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8 votes
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Why are fatty acids consisting of even number of carbons predominant?

In short, it's because fatty acids are made from two-carbon blocks. The way that most organisms make fatty acids is by the successive addition of two-carbon units (acetyl-CoA). So we usually get ...
julianstanley's user avatar
7 votes
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Why do fully grown organisms need protein intake?

Protein is polymerized amino acids. Humans do not require protein intake, but certain essential amino acids are required. These essential amino acids are usually obtained through protein intake, ...
DavePhD's user avatar
  • 756
5 votes
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How much nucleoside triphosphate is required to form one peptide bond during protein synthesis?

Although the question shows considerable effort to achieve clarity, the way it is phrased as: How many molecules of nucleoside triphosphate… [does] it take to release enough energy still allows ...
David's user avatar
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4 votes
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How can cane sugar sucrose be different from beet sugar in regard to carbon-13 content?

The differential uptake of different isotopes of carbon is covered well at: https://en.m.wikipedia.org/wiki/Fractionation_of_carbon_isotopes_in_oxygenic_photosynthesis Plants have a lower proportion ...
Polypipe Wrangler's user avatar
4 votes
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Essential amino acids

Bacteria and plants are able to synthesize all amino acids, as they are capable of nitrogen fixation. If animals eat plants, they get the essential amino acids needed for their proteins. Humans get ...
SeRe's user avatar
  • 425
3 votes
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How many proteins do all human ribosomes together produce per hour?

Regarding protein synthesis rate, here's an attempt at an estimate from bioenergetics: ATP turnover in the human body is consider to be about 100 mol / day. Protein synthesis is estimated to require ...
Roland's user avatar
  • 5,705
3 votes

Nicotine levels in non fruit/edible parts of plants (that are not tobacco)

Tomato leaves have something like 184 ng/g of nicotine, in the same ballpark as tomatoes (the fruit) and not close to tobacco. I think this is not peer-reviewed, but it cites other papers that are: ...
DCP123's user avatar
  • 31
2 votes

Relative roles of ATP and NADPH in anabolic and other processes

Preamble I don’t know where you read the statement “NADPH is... the main agent necessary for anabolic reactions”, but out of context it is very misleading, and it is difficult to envisage ...
David's user avatar
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2 votes
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Determine whether aromatics originate from polyketide or shikimate pathway

Aromatics that stem from the Shikimat Pathway result in a structure like this Whilst aromatics originating from the Polyketide Pathway have an alternativ structure in the distribution of the OH ...
idkfa's user avatar
  • 195
2 votes

Which mammals cannot synthesize taurine?

It is a misconception that cats cannot synthesize taurine. Cats can synthesize taurine, just like other mammals, but not enough of it to make up for an entirely taurine-deficient diet. Cats (and ...
Gwen's user avatar
  • 883
2 votes
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does life make or break?

Metabolism ≈ Anabolism + catabolism Metabolism is the set of all chemical reactions happening inside a living body. These reactions can either breaks down big molecules and build up big molecules. ...
Remi.b's user avatar
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2 votes

A molecular marker for global protein synthesis

The answer will not satisfy you. The truth is no protein marker will do. On one hand you seem to be looking at some individual, representative protein, which you could measure by immunoblot. But most ...
nvja's user avatar
  • 1,150
2 votes

Nicotine levels in non fruit/edible parts of plants (that are not tobacco)

I take issue with the previous answerer's assertion that it is extremely unlikely that previous research on nicotine concentrations has ever been performed; in fact, it was very well established ...
kheironiscus's user avatar
2 votes
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Are all/most/any membranes comprised of lipids from the smooth ER?

It sounds like we're mainly interested in phospholipids here, as they're the main component of cell membranes. Since your question didn't specify, we'll talk about Bacteria/Archaea and Eukarya ...
Dubukay's user avatar
  • 808
2 votes

Why do fully grown organisms need protein intake?

A fully grown organism is subject to senescence and on a narrow perspective one of the signs of aging is the accumulation of large amount of lipofuschin. In unstressed situations protein homeostasis ...
user 33690's user avatar
  • 1,955
2 votes
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Reverse protein biosynthesis in nature

In biological systems, the central dogma states that genetic information flows from DNA to RNA to proteins, and the reverse process, synthesizing DNA or RNA from proteins directly within cells, does ...
Chris's user avatar
  • 51.7k
2 votes
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Difference between AjuA and ajuA in biosynthesis

It's just the nomenclature: Bacteria: Gene symbols are typically composed of three lower-case, italicized letters that serve as an abbreviation of the process or pathway in which the gene product ...
canadianer's user avatar
  • 17.8k
1 vote

In ketogenesis, why is acetacetyl-CoA not directly hydrolized to acetoacetate in ketogenesis?

After further checking, I found that HMG-CoA synthase rather than HMG-CoA lyase is the enzyme which is regulated. This enzyme also plays a vital role in cholesterol synthesis. HMG so produced can ...
Richard B. Walker's user avatar
1 vote

In ketogenesis, why is acetacetyl-CoA not directly hydrolized to acetoacetate in ketogenesis?

I believe it is related to the fact that the enzyme HMG-CoA lyase is regulated by glucagon (activates) and insulin (inactivates). It appears that this extra step was added so the pathway can be ...
Richard Walker's user avatar
1 vote

What is the difference between gene expression and protein synthesis?

According to the homonymous article of Wikipedia Gene expression is the process by which information from a gene is used in the synthesis of a functional gene product. These products are often ...
LinuxBlanket's user avatar
  • 1,313
1 vote

Nomenclature of enzymes involved in synthesis of glutamine

Probably a mistake in your notes, or in the lecture notes for the class, but not a very important error in either case aside from the confusion it has caused you. See the wikipedia article on ...
Bryan Krause's user avatar
  • 45.9k
1 vote

How many proteins do all human ribosomes together produce per hour?

For your first question I think @Michael_A has explained why this question can't be answered. And for the second one, I quote from bscb.org : Ribosomes are found ‘free’ in the cytoplasm or bound ...
Bilal's user avatar
  • 761

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