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Why are zoos good for animals?

Many reputable zoos in America and other countries are part of the Species Survival Plan Program. Under the guidelines of this program, the participating zoos help increase the numbers of animals such as the California condor, red wolf and black-footed ferret, all of which were once on the verge of extinction.This type of program is always a work in progress, and some animals, such as the Andean condor and lowland gorilla, have not enjoyed as much success as others on this list. With the help of zoos, however, their numbers may rise.

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What does (NH4)2S represent?

Ammonium sulfide is sometimes used in photography, metal finishing and the creation of textiles. Ammonium sulfide is also commonly used for pranks, creating the foul scent for which stink bombs are known. This chemical is also known as "diammonium sulfide," a name that more accurately represents its chemical formula.\nThe chemical formula of ammonium sulfide is represented by two parts. Ammonia is signified by NH4, and the two outside the parentheses means that ammonium sulfide is made of two parts ammonia. Sulfur is represented by S in the formula, meaning the chemical is one part sulfur. Che..

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What is the element "Nu"?

Sodium is an alkali metal with the atomic number 11, while nitrogen is a non-metal with the atomic number seven. Neon is an inert gas, and its atomic number is 10. Gold is a transition metal; its number is 79, so it is the heaviest of the elements listed here. The atomic number represents the number of protons in the nucleus of an atom, so a sodium atom, for example, has 11 protons.

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What is the Jominy end-quench test?

The Jominy test uses a round steel bar that is heated to transform it into austenite. The bar is then quenched with room temperature water on one end. The bar is then cooled. A flat surface is then rubbed on the bar to measure the hardness of the bar. The hardenability is lower on the quenched end and increases as the distance from the quenched end increases. The results are plotted on a distance/hardenability graph, which can then be compared with other steel specimens. The test was invented by Walter E. Jominy and A. L. Boegehold in 1937 when they were metallurgists at the Research Laborator..

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What are "wormholes"?

Albert Einstein’s theory of relativity gives theoretical physicists the basis of the wormhole hypothesis. The theory claims that mass changes the structure of space. Theoretical physicists postulate that black holes are a possible entrance for a wormhole and white holes serve as the exit to a different destination. Wormholes are unstable, and small changes in mass surrounding the tunnel or inside the tunnel causes the wormhole to collapse.

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What is a mechanical barrier in the immune system?

The immune system is a complex series of protective measures that defends the body against infectious microorganisms, cancer cells or transplanted tissues or organs. An immune response is triggered when the immune system detects foreign invaders. This auto-response combats potentially pathogenic elements.The immune system comprises defensive mechanisms such mechanical barriers, white blood cells and molecular components, such as cytokines, complement proteins and antibodies. Mechanical barriers, otherwise known as physical barriers, are considered as the most crucial line of defense.

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Where does gaseous exchange take place?

Oxygen and carbon dioxide are exchanged in tiny air sacs called alveoli, which are found at the end of the bronchial tubes of the lungs. Capillaries surround these alveoli. Oxygen moves from the alveoli to the capillaries and enters the bloodstream whenever a person inhales. Simultaneously, carbon dioxide is breathed out of the lungs as a person exhales. This is how gaseous exchange occurs in the alveoli.\nAlveoli have several adaptations to maximize the efficiency of gas exchange. They fold to provide a wider surface area for gas exchange to take place, and they are ventilated to remove waste..

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What is the function of the appendicular skeleton?

The University of Pennsylvania Health System explains that the appendicular skeleton is so named because the constituent bones lie outside of the body’s axis. The pelvic and pectoral girdles are the primary place in which the axial and appendicular skeletons meet. The pectoral girdle is comprised of two clavicles and two shoulder blades, while the pelvic girdle is comprised of two large hipbones. Each hipbone is actually comprised of three bones that have fused together. These bones are called the ilium, ischium and pubis bones.\nIn addition to serving as a site to which the femurs can attac..

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What hormones are secreted by the islets of Langerhans?

The endocrine pancreas secretes hormones that are vital in maintaining healthy blood-sugar levels. Type 1 diabetes occurs when an autoimmune process destroys the beta cells of the islets of Langerhans, and the body is no longer able to produce insulin. Lifelong injections of pharmaceutical insulin or transplantation of donor islet cells can correct Type 1 diabetes.

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What is the difference between a cave and a cavern?

Caves and caverns occur naturally, and the two terms are often used interchangeably. Volcanic activity, microogranisms, pressure, water erosion and chemical actions contribute to the formation of caves and caverns. Sea caves, sometimes filled with water, are found along the coasts of oceans and seas. They are created by tidal activity that constantly weakens and erodes the rocks located there.

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