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What has a cell wall composed of cellulose?

Plant cell walls appear as little boxes that are given their shape by two chemicals: cellulose and lignin. The cellulose is tough and flexible with the lignin acting as a sort of "glue" holding the cellulose together. Because of the nature of the cellulose and lignin "team," plants can grow into tall trees, flexible grass or anything in between. Cellulose and its derivatives are found in many manufactured products, from paper to plastics and even money itself.

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What are some facts about Planet X?

The WISE project was in operation between 2010 and 2011, with a brief hiatus. During that time it studied more than 750,000,000 asteroids, stars, galaxies and other bodies. About 762 of these objects had never been seen before. Another study discovered 3,525 brown dwarfs and stars, but none of them were in the solar system. Some very close stars included a binary system of two brown dwarfs that were 6.5 light years from Earth. Though this is close in astronomical terms, it is very far out of the solar system. It takes whatever light these brown dwarf stars emit 6.5 years to reach Earth.\nThe e..

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What is the chemical reaction for fermentation?

The result is ethanol and is expressed as chemical formula C2H5OH.\nAlcohol fermentation is a common process used to produce bread, beers, wines and ethanol-based fuels. Also known as ethanol fermentation, it is a metabolic anaerobic process where yeast, a micro-organism, converts carbohydrates, such as simple sugars, into ethanol and carbon dioxide.

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How is calcium phosphate made?

Calcium phosphate can also be obtained directly from mineral sources, but this is rarely done. The minerals oxydapatit, voelicherite and whitlockite contain natural calcium phosphate.\nCalcium phosphate is used as a nutritional supplement for both humans and livestock, fertilizer, food additive, medicine and contrast agent. It occurs naturally in the milk and blood of cows. Human bones are composed of 70 percent calcium phosphate, and human teeth consist of 90 percent calcium phosphate. Calcium phosphate is less popular as a supplement than its lower-cost alternatives calcium carbonate and cal..

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How tall is 170 centimeters?

Each centimeter equals a hundredth of a meter. To convert centimeters to meters, the number of centimeters is divided by 100. There are 2.54 centimeters in an inch, so dividing the number of centimeters by 2.54 converts the centimeters to inches. There are 12 inches per foot, so dividing the result from the centimeter-to-inch conversion by 12 provides the total feet and inches.

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What carries blood from arterioles into venules?

Capillaries have a key function in microcirculation, which involves the circulation of blood within the body, starting at the heart. Blood pumped from the heart travels through the arteries, arterioles, capillaries, venules and veins, and then it travels back to the heart. These tiny blood vessels measure less than 10 microns in diameter and are useful for exchanging waste between blood and tissue.

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How many grains equal a milligram?

The grain is conceptually defined as the weight of one grain of barley. Modern uses of the grain unit include the measurement of:\n\nBullets\nGunpowder\nGold for dental use\nHardness of water (in the U.S. only)\nParticulate emissions levels\nHumidity\nMedications\n\n

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How do sound waves transfer energy?

Waves can be characterized by two basic parameters: amplitude and frequency. Focusing on a single point vibrating in a medium excited by a sound wave, amplitude is the maximum distance traveled by the vibrating point relative to its rest position. Taking a snapshot of a propagating sound wave at any instance shows consecutive compressions and rarefactions, regions in which the medium material is compressed together and spread widely apart, respectively. The distance between the centers of two successive compressions or rarefactions is the wavelength of the wave.\nThe frequency is the inverse o..

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What do evolutionists believe?

Darwin's view of evolution heavily favors natural selection — or "survival of the fittest." Natural selection favors genetic variations that will most likely give the species the best advantage at surviving.\nEvolutionists are often divided into two groups: punctualists and gradualists. Punctualists believe life developed sporadically in short bursts as a result of environmental changes. In contrast, gradualists believe life developed slowly and gradually, over longer periods of time.\nDarwin's theory of evolution belongs to the gradualist camp. He believed evolution to be a slow, ..

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How does pressure affect the states of matter?

This occurs because the state of matter depends on how quickly its molecules are moving, or how much energy they have. At high pressures, the molecules cannot move as quickly because they are packed more densely. The closer molecules are, the tighter of a bond they form. More energy is necessary to make them break the lattices that make a solid structure. Pressure can be exerted on gases more easily than on liquids and solids.\nA pressure cooker makes use of this property of matter. By increasing the pressure inside the cooker, it increases the temperature at which water boils. Hotter liquid w..

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