uKnoWhy.com

U know why the fish stinks?

admin — Wed, 21 Apr 2010 23:31:39 +0000

The smell of fish (fish odor) is not due to the fact that the fish died and then begin it’s decomposition but is due to trimethylamine, a compound that is volatile form after the death of fish, some proteolytic bacteria (demolition of protein structures) of the genera Achromobacter, Pseudomonas, Micrococcus, Bacillus putrefaciens Altreromonas and begin to colonize the meat.

The process continues on a regular basis over the period of edibility of fish, and this explains why the smell (fish odor) increases with time. Then stabilizes.

Cool?

The measure of the amount of trimethylamine is the most common for determining the freshness of the fish: if less than 5.10 mg / 100 g, according to experts FAO (UN Food and Agriculture) should be marketed.

The intensity of the smell indicates the degree of freshness and therefore quality fish.

Curiosity
It is not only the fish that lay decomposing on odor, there is trimetilaminuria, in people suffering from a disease that may have genetic origin, it spreads the same scent: in fact they are deficient in enzymes that transform trimethylamine, it is naturally present in the human body, in odorless compounds.

U know why the fireflies glow?

admin — Tue, 10 Mar 2009 13:04:01 +0000

The firefly is an insect which is particularly known for its characteristic luminescence. This animal has special abdominal organs, which cause a chemical reaction with the organic synthesis of an enzyme called luciferasi.

The light produced is useful because from these insects it can be exploited as a mean of communication between individuals of the same species, probably as a sexual recall as well, that could draw the prey too. It is curious to note that the adult insect issues, generally, intermittent light, while the larvae shine light sets.

U know how to calculate the age of a horse?

admin — Sun, 08 Mar 2009 14:20:30 +0000

The age of a horse is determined by observing its teeth, because the adult male horse has 40 and the female 36 (because of missing brackets) as’ distributed: 12 molars, 12 premolars, 4 bands, 12 incisors, which are also divided into: 2 Picozzi, 2 median and 2 cantons (or lateral). The spaces between the incisors and the premolars are called bars.

When sprout the first front teeth the horse reaches its first birthday. At 4 years there are 8 and 5 there are 12. Given that his life expectancy is around 25/30 years, to estimate the ‘age’ is based on the wear of the teeth that starts from ‘age’ of 8 years. Indeed, if the chewing is a continuous consumption of the dental board, but is offset by a steady growth of the tooth.

Then you can determine with accuracy the discreet age of the horse according to the shape of the board of dental lower incisors.

U know why ‘ostriches’ hide their heads in the sand ?

admin — Sat, 22 Nov 2008 13:10:14 +0000

The reason for this behavior on the part of ostriches is ignored by everyone, why? Simple … because it’s false! Indeed, the popular belief that ostriches put their heads in the sand in case of danger, is wrong and has never been recorded.

However, when there is no other possibility of escape evident, a bird can lie down on the ground with head and neck stretched forward and remain firm in the hope that it is ignored by his enemy. This strategy has similarly taken by a bird in hatching when feel that the danger is nearby.

But it is plausible that this belief is born from a visual interpretation wrong: in fact, when an ostrich lowers his head between the foliage to eat, it seems, for an optical effect, like he has its head hidden between the sand.

U know why there are most months 30 or 31 days long ?

admin — Wed, 19 Nov 2008 12:45:08 +0000

This has resulted from a compromise. Initially, months were mostly 29 days long and the average length of a month was 29.5 days which is the time taken by the Moon to orbit the Earth. However, this resulted in a year of only 354 days while the orbital period of the Earth is 365.2422 days. As a result, the calender became out of sync with seasons which was bad. This was initially corrected in an arbitrary way by adding a 13th month, but soon the calender was thrown into severe confusion.

In 46 B.C., Julius Caesar reformed the calender by ordering the year to be 365 days in length and to contain 12 months. This forced some days to be added to some of the months to bring the total from 354 up to 365 days. To account for the extra 0.2422 days, every fourth year was made a leap year. This made the average length of a year to be 365.25 days.

However, the Julian year still differs from the true year and by 1582, the error had accumulated to 10 days. So, 10 days were dropped from the year 1582 so that October 4, 1582 was followed by October 15, 1582. In addition, a modification was made that century years that were not divisible by 400 would not be considered as leap years. For example, 2000 would be a leap year while 2100 would not. This made the year sufficiently close to the actual year and this calender is called the Gregorian calender.

As the year is now set up to follow the seasons accurately, it no longer follows the phases of the Moon.

U know why ‘you cry cutting the onion’ ?

admin — Tue, 18 Nov 2008 21:58:40 +0000

In onion there are molecules that contain one or more of sulfur atoms: the organic sulphides. When cutting the onion these sulphides are combined with another substance present in different layers, “the allinasi enzyme”, which degrades amino acids and volatile odorless. These amino acids, reacting with water covering the cornea, are transformed into acids, mainly sulfuric and sulphide. As corrosive substances, the eye tries to rid activating the lacrimal glands. From the’90 in different parts of the world , it attracts the attention of scientists, agronomists and geneticists. How it is possible to avoid tearing ? . In a research to assess the volatile components in some onion cultivars an investigator at the University of Naples, Giancarlo Barbieri, showed 46 volatile compounds, including many sulfur compounds, aldehydes and some alcohol. They noted differences between varieties of yellow and white tunic. For example, the level of volatile compounds in cultivar Density is about twice that in pure Blanco and Reddy. The cultivar late or have a Serb acid content Pyruvic twice as sweet. E ‘result that even the mineral sulphate fertilizer can help improve the level of alcohol pungency, especially in the case of onions. A researcher of Georgia has shown experimentally that after the administration of calcium sulfate to the soil concentration of acid in Pyruvic bulbs has doubled.

U know why the “fractals” are called so ?

admin — Tue, 18 Nov 2008 21:27:21 +0000

The history of fractals in the strict sense is fairly recent. Suddenly opened in 1975 with the revolutionary publication “A Theory of Fractal Sets” of mathematician Benoît Mandelbrot, which became the basis of its fundamental text and manifest.

In “The Fractal Geometry of Nature” Mandelbrot, has coined the term fractal which derives from the Latin word “Fractus” (split), because the size of a fractal is not whole. The fractal geometric figures are characterized by repeated indefinitely until the same reason on an ever smaller scale.

The characteristic of these figures, a feat which derives its name, is that although they may be represented (if you do not claim to represent endless iterations, ie processing for which it retains a special plea geometric) in a conventional two – or three dimensions, their size is not whole. In fact, the length of a fractal “plan” can not be definitively measured, but depends strictly by the number of iterations in which you put the initial figure.

Mathematicians as Waclaw Sierpinski, David Hilber, Georg Cantor and Helge von Koch gave shape to the first fractals, mainly for the pleasure of abstraction, without having the idea of ultimate meaning that would take. Many of them considered these pathological forms, cumbersome or even unpleasant. They would be certainly surprised to learn that today are remembered mainly thanks to those forms that both disgusted them!

Some of these pioneers had good reasons for not appreciating those geometric aberrations. They had indeed realized that Mandelbrot had revealed something that called into question and threatened some of the cornerstones of their discipline. We know now that the era in which these scientists lived (1875 – 1925) was, in fact, a period of crisis for mathematics. Increasingly, the mathematical encounters forms that were unsettling the concepts of space, area, distance and size.

U know why one minute has 60 seconds?

admin — Tue, 18 Nov 2008 20:53:48 +0000

With the birth of mechanical watches, around the thirteenth century, it was established the habit of splitting time in 60 smaller parts, all equal, each of which was called in Latin “pars minuta prima” which means “first small part” then cut short ‘minutes’, and these in turn were divided into 60 shares still other smaller, each of which was called, in Latin, secunda pars minuta (second small part), then cut short’ second ‘.

The choice of the number 60 is traced back to Sumerian, which had divided the circle in 360 equal parts, each of which later was called degree, from a Latin word meaning “step”.
60 and 360 numbers were regarded as “magical” granted by the gods , because easily divisible in so many different ways without leaving the rest

U know why it is used to give “Easter eggs”?

admin — Tue, 18 Nov 2008 20:09:27 +0000

The eggs, perhaps because of their shape and substance very particular, have always played a unique role, the symbol of life itself, but also the mystery, almost sacred. Already at the time of paganism in certain beliefs, Heaven and Earth were considered two halves of the same egg, and eggs were the symbol of the return of life. The birds in fact were preparing the nest used to contain the eggs: then everyone knew that the winter and the cold had passed. The Greeks, Chinese and Persians exchanged them as a gift for the Spring festival, in ancient Egypt decorated eggs were exchanged at the spring equinox, for starting the “new year”, yet when the year was based on the season. The egg was seen as a symbol of fertility and almost magic, because the then inexplicable birth of a living being by an object so particular. The eggs were considered by the special items, and were buried beneath the foundations of buildings to ward off evil, bring in the womb by women which was interested to discover the sex of the unborn child and the wives were used to do it before entering into their new home. The eggs, associated with the spring for centuries, with the advent of Christianity became a symbol of the rebirth not ot nature but of man himself, the resurrection of Christ subject at first sight inert as a chick comes out of the egg , Christ came out alive from his tomb. In symbolism, eggs dyed with bright colors represent the colors of spring and the sunlight. Those colored dark red are the symbol of the blood of Christ. The practice of donating eggs decorated with precious items goes far back in time and already on the books of Edward I of England is marked expenditure for 450 eggs coated with gold and decorated to give as Easter gifts. But the most famous eggs were undoubtedly those of a master goldsmith, Peter Carl Fabergé, who in 1883 received by Tsar Alexander, the Committee for the creation of a special gift for the Empress Maria. The first Fabergé egg was a platinum white enamel that opened to reveal a golden egg which in turn contended a small chick in gold and a golden miniature of the imperial crown. The Tsar were so enthusiastic that a Fabergé ordered to prepare a series of donating eggs every year.

U know why we say: “Salted Prices”?

admin — Tue, 18 Nov 2008 19:40:30 +0000

Salzburg, as you know, is the city of Mozart. But you never thought to the meaning of the name Salzburg? “Burgo” comes from the German Burg, namely fortress city, and “salis” from the Latin word that means the salt. Ie: the city of salt. In fact the whole region of Salzburg is rich in salt. Austria, a country, with no sea borders, paradoxically possessed in the past some of the richest (and profitable) deposits of sea salt. Even today, moreover, its mines are active, and also visited. But why there was so much salt in this region? The history of the Earth, you know, was a history of continuous transformation of the surface crust; over hundreds of millions of years the movement of continents have continually changed the geography, so that certain portions of sea seep to be enclosed in a puddle, with no communication with the waters. The slow evaporation deposited on the bottom the sea salt: the disappearance of all the water was this deposit, then covered with soil and other sediment. That’s what happened in the region of Salzburg. Owning the salt in the past, was equal on saying he a wealth. It was considered white gold. Obviously there were no refrigerators and storage of foods, especially meat, was entrusted to salt (just think about the role that it still have in “salami”). Salt also was an essential element in the diet and to give flavor to food. Who had a salt mine, and who traded in salt, became rich. The sale today is produced industrially, but his great honor of the past have been some significant words in our dictionary: as a “salary”, “salted price”