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What is the SEO2 Lewis structure?

Selenium dioxide is a colorless solid that consists of a one-dimensional polymeric chain with alternating atoms of selenium and oxygen. It is an acidic oxide and dissolves to form selenous acid. Selenium compounds are poisonous and contain a strong odor. Because of this, working with the compound requires appropriate fume hoods and precautions.\nIt is used in the Riley oxidation. The reaction is carried out using a catalytic amount of SeO2 with the addition of an oxidizing agent like t-butyl hydroperoxide. This re-oxidizes the selenium (II) compounds after each cycle of the reaction and elimin..

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What is a filament of a plant?

The filament and anther are part of the system that is essential for the plant to reproduce. Before a flower bud opens and produces and releases pollen, it is encased in protective leaf-like growths called sepals. When a flower bud opens, its petals typically serve to attract insects and other animals that carry pollen to other plants, thus enabling fertilization. Some flower petals possess scents that draw insects to them.

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Where does spermatogenesis occur?

Spermatogenesis is a three-phase process that turns stem cells into spermatozoa. The cells undergo spermatocytogenesis, meiosis and spermiogenesis. During spermatocytogenesis, or mitosis, cells divide to produce cells for differentiation. In meiosis, chromosomes in the stem cells are reduced to amount present in mature sperm. The sphere-shaped spermatids change into elongated spermatozoa during spermiogenesis. After these process are complete, the spermatozoa is released into the opening of the seminiferous tubules.

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What is a side vent in a volcano?

The eruption primarily goes through the main vent, but there can be various other secondary vents as well where smaller amount of magma escape. The vents act as channels for the magma coming from the chamber to the ground's surface. The different types of volcanoes have different structures and can have many side vents.

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What is a slightly movable joint?

Joints can be classified on the basis of structure or function. Structural classification deals with the manner in which the bones are connected, while functional classification has to do with the range of motion that a joint allows.\nAmphiarthrosis is a functional joint class. The other two are synarthrosis, which allows for restricted or no mobility, and diarthrosis, which permits free mobility.

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What class lever is a hammer?

There are three classes of levers. The difference between the classes lies in the position of the load, the effort and the fulcrum. When the fulcrum is between the load and effort, the object is a first class lever. If the load is between the fulcrum and effort, the object is a second class lever. A third class lever places the effort between the load and the fulcrum.

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What is primary endosymbiosis?

This hypothesis explains many features of mitochondria and chloroplasts. These structures have their own DNA, for example, that is organized in a ring shape common to bacteria but unknown among eukaryotes. A likely explanation for the partnership between cell types is that a nucleated cell absorbed a bacterial cell, without digesting it, and came to rely on the nutrients its "prey" secreted.

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How long do yellow jackets live?

In the spring, a new queen emerges from underground, builds a nest and lays her eggs. Then workers emerge to help care for the eggs. The eggs hatch; larvae emerge, mature by the end of summer and then leave the nest to mate. After mating, the yellow jackets bury themselves underground to wait out the winter and restart the cycle again the following spring. The adult workers, males and the old queen die in the fall.

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How does EMG testing evaluate nerve damage?

EMG measures and interprets electrical activity via electrodes, and shows the information in visual or audio format. According to Mayo Clinic, there are several methods of assessing electrochemical activity using EMG. A needle electrode directly measures the motor neuron activity within a muscle. A nerve conduction study is used to measure the activity within a specific muscle or along a nerve via electrodes on the skin. A nerve conduction study can show if the motor neurons within a muscle are sending strong or weak signals, and it also assesses signal speed.\nDoctors may order an EMG in pati..

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What are some Hurricane Katrina facts for children?

Hurricane Katrina began forming over the Bahamas on August 23, 2005. It first hit land in Southern Florida on August 25, causing minor flooding and two casualties. Large areas of Mississippi, Alabama and Louisiana were destroyed by Hurricane Katrina, causing estimated damage of $81 billion. Eighty percent of New Orleans was flooded and remained flooded for weeks. It is labeled as the costliest natural disaster and is one of the five deadliest storms in U.S. history.\nThe environmental impact included beach erosion, the destruction of breeding grounds for animals and the forced closure of 16 Na..

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