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What are the functions of collagen and elastin?

Collagen is commonly found in connective tissue, but can also be found in the body's cartilage, bone, blood vessels and even the gastrointestinal tract. Collagen fibers help support tissues as well as the extracellular cellular matrices.In each of the locations within the body, collagen works with other proteins like keratin and elastin to add flexibility and waterproof capabilities to the parts of the vertebrae. When a person loses collagen in their body, they begin to develop wrinkles.The elasticity of tissues, including the skin, is due to elastin. Because of elastin's elastic pro..

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Who is Jacques Piccard?

While the Challenger Deep mission was an impressive achievement, it ultimately proved to be an expensive and relatively useless one. The Trieste carried no scientific equipment and was not capable of taking pictures. Piccard made the trip simply to determine whether humans could reach the bottom of the trench. While the vessel descended and returned safely, the windows began to crack under the extreme pressure. Piccard called a halt to their stay on the bottom after only 20 minutes, and began the return to the surface.\nLater in his career, Piccard took part in a six-man survey of the ocean fl..

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What muscle tissue allows you to move your eyeballs?

Contraction of the lateral rectus causes the pupil to look outwards, while the medial rectus turns the eyeball inwards. The inferior rectus focuses the eyeball downwards, whereas the superior rectus pulls the eyeball upwards. The inferior and superior oblique muscles are attached to the eye at an angle and aid in rotating the eyeball.

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Why is coal not a mineral?

According to the World Coal Organization, the chemical composition of coal includes carbon, sulfur, hydrogen, oxygen and nitrogen. The proportion of these and other elements in a coal vein depends on its location, age and the types of organic material that contributed to its formation.\nThe term "coal" refers to seven related substances. The deeper the coal is, the higher its quality. Peat is a popular fuel in certain European countries and has powerful absorptive ability. In that context peat is quite useful during oil spill cleanup. Lignite has a medium brown color and is only used to power ..

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What is the chemical formula of polyurethane?

Polyurethane is used in many common everyday items. Car seats are polyurethane cushions surrounded by a fabric or leather cover. Chair or seat cushion polyurethane foam is dense and sturdy, but it can be made to be as soft and supple as in a bed pillow. Carpet padding can be polyurethane as well, which is made into thin layers.\n\nWhen making foam cushions, polyurethane starts out as a liquid that is easily poured into molds. The molds are fashioned into whatever custom shape is needed for a particular item.

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What animal weighs a ton?

Of these very large animals, the blue whale is by far the heaviest, tipping the scale at an astounding 110 to 176 tons. For comparison, the second heaviest is the African elephant, weighing in at 4.5 to 7.8 tons. It takes up to 40 African elephants to weigh as much as a single blue whale.

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Why does light refract?

The theory of relativity imposes a maximum speed on light, but there is no restriction on how much it can be slowed as it passes through a medium. As light of diverse wavelengths enters a slow medium, the different wavelengths of light react to the change in medium by slowing at different rates. This bends the light, sometimes dramatically.\nWhen refraction is done in a prism, whether natural or artificial, the result of this differential bending is that white sunlight gets spread out into its constituent colors. Each color is just a wavelength of light, and each can be isolated from the other..

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What are some examples of decomposers?

Decomposers are known as heterotrophs because they eat organic substrates to obtain carbon, energy and other nutrients to grow and thrive. Decomposers break down the organic substrates via biochemical reactions that convert the substrates into metabolically useful products. This removes the need for internal digestive organs in decomposers. For this reason, most decomposers are bacteria and fungi. Bacteria are widespread and can break down a myriad of organic matter. Typically 1 gram of soil contains around 40 million bacterial cells that can break down organic molecules in the soil, which in ..

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How do you convert lumens to watts?

A light's lumens per watt value is generally specified by its manufacturer. If you know the brand and type of light, the specifications can be obtained from the manufacturer, which often lists such information on its website. If these values cannot be obtained from the documentation, you can, conceivably, measure both of them. However, that requires measuring equipment, at least an electrical multimeter and light meter, and the know-how to use those tools effectively in the given situation.

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What is the function of the trileaflet aortic valve?

During systole, the valve opens allowing oxygenated blood to leave the left ventricle and enter the bloodstream, explains the University of Minnesota Department of Surgery. During diastole, the valve closes preventing backflow into the left ventricle.\nAortic stenosis and aortic regurgitation are two of the more common conditions associated with a malfunctioning aortic valve, notes Healthline. Aortic stenosis is a condition in which the valve does not fully open, leading to potential blockage. Aortic regurgitation occurs when the valve does not close properly, and some of the oxygenated blood ..

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