food

from Wikipedia, the free encyclopedia

Food is made up of various substances and is the basis for metabolism and thus for life. In heterotrophs (mostly animals), food contains energy-rich organic compounds. In autotrophs (mostly plants) is also called nutrients - they do not contain any high-energy organic substances. Components of food for humans such as B. Bread , meat and sausage products , vegetables , fruit or cereals are referred to as food .

In animals with a digestive tract, food is usually broken down mechanically (e.g. by chewing ) and chemically (e.g. by gastric acid ) after it has been absorbed into the body . The energy stored in certain food components is used in the energy metabolism to z. B. to keep the body temperature constant in warm-blooded animals . Furthermore, the energy from food is used in the anabolic metabolism ( anabolism or building metabolism ) to maintain and build up the body (e.g. growth in children or muscle building in adults).

Water and salts are also part of food, even if they cannot be used directly in the energy metabolism. Food includes vitamins , which are essential compounds that some species cannot synthesize themselves. The lack of food is known as hunger and can lead to the death of a living being ( starvation ).

Food supply

The food supply describes the availability of appropriate food that the respective organism needs. Food is often a limiting factor and, if there is an oversupply for living beings with a high reproductive rate, usually results in an explosive increase.

The best example is brewer's yeast , which is used for brewing beer. The wort represents the nutrient medium in which the mushrooms multiply exponentially. Until they perish on their own metabolic products, ethanol , and suddenly die off. This can be observed in bacterial cultures.

In the animal kingdom, such as B. in mammals , the supply has a regulating effect on the population development of individual animal species . This means that as a carnivore's food supply increases , its population gradually increases. This increases the pressure on the population of the prey, the population of which is shrinking again and thus delayed, including that of the hunter. In order to understand the fluctuations in population numbers caused by the predator-prey relationship , the most important relationships have been summarized in the Lotka-Volterra rules .

Since humans are at the top of the food chain , they intervene most massively in the equilibrium of nature. The synthetic production of fertilizers and pesticides ( Haber-Bosch process ) enables a world population of approx. 7 billion people. Another important factor in food security is conservation . Since humans are at the end of the food chain, they are most at risk from pollution. That is why people are often warned against consuming sea fish, as they particularly accumulate the pollutants of the sea in their bodies.

Microorganisms close the food chain by decomposing dead plants and animals and thus providing food for plants again. But you can also expand the food supply of other living beings, such as B. yogurt or cheese cultures. Or they harm other organisms, such as B. Pathogens that feed on tissue and blood cells. You thus ensure natural selection.

Other uses of the term

With the term "spiritual food" often challenges paraphrased for thinking, for example, Puzzle tasks or "reading material" , as "food for the soul", however, the transfer of emotions and the psyche flattering human reactions such recognition , acceptance , attention , acknowledgment , Care , praise , compliments , respect , understanding and appreciation .

See also

Portal: Eating and Drinking  - Overview of Wikipedia content on the subject of Eating and Drinking

literature

  • Utz Thimm, Karl-Heinz Wellmann: On everyone's lips. Diet today. Suhrkamp Verlag (stw 3602), Frankfurt am Main 2004, ISBN 3-518-45602-4 .
  • Utz Thimm, Karl-Heinz Wellmann: Eating is human. On the food culture of the present. Suhrkamp Verlag (stw 3533), Frankfurt am Main 2003, ISBN 3-518-45533-8 .
  • Andreas Hahn, Alexander Ströhle, Maike Wolters: Nutrition. Wissenschaftliche Verlagsgesellschaft mbH, 2005, ISBN 3-8047-2092-7 .

Web links

Commons : Food  - album with pictures, videos and audio files
Wikiquote: Food  - Quotes
Wiktionary: Food  - explanations of meanings, word origins, synonyms, translations

Individual evidence

  1. ↑ Arnold Arni (ed.): General, inorganic and organic chemistry for subject teaching and self-study . 3. Edition. Wiley-VCH, 2010, ISBN 978-3-527-33068-3 .
  2. ^ Warning of mercury in food fish , Süddeutsche Zeitung, May 22, 2010.