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What is the function of Reverse Transcriptase?

Reverse Transcriptase is key to the replication of many viruses, including retroviruses. Reverse Transcriptase generally acts as "RNA dependent DNA polymerase," transcribing the single-stranded DNA that comes from the viral RNA. It also demonstrates the activity of Ribonuclease H, a subunit of the Reverse Transcriptase enzyme. Finally, Reverse Transcriptase acts as DNA-dependent polymerase, transcribing the secondary DNA strand, which is complimentary to the first DNA strand.

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How are fossils formed?

Carbonization is another common method of fossil creation and is often seen as an impression in sedimentary rock. This process occurs when the heat and pressure from a buried organism causes the release of available oxygen and hydrogen in the tissues, leaving behind a tell-tale carbon residue on the rock around it.\nAnother less common method of fossilization is the encasement and preservation of an entire organism, soft tissues and bones alike. This type of fossil results from a sudden encasement in tar or resin or the quick freezing of an animal, such as a woolly mammoth.\nFinally, a fossil ..

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Do all animals have skeletons?

Invertebrates far outnumber vertebrates. Ninety-eight percent of all animals do not have a backbone or skeleton. Insects are one of the largest groups of invertebrates, but other animals that do not have an internal skeleton include worms, crustaceans like shrimp and crabs, and mollusks, like squids and snails. Invertebrates may have a hard shell called an exoskeleton. Vertebrates are generally much larger than invertebrates.

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What would happen if there was no cell membrane?

The cell membrane provides several vital functions for the cell. Cell walls anchor the cytoplasm and hold the cell's shape. It is a selective, semipermeable membrane that allows the cell to maintain homeostasis by regulating what it allows into the cell. Cells absorb nutrients through the cell membrane and expel waste through the same membrane using both active and passive transport. In plants, fungi and some bacteria, an outer cell wall provides mechanical support for the organism. In complex organisms, the cell wall attaches to the cell walls of other cells to form tissues, organs and u..

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What are some scientific names for mushrooms?

The morel is known as Morchella esculenta in the scientific community. The morel is a eukaryote fungus and reproduces using spores. The fleshy mushrooms belong to a family of edible mushrooms known as Morchellaceae. The word "morchella" comes from the word "morchel," which is German for mushroom.\nOne of the largest living organisms on Earth is the fungus Armillaria bulbosa, or the honey mushroom. One honey mushroom patch near Crystal Falls, Mich., covers 38 acres and weighs approximately 100 tons. The huge patch grew from a single spore and lives just beneath the surface of the Earth.\nThe sh..

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Is it possible to have twins from two different dads?

In May 2015, The New Jersey Law Journal and The New York Times reported an unusual case in Passaic County, New Jersey. A mother of twins applied for child support, claiming that her former partner was responsible for both of her children. In testimony, however, she admitted to a second relationship with a different, unidentified man. She had this relationship within a week of her relations with her first partner. The court ordered a paternity test, which found that her former partner was responsible for only one of the twins. It was a landmark decision.But how is this scientifically possible? ..

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What is the limit of resolution of the human eye?

The resolution limit of any imaging system is limited by diffraction: how light behaves when shone through a circular aperture. The Raleigh criterion for a circular aperture is sin(theta) = 1.22*(wavelength/distance), in which theta is the resolution limit. However, the resolution limit dictated by the Raleigh criterion for an iris equal to 5 millimeters and a wavelength equal to 500 nanometers is 1.22*10^(-4) radians, meaning that the resolution limit of an eye is not solely dictated by diffraction and that there are biological factors involved.

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What is uranium ETF?

Nuclear power plants are among the primary consumers of uranium. This ties uranium ETFs closely to the nuclear energy industry. Uranium ETFs provide investors with an opportunity to invest in an area related to nuclear power without the need to research individual stocks. Uranium ETFs also have general advantages related to all ETF investments. Because ETFs involve trading groups of investments in one transaction, they have lower commissions compared to those incurred by trading individual stocks.

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What is an ebb tide?

When an ebb tide reaches its greatest distance from land, the water in the tide experiences a period of no velocity. This is called slack water. After the slack water stage is over, the water moves back toward land in a flood tide of increasing velocity. Tidal currents are affected by the different phases of the moon. When the moon is full or new, tide velocity increases. A first or third quarter moon weakens tide velocity.

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What is energy that can move through empty space?

Electromagnetic radiation travels in waves through empty space but is also simultaneously propagated by particles such as electrons and photons in a phenomenon called wave and particle duality. The different types of electromagnetic radiation are determined by wavelength, which also corresponds to energy. Radio waves have long wavelengths, measured in meters, and have relatively low energy. Light waves have short wavelengths, measured in nanometers, and much higher relative energy.

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