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Why is chlorophyll green?

Green plants appear green because of the amount of chlorophyll present; as the days shorten, the amount of chlorophyll reduces. As this happens, the other pigments in the leaves show, making the leaves appear to change color. Chlorophyll is added to certain foods and beverages to make them green. Since it is not water soluble, it must first be added to vegetable oil in order to be used.

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How is a cell like a city?

The outer membrane of a cell, much like a city wall, surrounds the cell and creates a boundary between it and another cell. Fatty molecules, called lipids, form this thin and flexible membrane, which creates a strong cellular cover.\nA cell's cytoskeleton consists of several networks of micro-filaments, intermediate filaments and microtubules. This system defines the center of the cell and distinguishes one end of the cell from the other end. Cell components move along this network, which is made up of water, ions, molecules and proteins, much like cars along a highway. This network can p..

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What is radar used for?

Aircraft employ radar as a means of warning against obstacles and other aircraft that are on their flight path. Additionally, radar determines the aircraft's altitude with great precision. Similar to aircraft, naval vessels use radar to identify the bearing and distance of other ships, in addition to using it to navigate and determine their position relative to the nearest shore or other fixed points of reference, such as islands or buoys.\nRadar is also employed for military-related purposes, such as target-acquisition systems that are used in various missile types, including air-to-air,..

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How do ocean currents influence climate?

The size, depth and location plays a key role in determining the effect of currents. Shorter horizontal currents, or riptides, exchange cooler, deeper ocean water with warmer water on the surface. This exchange modifies the ocean water temperature. It also influences surrounding air temperature through the processes of downwelling and upwelling. Downwelling occurs when currents bring large volumes of cold water to the surface. This water combines with strong northern and western winds, cooling the air. Similarly, currents bringing primarily warm water to the surface, called upwelling, elevate ..

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How is carbon stored in the biosphere?

Carbon stored in the biosphere gets there through photosynthesis in green plants. The process of photosynthesis includes removing carbon dioxide from the atmosphere. After producing their food, plants release oxygen back into the air.\nAnimals receive carbon when they eat plants and then release carbon dioxide into the atmosphere upon exhalation. When animals and plants die, their carbon turns to fossil fuels after millions of years in the form of coal, oil and natural gas. The burning of these hydrocarbons in power plants and automobiles releases more carbon into the air and contributes to gl..

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What is 250 grams in litres?

Since grams and liters are both metric units of measurement, they have a base of 10, which means that converting grams to liters simply requires a person to divide 1,000 by the amount of grams. A person could also just move the decimal point three places to the left. Likewise, converting liters to grams involves multiplying by 1,000 or moving the decimal point three places to the right.

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How many centimeters are in a meter stick?

The word centimeter, which comes from the late 18th-century French word "centimetre," is derived from the Latin root "centum," meaning "hundred" and the Greek root "metron," meaning "measure." The meter became the standard measurement of length for the metric system, adopted first in France in the middle of the 19th century, then in many parts of the world in the later part of that century. The prefix "centi-," like others, was adopted to describe decimally smaller increments of a meter.

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What is the laboratory interpretation of yeast cells in the stool?

High levels of yeast in the stool may be associated with inflammatory conditions, argues Carol A. Kumamoto in a review article published in Current Opinion in Microbiology. Kumamoto's opinion is based on the fact many patients suffering from gastrointestinal diseases such as Crohn's disease may have increased yeast in the stool. The author notes however that since many of these patients receive regular treatment with antibiotics, the level of yeast in the stool may be a side effect of the antibiotics.\nStool is tested for pathogenic organisms in cases of diarrhea that continue for se..

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How did the periodic table get its name?

All the elements that belong to a period contain the same number of atomic orbitals. Going down the periodic table, the number of atomic orbitals increases by one for each row. The topmost elements have one orbital for their electrons, while those at the very bottom have seven orbitals for their electrons. For the groups, elements under the same category contain the same number of electrons in their outer orbitals; these outer electrons are called valence electrons.

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What is a HAZMAT practice test?

To qualify for a HAZMAT endorsement, the applicant must pass the HAZMAT test, an FBI fingerprint check and a background check. The applicant must also provide proof of identity to the Transportation Security Administration.Taking a HAZMAT practice test gives applicants the opportunity to test their skills prior to taking the real exam. If applicants miss questions on the practice test, they can study those areas more thoroughly prior to taking the actual test.Websites like Truckers Country offer free HAZMAT practice tests for people who are applying for a HAZMAT endorsement for the first time ..

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