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Is lead a metal or nonmetal element?

Lead is a very dense yet soft and malleable metal that possesses corrosion-resistant properties. The existence of lead has been recognized since ancient times, and it is occasionally found in nature. It is mainly found in ores such as minum, galena, cerussite, and anglesite. Lead is used to protect cables and wires from corrosion and to store corrosive liquids, among other uses.

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What are cinara aphids?

Cinara aphids are dark in color and can be various shades of brown and black. This genus features some of the largest aphids in the world and can be found anywhere conifers grow. Their common hosts include spruces, pines, true firs and Douglas fir trees. Large populations of aphids can cause significant damage and even death to some conifers. Interestingly, aphids cause no damage at all to some trees, such as the Fraser fir.

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How many satellites does Mercury have?

Messenger’s mission to Mercury was launched on August 3, 2004 and began an orbit of Mercury in March 2011. In the 1970s, astronomers believed Mercury might have a moon based on large amounts of ultraviolet radiation detected by a National Aeronautics and Space Administration (NASA) spacecraft. It was later determined that the radiation was coming from a distant star, rather than a moon. As of 2014, no moons, rings or signs of life have been seen on Mercury, according to NASA.

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What is a PCR cycle?

The first step of the cycle is denaturation. This step heats and separates the strands of DNA. The second step is annealing. This step is used to attach primers and polymerase to strands of DNA. The third step is elongation. This step continuously adds a base after each primer to completely synthesize a new DNA strand. The steps in this cycle are repeated up to 35 times to produce a large quantity of DNA samples. Although there is an initialization step before denaturation and a final elongation step after elongation, these steps are not repeated during the cycle.

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What are some of the world's most endangered species?

The estimated numbers remaining in each of these critically endangered species vary; scientists estimate that only 60 Amur leopards survive, while several hundred animals of the other species remain. Scientists have mounted efforts to breed and protect endangered species, and the World Wildlife Fund keeps an online, updated list of the most critically endangered animals worldwide.

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What body part doesn't grow?

Attached to the eardrum, these tiny bones work together to transmit vibrations from sound waves to the fluid in the inner ear. They are found in the middle ears of all mammals. These bones, named after the objects they resemble, are the malleus, or hammer, the incus, or anvil, and the stapes, or stirrup.\nA common misconception is that the eyes do not grow from infancy. However, the human eye grows about one-third in size. At birth, the eyeball is 16 millimeters wide, but it grows to 23 millimeters in width by the age of 3 years. Eyes reach their maximum size at puberty, growing to be approxim..

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What is the chemical structure of acetylsalicylic acid?

Acetylsalicylic acid is commonly referred to as aspirin. It is part of a group of drugs known as nonsteroidal anti-inflammatory drugs, or NSAIDs, which are used to suppress inflammation. It's used to treat aches in the muscles and joints as well as headaches. It is also effective at reducing fever and treating rheumatoid arthritis.

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What is the chemical formula for wheat flour?

Wheat flour is typically used for consumption purposes; however, the thickening ability of the starch has caused it to be added into many other various compounds, like in making paste.Starch is not fermentable; however, it can be easily detected by adding free iodine into the system. If the solution turns blue, it is an indication that starch is present. The starch in wheat flour is typically broken down by the body into dextrin and maltose by an enzyme known as diastase. The chemical structure of starch can also be broken down if it is heated up.Whole-wheat flour is typically derived from the..

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What animals live in the emergent layer?

Harpy eagles, named after the harpies of Greek mythology, typically live in the rainforests of Central and South America, although the destruction of their habitat has caused many of them to move to Panama. The birds weigh approximately 20 pounds and are distinguished by their mottled coloring, 7-foot wing span and large feet, which are roughly the same size as an adult human male's. Their coloring allows them to blend in with the bark of the surrounding trees, making it easy for them to capture prey, such as sloths and monkeys, in both the emergent layer and the forest canopy.\nSparrowha..

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What is the Michaelis-Menten constant?

The equation relates reaction velocity to the concentration of the substrate. Maximum velocity is reached when the substrate is at a saturated concentration. This equation only works for reactions where the substrate initially creates a reversible bond with an enzyme and makes a enzyme-substrate complex. By using up the substrate, this complex creates a product. The enzyme is released and can bind with another substrate to reproduce the entire reaction. In 1925, George Briggs and J.B.S. Haldane gave a simple derivation of the equation that is still used today.

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