Hot answers tagged

220

Short answer Blue color is not only rare in edible organisms - Blue color is rare in both the animal and plant Kingdoms in general. In animals, blue coloring is generated through structural optic light effects, and not through colored pigments. In the few blue-colored plants, the blue color is generated by blue pigment, namely anthocyanins. The reason for ...


112

Although @AliceD's answer is a great simple demonstration of the rarity of blue in our natural world, there's likely a more nuanced/technical reason. Short answer Blue light was the most available wavelength of light for early plants growing underwater, which likely led to the initial development/evolution of chlorophyll-mediated photosytems still seen in ...


79

The reason is simple: Chocolate contains cocoa which contains Theobromine. The darker the chocolate is (meaning the more cocoa it contains) the more theobromine it contains. This is a bitter alkaloid which is toxic to dogs (and also cats), but can be tolerated by humans. The reason for this is the much slower metabolization of theobromine in the animals (...


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 ...


47

Sugars in 100% natural fruit juices are chemically the same as in whole fruits. They mainly include glucose, fructose and sucrose: Apple nutrition data (expand the carbohydrate section) Apple juice nutrition data Sugars in whole fruits are "incorporated" into the fruit, which means the digestive system first needs to physically decompose the fruit and then ...


42

Adult butterflies don't eat! I mean.... not in the sense of chewing on food. They rather drink. They get their nutrients via ingestion of liquid substances. Their mouth consists of a long tube called a proboscis that acts as a straw. What do butterflies feed on? The vast majority of butterflies eat nectar from flowers. Many species are quite specialized ...


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 ...


33

I believe that MattDMo's hypothesis is incorrect. Only one group of ants, the Attini tribe, cultivates fungus as a food source. This group is exclusively a New World group, thought to have originated in the Amazon rainforest and spread out from there. I see from your profile that you are located in India, which is outside the range of the fungus-...


30

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 ...


26

The list of ingredients on the can mentions "Zuckerkulör," which is caramel colour, which can have 2 kcal/g, according to one producer. Next, there is "Citronensäure," which is citric acid, which can, as other organic acids, have 2-3 kcal/g, according to this source. There is also taurine, which is an amino acid-like compound, so it could, like proteins, ...


25

The toxic ingredient in chocolate is in the mythylxanine class, a substance called theobromine. It is much like theophylline; overdoses of theophylline used to be very common before the advent of inhalers for the treatment of asthma. (Chocolate also has some caffeine in it, which may exacerbate the effects of theobromine.) As @Chris stated, it is only slowly ...


24

Several species of the order Lepidoptera don't feed at all in adult form, surviving entirely on the reserves made while they were larva. Two examples I'm aware of are the Atlas moth (as well as most of the family it belongs to) and the clothing moth. Also, many butterflies and moths which normally do feed stop doing so after the mating (for males) or after ...


22

There are a number of papers studying the ability of fungi to metabolize keratin, the primary structural component of nails (as well as skin and hair). Ants are also known to cultivate fungi for nutrients, so this may simply be a case where the ants are bringing food for their "farm animals."


20

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. ...


20

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 ...


20

The issue is that it is not always a cycle, when you drain wetlands or burn forests to make more farmland that's not a cycle that is permanent change. A change that can continue having effects for centuries. Then of course you have petroleum fuel used to run tractors and the production of fertilizer which are often not cycles either but pure extraction. ...


19

The red colour of blood isn't actually to do with food at all. The primary purpose of the blood is to carry oxygen to all the cells that require it to release energy. Red Blood Cells are filled with an iron containing pigment called haemoglobin. When it has oxygen bonded to it, haemoglobin has a bright red colour - it is this that gives blood its red ...


19

Yes, mantises hunt cicadas... Mantis eating cicada. Source: Dreamstime. ...and yes, orioles hunt cicadas too... Oriole eating cicada. Source: Bird Ecology Study Group. .., and what may be more relevant to your idiom: orioles prey on mantises. Oriole eating mantis. Source: Sustainable Adventure.


18

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 mg/...


17

One of the most common toxins in mouldy food/bread is aflatoxin. The exposure to high amount of aflatoxin can lead to acute aflatoxicosis with fulminant hepatic failure and even death. While mild exposure to aflatoxin could be asymptomatic, it is better not to take a chance considering possible complications (citation from the link above): Aflatoxins ...


16

I'm sure it varies wildly based on the animal and what they're eating. In general, if in the course of an animal's natural feeding process it picks up a little dirt, it has evolved to cope with that. Animal's behaviors and guts have evolved to fit their food source and lifestyle. For a behavioral example, seals will eat rough rocks to help breakdown bones ...


15

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 ...


15

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 ...


15

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 cells....


14

1 billion hives (at 10,000-50,000 bees/hive this is 10-50 trillion bees) Managed: 100 million hives Based on country-level data from FAO, supplemented for a few countries with Apiservices, in 2011 there were about 80 million managed hives. Because FAO lacks any data for some countries, and other countries under-report (for instance US figures don't ...


14

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. ...


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

Generally, cold suppresses sweetness. As an example, consider soft drinks that are usually served cold: they taste sweeter when warm (like you said with your examples of drinks). Our taste receptors send a stronger signal to the brain when activated by warmer substances and so the perception of sweetness, in this case, is lessened when we consume cold food ...


12

There's a fantastic database available from the United States Department of Agriculture that includes almost 9,000 common foods, including their nutritional information. This database is searchable and available from the USDA Agricultural Research Service. Here is a link for the online searchable database. Within the database you are able to search for a ...


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