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What are minerals that contain silicon and oxygen called?

Some of these different silicate minerals are feldspar, quartz, micas, olivine, pyroxene and amphibole. These silicates have different chemical formulas. For example, while quartz has the chemical formula SiO2, the olivine group has the general formula (Mg,Fe)SiO4. Similarly, the cleavage of silicates is determined by their individual crystal structures. For example, feldspar has two cleavages at right angles, while quartz has none. Cleavage is a mineral's tendency to break along a planar surface.

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What is an allosteric effector?

The presence of an allosteric effector can change the affinity of the enzyme for its substrate, or alter the maximal catalytic activity of the enzyme, or both. Allosteric effectors can bind to regulatory proteins involved in RNA transcription altering its activity. During this process, activator proteins become active in order to bind to the DNA, which promotes RNA polymerase and inactivates repressor proteins. RNA polymerase can then bind to the DNA.

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What is endosperm?

Encyclopedia Britanica states that the induction of endosperm necessitates the bond of at least one nucleus in the embryo sac with a sperm nucleus from the pollen grain. The process of endosperm varies from types of angiosperms. For example, in seeds such as peas and beans, the endosperm is completely absorbed at maturity. In others, such as wheat, the endosperm is apparent until germination. It is noted that endosperm accounts for the economic importance of cereal grains and oil seeds.\nPlantCell confirms the notion that endosperm represents a vital source of food, feed and industrial raw mat..

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What side is your spleen on?

There can be different medical conditions, such as liver disease and mononucleosis, that can cause splenomegaly, or an enlarged spleen. Some other health problems that can affect the spleen are low platelet counts and an injury that causes a rupture.In some cases, people may not experience major symptoms with an enlarged spleen, and the condition is diagnosed through either a physical exam or testing. Treatment is dependent on the direct cause for the spleen condition. An enlarged spleen caused by an infection may require antibiotics.

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Why is blood considered to be a tissue?

MedlinePlus states that blood is living tissue comprising both liquid and solids. The liquid, plasma, consists of protein, salts and water, while the solids the blood contains are platelets and red and white blood cells. The majority of the blood in the human body is plasma.\nThe different components of the blood play diverse roles in the human body, according to MedlinePlus: red blood cells take oxygen from the lungs to organs and tissue, white blood cells defend the body against infection, and platelets assist with the blood clotting process when a person is wounded. The blood solids have di..

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What are living organisms that create their own food called?

Producers can range in size from large plants like trees to much smaller organisms like plankton. Some types of plankton or algae are so small they can be difficult to see with the human eye. Producers create their own food using the sun's rays in a process called photosynthesis.The energy gained from the sun's rays is paired with carbon dioxide taken from the air and water from the soil to produce the sugars that are needed to keep the plant healthy and alive. In turn, these organisms create oxygen for the other organisms in their ecosystem.These organisms are generally consumers or..

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What is the density of salt water?

One easy way to demonstrate the difference in density between salt and fresh water involves placing salt water on the bottom half of a glass. The top half of the glass is then filled with fresh water. When an egg is lowered into this water, it sinks through the fresh water and floats in the middle of the glass. This is because it is easier for objects to float on top of denser water.

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What are standard enthalpies of formation?

The standard enthalpy of formation is calculated by subtracting the sum of the standard enthalpies of the reactants from the sum of the standard enthalpies of the products in a chemical equation. Enthalpies are listed as joules or kilojoules of energy. One mole is 6.22 x 10^23 atoms of a particular substance. For example, one mole of carbon is 12 grams as indicated by carbon's atomic mass of 12.\nThe standard enthalpy of formation for pure elements in their normal state is zero. Some standard enthalpies of formation for certain substances include 33.18 kJ/mol for nitrogen dioxide, -296.8 ..

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How big is a plant cell?

While size of plant and animal cells differ greatly, both cells are extremely similar in many ways. The major differences are what the cells use for energy and how energy is produced. Plant cells use the sun for energy, which is converted to energy through photosynthesis. Animal cells rely on food for energy, which is converted by the mitochondria of the cell.

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What happens when snow melts?

Snow melting relies heavily on air temperature and the intensity of the sun. Other factors are also important to a lesser extent, like the speed and temperature of the wind and whether it is raining. The terrain on which the snow has fallen and its angle to the sun is also fundamental.\nWhen the temperature begins to rise and the heat from the sun reaches the snow, the melting process begins. Because the top layer of snow is the first to receive this energy from the sun, snow melts from top to bottom. The energy in the heat turns the snow into water by breaking down the snow crystals. When the..

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