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Is MRNA synthesized in translation or transcription?

The synthesis of a strand of mRNA inside the nucleus of a cell is the first step to making a protein. An enzyme called RNA polymerase begins the process of transcription. The DNA unwinds and unzips, exposing a strand to serve as the template for making an mRNA strand. RNA polymerase adds bases to the growing mRNA strand one base at a time. The bases that make up RNA are adenine, guanine, cytosine and uracil. Following transcription, the RNA molecule is allowed to pass through the nuclear membrane into the cytoplasm where protein synthesis occurs. DNA is not allowed to exit the nucleus.

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When is tick season?

Because some ticks resume activity as soon as the snow melts, the ground thaws and temperatures rise above freezing, precautions should always be taken during outdoor activities. In addition to reducing exposure risks by avoiding tick-infested areas, such as the woods and overgrown vegetation, hikers should wear pants tucked into their socks, use tick repellents on their skin and clothing, and frequently check their skin, hair and equipment for ticks.

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How does weight affect speed?

Newton's first law of motion states that an object at rest stays at rest and an object in motion stays in motion, unless that object is acted upon by an unbalanced force. This force overcomes any resistive forces, such as friction, in order to cause acceleration. Acceleration causes an object to change its speed or its direction of motion.\nNewton's second law states that a force is a product of an object's mass multiplied by an object's acceleration. Weight itself is a type of force in which the acceleration on the object is due to the effect of Earth's gravity. Since..

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What is the basis of polystyrene?

While polystyrene is an extremely versatile product, its makeup causes some significant health problems. Those who work with styrene, the central building block, run the risk of irritation of the upper respiratory tract, eyes and skin, as well as negative effects in the gastrointestinal tract. Renal function and neurological health are also at risk, and styrene is on the Environmental Protection Agency's list of potential human carcinogens.\nThe risks of using polystyrene do not end when the product is manufactured. Toxic chemicals have been detected leaking out of products into the items..

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What do "ball and socket," "hinge," "pivot" and "gliding" all relate to?

A ball-and-socket joint such as that found in the hip or shoulder consists of the round head of one bone fitting into a cup-like structure on another bone. These types of joints give the most freedom of motion. Hinge joints are found in the knees and elbows, and they allow the bones to swing in only one direction. A pivot joint lies between the radius and ulna bones of the arm, allowing the end of the radius to rotate on the ulna. A gliding joint allows only limited motion and can be found between the bones of the wrist.

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What is capillarity?

Encyclopedia Britannica explains that when a thin tube is inserted in water, the water rises due to the forces of attraction between the walls of the tube and the molecules of water, as well as the attraction among the water molecules themselves. The forces of attraction balance the gravitational force of the column of water that rose to a specific height. Furthermore, the narrower the opening of the capillary tube, the higher the water rises.

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What insect has the shortest life span?

Despite there being more than 2,000 species scattered around the world, mayflies depend on their quantity for survival. Each species has a different average lifespan. Mayflies have four stages in their life cycle: egg, nymph, subimago and imago. A female mayfly lays anywhere from 50 to 10,000 eggs in the water, which hatch in about two weeks. Nymphal life may last up to two weeks and includes as many as 50 molts, or sheddings of the skin. When growth is complete, the nymphal skin splits and wings emerge; a mayfly is then in the subimago stage. This stage lasts anywhere from several minutes to ..

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How many electrons, protons and neutrons does chlorine have?

The atomic number is the same as the number of protons while the mass number is the sum of the protons and neutrons. A chlorine atom has a mass number of 35. Subtracting 17 from 35 equals 18, which is the number of neutrons in a chlorine atom. In the periodic table, all elements are represented by their chemical symbol with the mass number written on the top-left portion and the atomic number on the bottom-left.

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What is the function of the tympanic cavity?

The tympanic cavity is also referred to as the middle ear. It is an air-filled and membrane-lined area located between the Eustachian tubes and ear canal.\nThe middle ear plays an important role in hearing. Inside this cavity the mucus membrane covered ossicles form a small chain and carry sound vibrations into the inner ear. Sounds are converted into nerve impulses as soon as they enter the fluid-filled inner ear. These nerve impulses are then sent to the brain.\nThe middle ear also plays a role in maintaining equalized pressure in the head. This area is pressurized, and the pressure is maint..

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What is the function of the spongy layer?

The function of the palisade mesophyll layer is the absorption of light because this layer also has many more chloroplasts that the spongy mesophyll. Besides the chloroplasts, some other structures found inside the leaf are the upper and lower epidermis and guard cells, which also have chloroplasts. The guard cells are found around a stoma and regulate the stoma's opening or closing to facilitate gas exchange.The outer part of the leaf consists of veins, leaf blade and stomata. The exchange of carbon dioxide gas and other substances in the leaf occurs through the stoma, which is a tiny ap..

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