Tag Info

Hot answers tagged

53

The answer to your question is yes it is certainly possible. At one time it was thought that there was something special about "organic" chemicals which meant that they could not be artificially synthesised out of fundamental elements. In 1828 Frederick Wöhler synthesised urea (CO(NH2)2) which is often taken as the first demonstration that the organic v ...


36

Living organisms can be divided into hetrotrophs and autotrophs. Autotrophs like plants and algae are able to produce complex organic compounds from relatively simple inorganic components. They are satisfied with sunlight, water and other abiotic stuff and do not need to consume "life". We -- along with all other animals -- are not autotrophs, but ...


21

Even on a purely synthetic diet, your body would still use living cells as an energy source. Our bodies contain more bacterial cells than human, mostly contained in our gut. These microbes process any nutrients we ingest and when they die, we absorb their cellular components as nutrition. The lining of the gut is the most rapidly dividing population of ...


14

Your question is phrased somewhat ambiguously as to whether you're asking about the theoretical possibility, the feasibility, or the practical ability in everyday life. 1) Theoretically, yes. It is chemically possible to produce all substances that humans need to survive without the use of living organisms in the process. In the end, biological systems use ...


10

does the microbiome affect food metabolism? Most definitely (and not surprisingly). The Arumugam paper [1] notes that The drivers of [enterotype 1] seem to derive energy primarily from carbohydrates and proteins through fermentation, … because genes encoding enzymes involved in the degradation of these substrates (galactosidases, hexosaminidases, ...


9

Shortest answer: there's nothing special in human biology, you could totally make it Short answer: Bachelor chow! I would totally buy this stuff if they made it. The closest I have now to bland, flavorless, zero thought/effort food is Wheaties. longer answer: Seriously though, dogfood for humans wouldn't be that hard to make. If you just took everything ...


9

Depends on how you define "life"? Is unfertilized chicken eggs alive? What about cow milk? Well there are bacteria in it. What if you get rid of that bacteria? Then some people would not be able to utilize lactose... Also as Bez mentioned rice grains are quiescent, meaning they are in a dormant state and not really "alive" but again depends on how you ...


8

Bioavailability is a concept which applies to nutrients and drugs which pass through first-pass metabolism, i.e. orally (and to some extent nasally) consumed substances. Anything absorbed in the gut first passes through the liver before reaching the rest of the circulation, and both the gut and liver may metabolise it to some extent. The liver in specific ...


8

Yes. Rob Rhinehart has developed what he refers to as "a food substitute intended to supply all of a human body's daily nutritional needs, made from powdered starch, rice protein, olive oil, and raw chemical powders" which he calls Soylent. It was developed and tested largely in 2013, crowdfunded late 2013, and is expected to start shipping in 2014. Tests ...


7

Yes, the microbiome affects food metabolism and the diet affects the composition of the microbiome. +1 to Konrad for his response. This is an area of research in which I and colleagues are engaged. Frankly, it is easier to assess the changes to the microbiome based on diet rather than looking at the fecal material to determine (unused) metabolic energy or ...


7

Question: Is it possible for humans to live healthy long lives without eating any type of life, i.e no animals, no plants? First, according to a definition of a living organism(biology-online), milk is not live, because it does not have an ability to reproduce itself, among other... My claim: If you consider milk and honey non-live (no DNA), then, yes, ...


7

The bacteria in the foregut of cud chewing animals (e.g. cows) provide enough B12 and other B vitamins. Uptake of B12 happens mainly in the small intestine. There are lots of bacteria in the human intestine but most fermentation of plant matter happens in the hindgut. Hindgut fermentation also produces B12 but since this happens past the small intestine it ...


6

There is not very much transport of ions or water through the upper layer of the skin, mainly responsible for that is the stratum corneum (SC). Through this layer you will get only with small lipids and also substances which are able to penetrate the lipid layer of the cells like chloroform or DMSO. I think therefore that it is pretty unlikely that you can ...


6

The mineral content in tap water differs from area to area as well as the source. The mineral content in bottled water is regulated by the companies that manufacture them, in particular the Mg and Ca content(reference). Death rates tend to be lower in areas with tap water containing higher levels of Ca and Mg. It has been shown that deficiencies in ...


6

No. It is possible but extraordinarily impractical to nourish yourself without killing animals, plants or even bacteria, as many have explained in detail. However, your immune system constantly kills pathogens that infect your body. What's worse, the macrophages literally catch and eat these bacteria alive, so you are very much "consuming" them. You could ...


6

Detritivores consume (eat) detritus. Saprotrophs feed on dead organic matter by the means of extracellular digestion. Saprozoic organisms are protozoans that are saprotrophs. This actually comes from an obsolete classification of plants and animals where bacteria and fungi were grouped with plants and were therefore called saprophytes if they are ...


5

No it is not possible. Humans are heterotrophic organisms, which means that we use organic molecules (i.e., food) as a source of nutrients and energy. We use the nutrients to add mass to our bodies. These nutrients are the familiar carbohydrates, proteins, lipids (fats), etc... During digestion food is broken down into simpler organic nutrient molecules ...


5

The quantity of nutrients the body requires takes much more physical space than can be included in a simple pill or injection (used only a few times a day). But nutrition can be provided by IV (intravenous administration), and it is used today for some medical conditions. When the IV completely substitutes for normal digestion, it is called total ...


5

Essential "minerals", i.e., metal cations are magnesium, zinc, iron, potassium, sodium, manganese, molybdenum, selenium, cobalt, copper and even calcium, as we lose a tiny amount of it through urine and sweat. They are all "stored" in some way, but only temporally, so some amount has to be taken up daily. It would show only weeks later, however, if you have ...


5

Does this look like the same bug to you ? . This one is a bulb mite, Rhizoglyphus robini, see here.


5

In this article it is described that starved macrophages 'consume' heat inactivated bacteria through phagocytosis with enhanced ability. Starving can also induce (macro)autophagy and the pathways are connected with phagocytosis,in the macrophages under investigation it was shown that autophagy did not play role in the enhanced ability of phagocytosis. The ...


5

I've found an old paper using radioactively labeled bacteria to track their fate in macrophages. According to the data, both $^{14}$C and $^{32}$P are reutilized in the host cell. COHN ZA. (1963). The fate of bacteria within phagocytic cells. I. The degradation of isotopically labeled bacteria by polymorphonuclear leucocytes and macrophages. J Exp Med. Jan ...


5

Potassium cyanide is added to the cobalamins produced by bacteria to give rise to cyanocobalamin. CN is strongly bonded to Co and will not easily dissociate, thereby making this form of B12 inactive. Therefore, it has been argued that cyanocobalamin is not a good vitamin supplement and other variants such as hydroxycobalamin or methylcobalamin should be ...


5

Cellular metabolism describes the process by which the products of digestion (amino acids, fat derivatives and the hexoses/ monosaccharides fructose, galactose and glucose) are chemically modified to yield usable energy. They differ in term of which pathway they undergo during metabolism, before becoming a part of the citric acid (TCA) cycle. You ...


5

One thing to remember when you uproot a plant is that some of the smallest structures break off most readily. What you will usually see after uprooting the plant are the largest parts of the root structure, but there are often smaller parts which have broken off. Root structure is highly variable, but the general idea is that one or more primary trunk-like ...


4

Much like Daniel Standage suggests, I think "edible" is more inferried than defined, sort of like looking at a black hole - its absence is defined by the activity around it. Human bodies are capable of metabolizing lots of compounds that become poisonous pass some threshold. In medical terms there are LDmin and MLD and LD50: miminum Lethal Dose, Median ...


4

As far as I know, edibility (wow, I'm surprised that passes the spell checker!) is not a strictly defined term, biologically or otherwise. Humans have been around eating and drinking stuff long before the scientific method was around to study this question rigorously, and before there were regulatory agencies charged with approving new products as "safe." As ...


4

I'm not quite sure what you mean by regardless of x and y being out of balance. Surely it would make more sense to assume you gain 0 weight if x and y are balanced? The prime reason why people get obese is probably because x and y are not balanced for them (there are other reasons though, as well as reasons why people can have it imbalanced and still ...


4

For what concerns amino acids, mice rapidly reject meals that are not balanced in essential amino acids and continue to look for other kind of foods. This behavior is called aversion response and it is an adaptive phenomena that can be observed already 20 minutes after exposure to the unbalanced food. The mechanism involves brain sensing of uncharged tRNAs. ...


4

The name used frequently for this phenomenon is "Post-lunch dip". "The post-lunch dip is a real phenomenon that can occur even when the individual has had no lunch and is unaware of the time of day. This dip has its roots in human biology, and may be linked to the size of the 12-hour harmonic in the circadian system. It is certainly exacerbated by a ...



Only top voted, non community-wiki answers of a minimum length are eligible