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What is the difference between endocrine glands and exocrine glands?

The endocrine system plays an important role in coordinating the body’s various systems. These glands accomplish this by creating and secreting hormones, which function as chemical messengers for the body. Because endocrine glands secrete hormones directly into the bloodstream, they can affect organs located far from themselves. The adrenal glands, parathyroid, thyroid and pituitary glands are examples of endocrine glands. The University of Leeds explains that the pineal gland is one other example of an endocrine gland, and it is located in the brain. The pineal gland is a photoreceptive org..

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What level of radon gas is considered high?

Exposure to radon at any level, even below the recommended action level, poses an increased risk of lung cancer. According to the U.S. Surgeon General, exposure to radon gas indoors is the second-leading cause of lung cancer in the United States. The only way to determine radon levels within a home is to perform testing. Do-it-yourself radon testing kits are available.

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What is the central vacuole of a plant cell?

Central vacuoles serve as primary water storage centers for plants, retaining much of the water plants ingest during the day. They change shape after filling with water, performing dual duties of acting as reservoirs and giving plant structures shape. Upon reaching size capacity, central vacuoles expand outward, putting pressure on the surrounding cytoplasm. This force, called the turgor pressure, makes cells tight and strong. This rigidity gives surrounding plant parts, such as leaves and stems, distinct structures. When central vacuoles lose water, the leaves and stalks shrivel and wilt.Cent..

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How often do earthquakes happen in California?

Research conducted by the U.S. Geological Survey in 2008 reported that California can expect an earthquake of 6.7 magnitude or greater once every 6.7 years. The southern portion of the San Andreas system of faults is of particular concern to geologists who feel this to be the site of the next major quake that they consider a certainty within the next 20 years.

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What phosphorylates ADP to make ATP?

To phosphorylate ADP, protons enter the ATP synthase complex from the region between the inner and outer membranes of the mitochondria. The process of protons entering the proton channel of the F0 portion of the enzyme creates energy to power the process of adding a phosphate group to ADP by the F1-ATPase portion.\nPower from protons entering the proton channel also rotates a part of the F1-ATPase called the central stalk. When the central stalk turns, a phosphate group is added to ADP and then the newly synthesized ATP molecule is released.

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How are proteins made?

Amino acids are synthesized from nutrients delivered to cells via the blood. In eukaryotic cells, they are transported to specialized organelles called the rough and smooth endoplasmic reticulum. These structures are membranes close to the nucleus that have convoluted and deeply folded surfaces, providing plenty of surface area to work on.\nLong chains of amino acids are assembled by rolling along the surfaces of these membranes, picking up additional amino acids as they go, until they reach the end of the conveyor. On release, the long-chain amino acids snap into shape as proteins. Smaller pr..

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What is the equation for conservation of momentum?

One of the most important laws of physics, the law of conservation of momentum, can also be expressed as "?m*v = constant", where "m" is mass of the objects and "v" is their respective velocity. This dictates that the net amount of momentum before and after a collision always remains the same. During collision, while one of the objects loses its momentum, the other object gains the exact same amount of momentum but in the opposite direction.\nAnother important term involved in this law is the "isolated system." Generally speaking, a system is a collection of two or more objects. An isolated sy..

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What makes up the sun?

Helium was first detected in the sun, which is why the element was called "helium," after Helios, the sun god in Greek mythology. Helium is present as a by-product of the sun's nuclear processes. The hydrogen that makes up the bulk of the sun's composition is very hot and exists in an excited phase of matter known as plasma.\nUnder less energetic conditions, hydrogen atoms encounter and repel each other in a weak fashion. In the crushing pressure and blazing heat of the sun's core, however, the hydrogen atoms aren't able to bump off each other, so they strike and stick toge..

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How much land is an acre?

Traditionally, an acre is 1 furlong long by 4 rods wide, according to Washington Grown. It developed as a standard of measurement comparable to what a yoke of oxen could plow in a single day. Including water, New York City is about 300,000 acres, including its bodies of water, while Greater London is about 388,000 acres.

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What did Alexander Fleming discover?

When he isolated penicillin, Fleming found that the substance killed bacteria but had no effect on animals. Fleming had trouble isolating and producing the substance because it was unstable. Other scientists, such as Ernst Chain and Howard Florey, were able to isolate penicillin and mass produce it for widespread use. The first antibiotic discovered, penicillin kills the dangerous bacteria that causes diseases such as diphtheria, meningitis and strep throat.

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