respiration of an animal cell media

I want to do respiration process of an animal cell media in laboratory environment. I don't entirely sure how to supply it with Oxygen to the process because it is a gas, but not a liquid.
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23 views

Typical cellular respiration lab with a respirometer — why is potassium hydroxide (KOH) necessary?

For context, if you are unsure what this question is in reference to, feel free to take a look at this video by Bozeman science and go forward to about the 2:00 mark. In a typical cellular respiration ...
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44 views

Do all prokaryotes have ATP synthases and an electron transport chain?

I was looking this up and I'm wondering if so far I'm correct about the following: For the most part eukaryotes do aerobic respiration, which involves glycolysis, the Krebs cycle and oxidative ...
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49 views

Electron Transport Chain in Mitochondria [closed]

I was researching cellular respiration, and this is a rather confusing part. I need help understanding the purpose of Complex II and how the ATP Synthase generates the energy to turn ADP to ATP.
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45 views

Why don't protons diffuse out of the mitochondria during chemiosmosis?

If the outer membrane of the mitochondria is very permeable, how do mitochondria maintain a proton gradient by pumping protons into the intermembrane space? Wouldn't they just diffuse into the ...
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0answers
18 views

Potential homogeneity across cell membrane

During respiration, individual bacteria (and mitocondria) produce a relatively large potential difference (∼100 mV) between the inside and outside, using energy to pump $H^+$ out of the cell to the ...
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207 views

Why is ATP produced in photosynthesis used to synthesize glucose?

In photosynthesis ATP is produced in light-dependent reactions only to go to the Calvin cycle to be turned into glucose to make ATP during respiration: Why isn't this ATP just directly released ...
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1answer
30 views

How exactly do we get “energy” from food? [closed]

I am captivated by human biology and I'm currently trying to understand the body and its processes in a greater depth. Thank you so much for your time and consideration! :-D I'm sorry for the rambling ...
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15 views

Mechanism behind energy generation

I recently read about methanogens and methanotrophs. One converts CO2 to methane and vice versa respectively. I can't get exact mechanism for the methanotrophs and I know they can't be reversed ...
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407 views

How is respiration an unbalanced equation

The equation for respiration is C6H12O6+6O2→6CO2+6H2O+36ATP. The chemical formula for ATP is C10H16N5O13P3. How is this possible, since it violates the law of conservation of mass because it is ...
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Where is the line between Anaerobic and Aerobic?

I am well aware of traditional anaerobic respiration (lactic acid or alcohol produced - no Krebs cycle) and traditional aerobic respiration (O2 is used at the end of the Citric acid cycle). I am ...
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114 views

What's the point of glycolysis in fermentation?

In order to initiate glycolysis, 2 ATP are necessary. In the glycolytic process, you generate an additional 4 ATP, which results in a net gain of 2 ATP. If you don't undergo glycolysis, however, then ...
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188 views

Why is succinate dehydrogenase attached to the inner mitochondrial membrane?

Succinate dehydrogenase is attached to the inner mitochondrial membrane. All the other enzymes of the Krebs cycle are located within the matrix of mitochondria, though. In biological systems, there ...
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1answer
751 views

Why does NAD+ become reduced if it gains a hydrogen proton?

I've heard that $NAD^+$ gains a Hydrogen proton during glycolysis and the Krebs cycle and becomes reduced to $NADH$. However, isn't reduction when a molecule receives an electron? Maybe I've been ...
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44 views

In glycolysis, what is the source of the electron that makes NAD+ into NADH instead of NADH+? [closed]

I looked at the formula for the glycolysis reaction. The overall reaction seems balanced, however, I don't see anything on the left hand side of the equation that would provides the electron to ...
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0answers
21 views

How are muscle fibre size and oxygen consumption related?

Does anyone know of a paper which correlates the muscle fibre size to oxygen consumption in mammals? I am trying to find a correlation between muscle fibre type, size and (absolute and specific) ...
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1answer
62 views

Are there differences in energy of glucose isomers?

There are many isomers of glucose, including galactose and fructose. Do they have different chemical energy levels, and why? What makes galactose and fructose useful compared to glucose, and would ...
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174 views

ATP utilized in Glycolysis vs. Gluconeogenesis

In glycolysis, the conversion of glucose to pyruvate results in a net gain of 2 ATP molecules. In gluconeogenesis however, the conversion of pyruvate back to glucose requires 6 ATP molecules. Why ...
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1answer
77 views

What is the name of cellular respiration that Prokayotic cells use?

Eukaryotic cells use mitochondria using anaerobic or aerobic respiration. Prokayotic cells lack mitochondria but are bacteria. Mitochondria originated from bacteria and can be used in the same way. ...
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1answer
38 views

ATP yield of fermentation: study to cite?

Everywhere I find the ATP yields of respiratory and fermentative metabolism of glycolysis. While that of oxidative phosphorilation I could find in Stryer to cite one study where this was addressed ...
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3answers
122 views

What product of cellular respiration creates an acid when in solution with water?

What product of cellular respiration creates an acid when in solution with water? Topic question really, haven't been able to find a direct answer.
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25k views

How do prokaryotes perform cellular respiration without membrane-bound organelles?

In order to survive, prokaryotes such as bacteria need to produce energy from food such as glucose. In eukaryotic cells, respiration is performed by mitochondria, but prokaryotic cells do not have ...
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1answer
142 views

Why do we breath oxygen? [closed]

I like this contradiction. But seems like my Biology teacher doesn't. If oxygen oxidates us, why do we breath it? Why can't we evolve into a new kind of human being that breaths other component of ...
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1answer
160 views

Membrane Permeability to Pyruvate

Pyruvate seems to pass easily through the outer membrane of the mitochondrion but has difficulty entering the inner membrane (and gets in by H+ symport). I have two questions: (1) what property of ...
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5answers
11k views

Why don't we breathe nitrogen when it makes most of the air?

Why don't we breathe nitrogen while it makes most of the air? Why do we always tend to breathe oxygen, not hydrogen and nitrogen?
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9k views

What does the human body use oxygen for besides the final electron acceptor in the electron transport chain?

My biology teachers never explained why animals need to breathe oxygen, just that we organisms die if we don't get oxygen for too long. Maybe one of them happened to mention that its used to make ATP. ...
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208 views

If oxygen deficiency is bad even for a short while, why do people swim?

This may be trivia to many of you. Textbook says the oxygen deficiency, even for a short while can injure our cells. Then why do people go for sports like swimming? (where rhythmic breathing is ...
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Where does the 'C' in exhaled CO₂ mostly come from?

When a human being exhales CO₂, what is, by the numbers, the main source of carbon atoms exiting the body in this way? I mean what class of cells, or which tissues are the biggest on a pie chart of ...
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1k views

Cellular Respiration/Fermentation Problem Leading to Lack of Energy

A young animal has never had much energy. He is brought to a veterinarian for help and is sent to the animal hospital for some tests. There they discover his mitochondria can use only fatty acids and ...
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227 views

If higher levels of atmospheric oxygen can lead to larger animals, can it also lead to larger plants?

According to some information, in the ancient past (at least some) animals grew larger due to a higher levels of oxygen in the atmosphere. So for example there is this study regarding dragonflies. ...
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Why is the Krebs cycle considered a part of aerobic metabolism if molecular oxygen is not involved in any of the reactions in the cycle

Why is the Krebs cycle considered a part of aerobic metabolism if molecular oxygen is not involved in any of the reactions in the cycle? I originally thought that Krebs cycle was aerobic metabolism ...
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42 views

Need for two oxygen sensors in E. coli

E. coli has two oxygen sensors: FNR (fumarate-nitrate reductase) and ArcBA (Anoxic Redox Control, two component control systems). FNR directly senses the oxygen, while the interaction of ArcB with ...
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214 views

Fermentation to acetic acid

How much time is needed for the fermentation to acetic acid production cycle, and the conversion of apple vinegar in a sealed container incubated at 37 °C? Should be in the fully closed? What is ...
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79k 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 ...
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160 views

cellular respiration

What are the effects of addition of these chemicals to actively respiring cells ? Which of them would lead to INHIBITION of aerobic respiration ? Would cytochromes be actually taken up by cells ? ...
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775 views

What effect does ambient temperature have on the cardiovascular system?

I am sorry if this is not appropriate for this site, but I think it fits so I am asking it here: I went for a run yesterday, and it was about -8⁰C. I was wearing a couple pairs of shorts, a t-shirt ...
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606 views

Aerobic vs anaerobic respiration comparison

The following graphs compare glucose decomposition in yeasts (in anaerobic vs aerobic conditions respectively) My question is, why doesn't the first one look like a straight line as the second one ...
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2answers
448 views

Why can we breathe only oxygen?

Plants has the capacity to take in both CO2 and oxygen, that's during day CO2 and at night oxygen. Why don't humans have such a capability?
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1answer
3k views

Given ATP synthase's structure, how can 3.33 protons ultimately synthesize one and only one ATP?

I am familiar with the structure and function of ATP synthase, but one small detail doesn't seem to make sense. It also happens to be a detail that seems very hard to express. Depending on the ...
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1answer
791 views

Mitochondria - are they really separate organisms that once merged into eukaryotic cells?

Theoretically, mitochondria are said to be a separate organism that is concerned with its own life and its own processes. In fact, it even duplicates individually. I know a similar question is here ...
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Why is oxygen needed for the electron transfer phosphorylation?

I understand that oxygen is the acceptor of electrons and hydrogen ions during the electron transfer phosphorylation, the last step off the ATP-producing aerobic respiration. But why? Aren't there ...
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1answer
161 views

Source of hydrogen in reduction of oxygen in electron transport?

What's the source of hydrogen in the reduction of oxygen to water in metabolism? Is this implying that half the hydrogen comes from NADH and the other half from lone protons?
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1answer
87 views

Missing 4$H_2O$s (per glucose) in Cellular Respiration… Where can they be?

I having trouble understanding the equation of the cellular respiration. The thing that bothers me is the number of $H_2O$ molecules. Generally, cellular respiration is written thus : $C_6H_{12}O_6 + ...
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1answer
108 views

Diffusion of FAD+

Why is NAD+ free to diffuse within the mitochondrion whereas FAD+ is not ? What biochemical properties cause this difference ?
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1answer
2k views

How do the first and second law of thermodynamics adhere to breakdown of glucose?

I know the first law is energy can only be converted from one form to the other, therefore in the breakdown of glucose 40% potential energy is converted to ATP and 60% is converted to thermal and ...
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1answer
48 views

What are the molecular mechanisms that make the turtle brain more resistant to hypoxia?

I know that turtle brains, particularly those of individual species that hibernate and burrow are particularly resilient to hypoxia and any tissue damage secondary to a hypoxic event. What are the ...
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1answer
505 views

Breathing in and out

I was reading my textbook and it says that breathing involves inhaling and exhaling but it doesn't say whether they happen simultaneously or sequentially. Also is my overall understanding of ...
11
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1answer
2k views

Do fish break a water molecule to absorb oxygen?

How do fish separate oxygen from H20 & consume it? Do they break the water molecule and absorb the oxygen only?
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74 views

Critical pO2 threshold for cell division?

I'm a physicist asking questions on an aspect of cellular metabolism, so excuse my biological ignorance! Hypoxia is a frequent complication of certain tumour types, and has quite an implication for ...
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1answer
509 views

Confusion regarding photosynthesis and respiration in plants

During 24 hours there is a time in i.e. twilight when plants neither give oxygen nor carbon dioxide why is it so? This also suggests that neither of the two vital processes i.e. respiration or ...