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What are the roles of ribosomes?

The act of protein synthesis, initiated and completed by ribosomes, requires several key catalysts and actors, including the fundamental agent called mRNA. Ribosomes launch the protein synthesis process by translating mRNA into specific amino acid chains. These chains consist of two subunits, which are comprised of a third and abundant variety of RNA called ribosomal RNA. The two subunits contain over 80 kinds of specific proteins, which are lined up and assembled into sequence labels. The labels qualify as active sites, which means that they are hotspots for protein translation; each site hel..

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How do you see planets in the night sky?

A gazer who knows where to look can easily pinpoint the five brightest planets with the naked eye: Mercury, Venus, Mars, Jupiter and Saturn. The planets can be seen for most of the year, except for short intervals when they are too close to the sun to observe. However, not all the planets are usually visible at the same time. It's possible to tell planets from stars because they shift their position against stars in the background, and their brightness changes at predictable intervals over a period of time. While stars appear to twinkle, which is a result of turbulence in the Earth’s at..

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What causes the Earth's magnetic fields?

The Earth's magnetic field resembles that of a bar magnet, with north and south poles and magnetic field lines that radiate from one pole to another. Although it is believed that the Earth's magnetism originates from circulating electrical currents in the planet's molten core, this part of the planet is incredibly hot; in fact, too hot to itself be magnetic. The Earth's rotation on its axis is also related to the planet's magnetic field, a theory that scientists link to the fact that Venus lacks a measurable magnetic field but has a molten iron core similar to that of ..

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What did Galileo do?

One of Galileo's first inventions was the ancestor of the thermometer named the thermoscope. When he wrote a book on his invention of a hydrostatic balance, he gained the notice of the scientific world. Galileo went on to write the book "On Motion," in which he stipulates that in a vacuum, objects fall with equal momentum regardless of density. He went on to invent and patent a pump model, and then invented the telescope.\nUsing his telescope, Galileo identified four of Jupiter's moons, noticed sunspots and watched a supernova. Based on his observations, he validated the Copernican c..

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What was the Beadle and Tatum experiment?

Beadle and Tatum irradiated the mold to produce genetic mutations. The bread mold that they used for their experiment, Neurospora crassa, only has a single set of chromosomes. That simplified the process of seeing the genetic changes at work. Normally, Neurospora crassa only needs sugar, biotin and inorganic salts to grow, but some of the mutated strains needed arginine. Beadle and Tatum developed four strains that needed arginine, an amino acid that the unmutated strains could produce for themselves. This demonstrated that the radiation damage had affected a specific gene, which made an enzym..

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What side of the body is the pancreas located on?

The pancreas, a small C-shaped gland, plays a key role in food digestion, as it makes certain enzymes that help breakdown food. It also makes hormones, such as insulin and glucagon, that regulate blood sugar. Diseases of the pancreas include cancer, diabetes and pancreatitis. The location of the pancreas makes detection of diseases such as cancer particularly difficult until problems arise with digestion.

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What are some ways to save the Earth?

Water conservation in the home includes turning off the water when brushing teeth, fixing small leaks and having showers instead of baths. Reducing greenhouse gas emissions can be accomplished by leaving the car at home for at least two days a week, combining all errands into one trip, riding a bike or walking more and using a carpool or mass transit to get to work or school. If driving is essential, tires that are properly inflated reduce pollution, increase fuel economy and lower greenhouse gas emissions. Driving steadily with no sudden braking also saves gas.\nRecycling and using products w..

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How do you convert 83 degrees Fahrenheit to Celsius?

Subtract 32 from the degrees FahrenheitThe first step is to subtract the number 32 from the number of degrees Fahrenheit. 83 minus 32 equals 51.Multiply the value by five-ninthsThe resulting value from step one should be multiplied by the fraction five-ninths. Five-ninths is equal to the repeating decimal 0.5555. 51 times 0.5555 equals 28.3.Place the units after the resulting numberThe final step is to place the correct unit behind the resulting number. 83 degrees Fahrenheit equals 28.3 degrees Celsius.

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How is the structure of yeast hyphae different from that of mold?

Fungi are advanced microorganisms that have evolved complex means of reproduction. They can be divided into two categories based on how they reproduce: yeasts and hyphae. Hyphae fungi are called such due to the hyphal tubular filaments they send out. They are multicellular and can reproduce either asexually or sexually. The hyphae grow outwards at the tips and are divided into cells by internal walls called septa. The growing hyphae sense reproductive units and reach toward them to continue propagation. A network or colony of these hyphal filaments is called mycelium or mold.\nYeasts are unice..

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How much does an artificial knee weigh?

The selection of an implant size depends on the body's size, type and special needs. The implant is made of titanium or cobalt-chromium-based alloys and plastic parts. Any material to be used in the construction of an artificial knee must be biocompatible so that it’s not rejected in the body. Parts meant to replace knee components must be equally strong to support weight-bearing loads and absorb stress without breaking. In their designs, an artificial knee's movable parts should support frictionless motion.

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