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Why are wetlands being destroyed?

Wetlands are a type of ecosystem characterized by either a seasonal or permanent saturation of land by water, which can either be fresh, brackish or salt. Aquatic plants and other vegetation specific to wetlands are another defining characteristic, as they are fully adapted to the exclusive hydric soil. Wetlands are useful to the environment due to their ability to purify water, provide stability to shorelines, serve as a home for a variety species and act as a buffer for floods. Examples of wetlands include swamps, bogs, marshes and fens. Climate varies based on location, but wetlands are pre..

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What is the current model of an atom called?

Whereas the Bohr model sees atoms being orbited by electrons, the Quantum Mechanical or Electron Cloud model explains that the atomic nucleus is surrounded by probability "clouds" of electrons called orbital. This is a better representation of the actual quantum physics of atomic structure.

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Why do things fall?

In addition to gravity, mass plays a role in the speed at which an object falls. Aristotle was the first to note that two objects fall at the same rate regardless of size because gravity is a stronger force than acceleration due to mass. The force of gravity occurs to different degrees on other planets and throughout the solar system. The moon orbits the Earth because of gravity.

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What are metals made from?

Metals such as platinum, gold, copper and silver are found in pure forms, while alloys, such as bronze and brass are made by heating two different kinds of metal together and then allowing the mixture to cool. For example, copper and tin are mixed to create bronze, and copper and zinc are used to make brass. By definition, an alloy is a solid material that is made from the mixing of two or more metals. Metals are naturally hard and can be shiny, rough or dull in appearance.

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What happens to pyruvic acid before it enters the citric acid cycle?

The conversion of pyruvic acid to acetyl coenzyme A is known as the oxidative decarboxylation of pyruvic acid. This reaction involves NAD+ removing two hydrogen molecules and two electrons from pyruvic acid. The result is acetyl coenzyme A, NADH, H+ and CO2. These products go into the citric acid cycle to produce more CO2 and ATP. The citric acid cycle is also known as the Kreb’s cycle and the TCA cycle.

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Under what conditions can potassium bromide conduct electricity?

Potassium bromide in its solid form contains ions, which are charged atoms. However, the ions are bound so tightly in the solid form of potassium bromide that electricity cannot flow between them. Once it is melted, though the ions are free to move and electricity can be passed between them. Through the heating process, the melted potassium bromide becomes an ionic liquid. If solid potassium bromide is dissolved, for example in water, the resulting release of ions allows it to conduct electricity.

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What is the function of teeth?

The permanent dentition begins at the midline, and it consists of incisors, canines, premolars and molars. The primary dentition has the same components, but it doesn’t have premolars. The eight front teeth are called incisors, and they allow a person to bite and cut food. Incisors slice food with their sharp ends. The part of the teeth that people use to tear food are known as canines, which are the sharpest type of teeth. Canines are also capable of grasping and retaining food.\nPremolars are located at the back of the canines, and they are designed to hold, chew and grind food. Humans hav..

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What is 150 milliliters in fluid ounces?

A fluid ounce is a form of measurement that is commonly used in U.S. and British measuring systems. An ounce is equal to 30 milliliters and a fluid ounce is used only to measure liquids. Throughout history, there have been many definitions of an ounce. It was primarily used in England and in Scotland to measure both wine and water. When it was used to measure these things, the measurement of the ounce varied depending on the liquid that was being measured. For example, an ounce of ale would be a different amount of liquid than an ounce of wine.The fluid ounce that is used in the U.S. is somewh..

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What household items contain minerals?

Wall clocks contain the minerals pentlandite and quartz, used in the spring and the time-keeping element of the clock, respectively. Safety matches contain sulfur and stibnite. Kitchen stoves contain the minerals hematite, chromite, galena, copper and cinnabar. Paper is often made with clays containing mica, talc and barite to roughen the surface, and is colored white using pigments made from rulite and ilmenite.\nPencils are often mistakenly thought to contain lead, but, in fact, contain the mineral graphite. Graphite is a soft and malleable allotrope of carbon, so it is mixed with clay to ha..

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What is a rotary cuff?

The muscles and tendons that comprise the rotator cuff allow for a wide range of motion while still providing stability to the joint. The head of the humerus articulates with a shallow groove of the shoulder blade called the acromium process. This joint is unstable and needs the rotator cuff, along with the capsular ligament surrounding the joint, to remain in articulation. This delicate balance between stability and range of motion is the reason why the rotator cuff is easily injured.

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