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What is a hilar mass?

The size and definition of the mass helps determine if it is the primary tumor, the product of metastasis or the result of a non-cancerous enlargement of the lymph node. Inflammatory diseases such as tuberculosis and histoplasmosis can result in the enlargement of hilar lymph nodes. A CT scan is the best course for discovering the presence of a hilar mass and determining its cause.

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What is the difference between hail and snow?

There are seven types of snow crystals, which are all distinct from the three forms of particle precipitation, which include graupel, hail and sleet. Hail usually forms when convective clouds with strong updrafts are present. As a result, hail often occurs alongside thunderstorms. The ice pellets that characterize sleet often resemble hailstones, but they are of a smaller size, usually less than 0.2 inches in diameter.\nThe ice crystals that are characteristic of snow do not form directly from water vapor unless the temperature is below minus 40 degrees Celsius. At temperatures above minus 40 ..

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Is benzoic acid polar or nonpolar?

Benzoic acid is a colorless crystalline solid with a chemical formula of C6H5COOH. In most cases, polar compounds are soluble in polar solvents like water, but benzoic acid is a unique exception. Because of its large, hydrophobic benzene ring, benzoic acid is only slightly soluble in water when heated. Benzoic acid can be made soluble, however, by reacting it with sodium hydroxide to produce a water-soluble salt by way of hydrolysis. Benzoates, the salt products of benzoic acids, act as food preservatives by inhibiting the growth of molds, yeasts and bacteria. Benzoic acid is relatively non-to..

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What is the function of the tapetum lucidum?

The tapetum lucidum has the opposite effect of photoreceptors. These equally important organelles reduce brightness, providing night vision in nocturnal animals. Typically light hits photoreceptors from direct sources, but tapeta bounce light back towards the source, ultimately preventing absorption. This structure appears in some primates, raccoons, opossums, dogs, cats, foxes, horses and even some fish. The tapetum lucidum appears in photographs as a bright light within the animals' eyes. Like the animals in which they reside, the tapetum lucidum organelles come in various shapes, sizes..

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Why can we see other planets from Earth?

Uranus and Neptune could not be seen from Earth until the invention of stronger telescopes in the late 18th century. Some planets outside of the solar system can only be seen by the shadows they cast on their suns when their orbit brings them directly between the Earth and the star they orbit. While scientists can use other calculations, such as the Doppler method, to discover the existence of additional planets, the light from them is too dim to be seen from the Earth.

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What are the four steps in cellular respiration?

Glycolysis occurs in the cytoplasm, and it allows one glucose molecule to split into two molecules of pyruvic acid. Next, the transition reaction moves the pyruvic acid into the mitochondria, where it is converted into acetyl coenzyme A. Next, the Krebs Cycle occurs in the mitochondria and produces four molecules of ammonium triphosphate and numerous molecules of reduced nicotinamide adenine dinucleotide. Finally, the electron transport chain in the mitochondria produces approximately 32 molecules of ATP and finishes the process of cellular respiration. In total, approximately 38 molecules of ..

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Why do different pigments have different Rf values?

Rf value is a ratio of the distance travelled on chromatography paper by a pigment (considered the solute), and the distance travelled by the solvent. In other words, Rf = (distance moved by solute) / (distance moved by solvent).\nIn chromatography, a mixture of pigments to be measured is applied close to the bottom of a strip of chromatography paper. This strip of paper is then placed in solvent, so that only the bottom edge of the paper touches the solvent. Because of the paper's capillary action, the solvent moves up the chromatography paper, and as it crosses the area where the pigmen..

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What does 10 millimeters equal in inches?

If converting from millimeters to inches, multiply millimeters by .03937. It will provide a rough estimate of how many inches the millimeters would equal. To convert inches to millimeters, multiply inches by 25.4. This will provide the equivalent number in millimeters.Millimeters are a unit of measurement in the metric system. Millimeters are the smallest metric unit of measure. There are 10 millimeters in one centimeter. Other metric system measurements include centimeters and meters. Millimeters may be used when someone needs a very precise measurement of something, such as in architecture o..

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What is the difference between cytoplasm and protoplasm?

Protoplasm is a word that has been phased out of use in modern biology due to its largely inaccurate origin. Nowadays, it refers only to the cytoplasm and the nucleus instead of implying that cells were only containers of protoplasm. Modern science has since discovered that cells are much more complex.\nCytoplasm is the substance that contains the organelles of cells that have a nucleus, surrounding the organelles like the mitochondria, the Golgi apparatus and the cytoskeleton. These components are all a part of a cell in the same way as large organisms have organs, performing vital functions ..

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What are glandular tissues?

The University of Leeds Histology Guide states that endocrine glands include the adrenal glands, thyroid, thymus and pituitary glands. Secretions made by these glands pass directly into the bloodstream. Exocrine secretions, such as those produced by the sweat, salivary and mammary glands, pass through ducts to reach their final destination.\nExocrine glandular tissue produces one of three secretion types. Sebaceous tissue produces sebum, a white, oily substance that lubricates the skin and traps moisture beneath its surface. The ducts through which sebum passes are called pores. Mucous tissues..

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