The set of chemical reactions that happen in the cells of living organisms to sustain life.

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Should we induce fever to assist healing?

I am currently reading "The Fundamentals of Anatomy Physiology" 10th edition, and have found it an incredibly interesting book. I have just been reading about the lymphatic system, and the various ...
4
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1answer
204 views

What do trans-fats do when in human body?

Trans fats cause health problems, especially to the heart. https://en.wikipedia.org/wiki/Trans_fat#Health_risks My guess is that all effects happen because trans-fats are inherently toxic as the ...
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1answer
23 views

Mitochondria variability per tissue in humans?

I would like to know the distribution of mitochondrial content per tissue type in humans. I understand the simple metric that energetically active or energy requiring tissues will have more ...
2
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0answers
5 views

MTHFR recessive alleles and B-vitamins

I know that being heterozygous or homozygous recessive for the MTHFR gene prevents that person from being able to process and use folate and B-12. It causes an unhealthy level of homocysteine to ...
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3answers
65 views

What is the relationship between protein-protein interaction networks and metabolic networks? [closed]

I am trying to find out how these networks can be linked together. I know that Protein-protein interaction networks and metabolic networks both fall under the Intra-cellular type of biological ...
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0answers
50 views

Why do plants produce so much more sugar than they use?

I recently asked the question, "Do plants need O2 to consume energy they've stored via sugar?" to which @canadianer responded, "Yes, plants require oxygen to generate ATP from sugar. However, they ...
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23 views

Do plants need O₂ to consume energy they've stored via sugar?

This question came up as I work my way through the answers to another question I just asked. My understanding is that plant photosynthesis looks something like this (though with lots more going on ...
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2answers
50 views

How does it make thermodynamic sense for photosynthesizers to turn CO₂ into O₂?

My understanding is that animal metabolism consists of exothermic reactions like $$\ce{C6H12O6 + 6 O2 ->6 CO2 + 6 H2O + energy}$$ This makes thermodynamic sense to me. Animals need an exothermic ...
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25 views

Metabolism of different saccharides

Learning about carbohydrates, I wonder what the differences there are in terms of metabolism, and overall health between the different types of saccharides. In other words, does the body use ...
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67 views

Why is iodine used for metabolic hormones?

Iodine and related biological iodine-carrying hormones are phylogenetically very old, at least according to Wikipedia. Humans use iodine as a metabolic indicator, as do axolotls and apparently most ...
4
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1answer
29 views

How to measure heat loss in Tardigrades

I want to measure metabolism in tardigrades (a jar of 30 tardigrades). I know that an easy way to measure metabolism is heat loss; I can just measure the temperature of the water before and after a ...
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0answers
15 views

Which biosynthetic pathways take place in the plastid and were are they located?

I know that the isoprenoid, jasmonate, glucosinolate, fatty acids, chlorophyll, starch, and aromatic amino acid syntheses are located in the plastid. But I don't know if they are located in the ...
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34 views

Does the metabolic rate determine how fast the telomeres shorten?

In many papers one can read that telomeres may play an important role in longevity. According to Calado et al.1 the telomeres of mice are much longer than the telomeres of humans. However, mice have ...
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1answer
49 views

How to measure metabolic rates of microscopically small animals?

I want to measure metabolism rates in Tardigrades Metabolic rates will be assessed immediately following their exit from cryptobiosis (an animal dormant state). I know that oxygen levels is the ...
2
votes
1answer
48 views

Energy metabolism in Cancer cells

The TCA cycle intermediate Isocitrate dehydrogenase commonly undergoes point mutations in cancers. This allows IDH to reduce a-Ketogluterate to 2Hydoxygluterate, causing a reduction in pVHLs ability ...
6
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1answer
57 views

How does the body “know” how to metabolize foreign substances

As a freshman biochemistry major, I find myself befuddled by our body's ability to perform complex chemical reactions to break down foreign substances. I can see how we would evolve explicit pathways ...
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2answers
603 views

What causes muscles to generate heat on contraction?

I'm curious what the exact cause is of dramatic heat generation that comes along with muscle activity. Can anybody explain this in understandable language?
4
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1answer
35 views

What is the biggest facultative anaerobic metazoan known to science?

Related: What's the biggest obligate anaerobic organism discovered till now? I had always assumed that the Riftia tube worms were obligately anaerobic since they lived next to anoxic volcanic ...
3
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0answers
41 views

Statistical method for characterizing the relationship between body mass and metabolic rate

There is a dataset that contains body mass ($x$) and metabolic rate ($y$) from many different organisms. It is common to fit the data to the model of the form $y=ax^b$ and estimate the parameters $a$ ...
7
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1answer
302 views

Does THC excretion increase if urine volume increases?

In regards to the body metabolizing and excreting THC: if urination is increased as a result of drinking lots of fluids, does that mean that more THC is leaving the body? To rephrase the question, is ...
2
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2answers
57 views

How does the cell regulate different metabolic pathways?

I heard somewhere that cells use different nucleosides bound to triphosphates e.g. ATP, GTP, CTP and other modified compounds: NADH, NADPH to distinguish between different metabolic pathways and so ...
4
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1answer
29 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 ...
3
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2answers
62 views

Tracking of oxygen molecules in glucose oxidation

For this reaction, found in typical biochemistry textbook: $C_6H_{12}O_6 + 6O_2 \to 6CO_2 + 6H_2O$ I am interested in where do the oxygen atoms of $6O_2$ go. I think they go to $6H_2O$, but this is ...
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904 views

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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0answers
12 views

How reactive are reduced antioxidant molecules?

When antioxidant molecules stabilize free radicals, they themselves become unstable and reactive but to a lesser degree. How reactive are these reduced antioxidant molecules? And what substance ...
3
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1answer
56 views

Burning fat transferred from one part of the body to another

While doing some research on cosmetic surgery, I discovered that there are several ways of doing breast enhancements, one of which was using body fat. While I haven't researched this method, I assume ...
3
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1answer
39 views

Can chitosan affect the absorption of unsaturated fatty acid?

I know chitosan will decrease the absorption of fat. However unsaturated fatty acid, such as DHA, is beneficial. Does chitosan effect the absorption of unsaturated fatty acid?
5
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1answer
95 views

How did people who were living far from the sea obtain iodine during the Middle Ages?

Knowing that today iodine comes either from fish products or (artificially) enriched table salt, how did people who lived far from the sea survive before (especially during the the Middle Ages)? Edit ...
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22 views

Is body energy production and consumption cyclical?

If we look into how energy is produced by the humans, it always involves some kind of periodicity: fuel combustion rotates engines, water rotates turbines, nuclear chain reactions heat up water, which ...
2
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1answer
42 views

How does the human body use energy?

As far as I know the glucose gets processed from carbs and fats and as a result carbon dioxide, water and "energy" are released. The carbon dioxide and water are expelled by the body, and then energy ...
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2answers
108 views

Plotting metabolic networks?

I need to draw a map of the core metabolism of E.coli. Associated with each reaction in the map I have a number that indicates the flux through this reaction. I want the map to reflect these fluxes ...
4
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1answer
53 views

Oxidation means inflamation?

All right, I was reading article on nutrition, that focussed on content analysis of pastry-like food product for kids. I have to say that I am not sure this article would pass the imaginary smell ...
4
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1answer
121 views

How efficient is the human body at metabolizing food?

My friend and I were having a discussion over how "efficient" human digestion is. If a human ate a 1000 calorie hamburger, how many of those calories (how much energy) does the body process into ...
2
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4answers
3k views

Why do we weigh less in the morning?

At first I thought it may be related to physics. You know, in one half of the day, the gravity changes, and the scale shows a different weight than the other. Then at night, gravity intensifies, and ...
4
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3answers
398 views

What is the mechanism of oxygen uptake in E. coli?

How does E. coli uptake oxygen? Most of the literature I found is concerned with response to oxygen level supplied in the medium, as opposed to how much is actually transported inside. Can they shut ...
3
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1answer
115 views

The smell from eating asparagus

I am wondering about one thing. I have read different accounts of this (prior to reading it on Wikipedia), so I am wondering. Here are the two versions I have read: asparagus leads in a certain ...
3
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1answer
92 views

Consumption of NAD+ in glycolysis

Out of 10 steps in glycolysis, only one reaction- Glyceraldehyde 3-phosphate (G3P) to 1,3-bisphosphoglycerate (PGP), uses NAD+ and thereby producing NADH. Furthermore, this very step is solely ...
2
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1answer
53 views

naturally occuring fatty acids

The double bonds in naturally occurring fatty acids present in our body are in cis configuration while the enzymes for beta oxidation can act on trans double bond. Then what will be the significance ...
0
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1answer
89 views

What organism most efficiently converts a given quantity of mass into heat?

Question I am trying to answer: In the popular film The Matrix, heat given off by humans is harvested as an energy source. I wondered, if this were possible, would humans be a good organism to ...
3
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1answer
36 views

bacterial cell wall degradation in humans

can human degrade the D-amino acid present in bacterial cell wall, I'm confused about it i have read somewhere that human can do so.If yes than why we need antibiotic to kill bacteria???If it is not ...
4
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2answers
168 views

Breakdown of energy expenditure at the level of a single cell

The metabolic rate measures how much energy an organism expends over a unit of time. Its breakdown for the human body in terms of its functions is well documented : so much for the heart, for the ...
4
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2answers
89 views

Where can I find a list of common enzyme cofactors and/or co-enzymes?

Where can I find a list of enzyme cofactors and/or co-enzymes, ordered by how common they are? For example, $O_2$, $H_2O$, $ATP$, $ADP$, $NAD$, should be ranked in the first places, because they ...
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22 views

desaturation in fatty acids [duplicate]

humans are unable to synthesize EFA what is the reason behind it that humans cannot introduce double bond between C-10 and the methyl terminal?
2
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0answers
65 views

Why Mammals are unable to produce Essential Fatty Acids?

While we have to get them from our diet and if they aren't taken in our diet we will face disease.Then why we don't have the enzymes which are require for EFA synthesis???
2
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1answer
45 views

Currency metabolites vs. current metabolites: What's the right term?

I have seen the two terms currency metabolite and current metabolite used interchangeably. Is there a consensus on which is the ...
8
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1answer
149 views

How should I feed and keep an ant queen?

I have captured wandering ant queen. I guess she was just fertilised and was looking for a place to start a hive. I'd like to create my own ant hive in artificial environment. I unfortunately only ...
2
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1answer
154 views

what is the margarine metabolism in our body?

margarine is commonly used food ingredients that contribute to both inflammation and obesity , but actually I want to know the margarine metabolism in the human body I can find some resources talk ...
4
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1answer
88 views

Do mitochondria use ATP in order make another ATP from glucose?

Do mitochondria use ATP in order make another ATP from glucose, or does it use another source of energy to convert glucose to ATP?
2
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1answer
214 views

Anaerobic respiration choice in E. coli

Under anaerobic conditions E. coli has two options to generate ATP: fermentation (substrate-level phosphorylation), and respiration (proton gradient, chemisomotic phosphorylation). Which is favored? ...
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Regulation of Cra protein level in E coli

Catabolite Activator/Repressor, Cra protein (formerly known as Fructure Repressor FruR) plays a significant role in central carbon metabolism of E coli. Its activity is inhibited by ...