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Where does protein synthesis take place?

Ribosomes bind mRNA and translate it into a protein. They reside in the cytoplasm and bind to the endoplasmic reticulum. In both states they translate mRNA into proteins that are important for cellular processes. Where any particular protein is synthesized depends on the post-translational modifications and where the protein ends up being placed or used. Proteins meant for the ER often have a signal sequence at the very beginning of translation that makes it so ribosomes in the cytoplasm are "captured" as they begin translation. They are stuck to the ER, and the protein they translate is moved..

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How many phases does the moon have?

The eight phases of the moon are new moon, waxing crescent, first quarter, waxing gibbous, full moon, waning gibbous, third quarter and waning crescent. Many people believe that the phases of the moon are the direct cause of Earth's shadow when it falls on the moon. This is actually not the case. The phases of the moon are the direct cause of the angle of the sun. The moon's current position is always between Earth and the sun. The side of the moon that faces Earth receives no direct sunlight. The only sunlight it receives is the dim sunlight that the Earth reflects. As the moon move..

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What is the difference between a tendon and ligament?

Both tendons and ligaments are fibrous tissues designed to connect parts of your body. This tissue is tougher and less flexible for tendons and stringier and more elastic for ligaments. However, both tendons and ligaments require some degree of flexibility to accommodate movement; rigid tendons and ligaments would prevent basic body movements.\nWhen tendons and ligaments are stretched beyond their basic capacity, they become damaged. For tendons, this can result in tendonitis, which occurs when the tendon becomes torn. This damage causes the tissue of the tendon to inflame while it heals; as a..

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How does rhyolite form?

Rhyolite lava is thick and flows slowly but cools quickly. When rhyolite magma explodes, the overall temperature is generally low. Most rhyolites crystallize quickly on the surface of Earth, resulting in a groundmass that consists mainly of small crystals or small glassy crystals. An igneous rock that often crystallizes before surfacing, rhyolite forms complex chains of silicate minerals. Rhyolite magma that is rich in gas tends to form porous rocks, such as pumice. Porous rhyolitic magma that is able to flow can result in degassing and the formation of glassy rocks, such as obsidian. The form..

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What is the purpose of floating ribs?

Also known as the vertebral ribs, floating ribs are the two pairs of lowermost ribs, numbered 11 and 12, positioned on each side of the rib cage. They attach to the backbone alone, unlike the other ribs that attach to the backbone and also attach directly or indirectly to the breastbone. This anatomy makes them appear to float, hence the name floating ribs.

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What is the difference between homozygote and heterozygote?

Organisms inherit one allele from each trait from both of their parents. Typically, the terms heterozygote and homozygote are used when the traits in question are Mendelian; that is, they are determined by a single gene. Of the alleles for that gene, one is typically fully dominant over the other. A dominant allele in Mendelian genetics is always expressed over a recessive one. A heterozygote generally has one copy of both the recessive and dominant alleles for a trait, resulting in an organism that expresses the dominant trait yet can pass the recessive trait onto its offspring, according to ..

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What is the modern model of the atom?

Unlike the more common Bohr depiction of the atom that involves point-particle electrons orbiting the nucleus in fixed, circular paths, electrons in modern atomic theory exist as waveforms surrounding the nucleus.These electron waveforms exhibit both particle and wave properties and are described by the Schrodinger wave equation. The uncertainty principle of quantum mechanics makes it impossible to determine exactly where an electron is around the atom; so instead, volumes that have a high probability of having electrons are defined. The probability in these volumes ranges between 0's at ..

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How do you measure length, width and height?

Choose a unitWhether you opt to measure in inches, millimeters or another unit of measurement, it is important to use the same unit for all three measurements.Choose a measuring deviceThe measuring device you should use depends on the size and location of the object you are measuring. A ruler can be used for small objects, while a tape measure is preferable for larger ones or objects that are harder to reach.Measure all of the sidesNote that when you place the object flat on a surface, the height is the dimension from the floor to the topmost part of the object. When measuring the other sides,..

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What is the function of red bone marrow?

While red marrow also removes damaged red blood cells from the blood, this job is also carried out by the spleen and liver. About.com states that the red marrow contains an abundance of blood vessels, which keeps the tissue well nourished. Yellow marrow, which primarily resides in spongy bones and the shafts of the limb bones, serves as a storage site for fat. If a person suffers from extreme blood loss, the body can convert yellow marrow to red marrow. The new red marrow can then produce replacement blood cells.\nRed bone marrow is part of the body’s lymphatic system, according to About.com..

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Why are protists important to humans?

Protists are mostly unicellular organisms; some species are more plant-like, and other are more animal-like. Diatoms are a type of plant-like protist that lives mostly in fresh water. Present in huge numbers, they serve as the basis of the food chains in these fresh water habitats, securing energy through photosynthesis. Without diatoms, the larger animals like fish and clams, upon which humans feed, would not be present. Another type of plant-like protist is red algae, which lives in marine environments and produces agar, the medium that is used as a base for culturing bacteria in laboratorie..

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