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49

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 ...


35

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 ...


19

To elaborate on A random zoologist's answer, the problem is that the human digestive system does not contain any cellulase enzymes. Cellulases are a class of enzymes that break down cellulose, the chief structural component of plants. You might be able to obtain a small amount of nutrition from grass or other cellulose-rich materials, but as the plant cell ...


19

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

Of course eggs are not vegetarian. Eggs are, well, the eggs of chickens (usually). Chickens are animals so their eggs are animal matter as well. Whether or not the egg has been fertilized is completely irrelevant, eggs are chicken just as much as drumsticks are. The color of the egg has nothing at all to do with it. All eggs are, by definition, animal ...


14

The more "dangerous" properties of spicy peppers are chiefly due to capsaicin. Sigma-Aldrich sells purified capsaicin, for which they provide safety information, including an MSDS. Most of it is the usual, unsurprising set of warnings about irritation to eyes and the respiratory system. However, there are LD50 numbers: LD50 Oral - rat - male - 161.2 ...


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 ...


13

While poison affects not every organism equally, plants did develop some poisons to avoid being eaten. However, if you look at the great multitude of so-called secondary metabolites, most of them are poisonous to either viruses, bacteria, fungi or other microorganisms, or insects, or even other plants. Plant evolution just hasn't had time to adapt to humans. ...


11

The basic reason is osmosis, the tendency of solutes to move from an area of high concentration to one of low concentration across a permeable barrier. So, ingesting large amounts of salt results in a high sodium concentration in the blood stream. This in turn causes water to enter the blood vessels by osmosis. More water in the blood means a greater volume ...


10

During putrefaction of animal tissue, lysine is decarboxylated into cadaverine and arginine is decarboxylated into putrescine. These compounds are deemed to be toxic. A serving of meat contains 8 g of protein, corresponding to 640 mg lysine and a little bit less of arginine. Let's go straight and say that a spoiled meat serving contains 640 mg cadaverine ...


10

First, there are two different isomers of the lactic acid, the L(+)- and the D(-)-form. Both differ in the position of the OH-group in the molecule: Both turn polarized light in different ways, the D(-) to the left and the L(+) to the right. The physiological form of lactic acid for the human body is the L(+) form, which is taken up in the gut and then ...


9

I wouldn't be suprised if no one has hard data on this. In any case there is more than one answer to this question. Niches are defined more than one way. In the narrowest definition, the niche might be defined as the ability of the different trees to grow in different terrains or be eaten by different animals in the same environment. I can't comment on ...


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

Evolution is not that simple. There is no selective pressure for a feature if it does not ultimately in some way benefit reproduction or the offspring. Vegetables are healthy for us now because we live much longer than we used to in an environment not dominated by us, and they contain many nutrients which help to sustain a healthy body beyond, say, 50. ...


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

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

Quite a bit can be absorbed through the mouth. Most commonly, starches are broken down to maltose (two glucose molecules formed by a condensation reaction) and are easily absorbed by the bloodstream. A lot of other factors balance into this, ie pH, lipid solubility, and molecular weight. Generally, if a substance is easily dissolved in saliva, it can be ...


7

The reason for this is the oxidation of phenol residues in the banana (for example in the yellow color) which get oxidized by the enzyme Polyphenol oxidase (PPO) to melanins. The scheme (the image is from this website on food browning) looks like this (you can of course also use more complicated substrates): For further information, see these references: ...


7

They don't eat little. Consider the volume of milk / food they consume as a ratio of their weight. Quite the contrary they are ravenous machines and their consumption is much higher than an average adult. All cellular energy comes from the hydrolysis of ATP, and the production of ATP comes from the breakdown of glucose. The glucose comes from a sugar found ...


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, ...


6

Here is a website that presents very accuerately the tree of life: tolweb.org/tree Yes, they have a common ancestor just like any other living things! How closely related are they? Both species are: Eukaryotes (cells with a nucleus) Archaeplastidae (plants) Angiosperms (flowering plants) Then, they split their way! Here is the tolweb.org page that ...


6

Well, humans can eat grass, but it will not be digested. Cause to digest grass our body needs different kind of enzymes, which lack in humans so they can't digest grass directly although humans can eat grass, but not recommended. Similarly our body has different enzymes to digest wheat and beans etc. Also remember rice, wheat and beans are fruit, not plant. ...


6

Wheat and other grasses are very significant sources for human nutrition. Grass seeds are digestible; seeds have to digest themselves to sprout, with very little biochemical machinery. Human civilization is founded on the ability to cultivate grass to eat. It is due to pepsin that a cellulase supplement would not help to digest grass stems and leaves. ...


6

There are several ways you could go about identifying species through DNA. If you want to do everything yourself, the simplest option in terms of equipment needed consists of evaluating fragment lengths observed during gel electrophoresis after amplifying specific DNA sequences using PCR. If you are content with some outsourcing, you can also send DNA ...


6

Indeed, many plants produce molecules which are poisonous to things that eat that plant (insect, mammal, bird) in the "hopes" of preventing that animal from eating them. In this sense, even eating the "right" fruit may be dangerous (if that individual plant happens to be an exceptionally vigorous producer of the poison, or because the eater is weakened for ...


6

Is consumption of blood more "dangerous" compared to meat? Actually yes, a simple high dose of blood is enough to kill. The cause is, though it is most important thing to live when flowing the vessel, it's highly toxic when consumed. There are high chances of getting haemochromatosis or Iron overload. Source and More on this: ...


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 ...


5

As mentioned by nico in his comment, this infographic is very misleading in that it presents quite uninteresting data in a way as if it was a sensation. It claims the average meal drink has been soda which has increased by 6 times in size. Then it claims most of the volume is water. This is of course true. But while a substance solved in water barely ...


5

The ancestral apple is thought to originate in what is now Kazakhstan. See this report from the USDA on this topic. Those early apples were small and likely eaten more often by non-human species. Pears: From Wikipedia: The genus is thought to have originated in present-day western China in the foothills of the Tian Shan, a mountain range of Central Asia, ...


5

There is a very plausible explanation here. Basically, it explains that meat colour is due to the protein myoglobin (a haem-containing protein related to haemoglobin). There are two types of skeletal muscle: fast-twitch and slow-twitch (Wikipedia). Slow-twitch muscle is red muscle because it contains lots of myoglobin. Fast-twitch muscle is white muscle, ...



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