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Where can carbon be found?

In addition, natural diamonds are found in the mineral kimberlite, which exists in South Africa, Arkansas and some other places. Diamonds are also found on the ocean floor off the Cape of Good Hope. Carbon is also found in the fossilized remains of living things as hydrocarbon gases, crude oil, oil shales, coal and other substances. It is also found in the form of carbonates such as chalk limestone and dolomite.\nSince all living things contain carbon, it was once though to hold a "spark of life." Living things get almost all of their carbon from carbon dioxide, through the atmosphere or disso..

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What is considered low humidity?

While the humidity of outdoor air cannot be controlled, the humidity of a home's air can be controlled with humidifiers and dehumidifiers. Just as the humidity can be too low, it can also be too high. The point at which there is too much moisture in the air is about 50 percent humidity. Beyond this level of moisture, things like mold and bacteria can grow quickly and cause both short-term and long-term breathing problems.

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What is netted venation?

Examples of plants with netted venation include maple, oak, hibiscus, redgram and rose. Net venation is also known as reticulate venation, and is further classified into pinnate and palmate venation. Pinnate venation is as well-known as unicostate venation, while palmate venation is also known as multicostate venation.\nIn pinnate venation, the veins extend crossing the midrib to the circumference, as seen in apple, mango, peepul, guava, cherry and peach plants. Pinnate venation typically shows one vein more outstandingly than the others, and consists of veins that run from the base of the lea..

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Why does the moon shine?

Lunar soil is not exceptionally reflective, so the sunlight that does fall on the lunar surface tends to be either absorbed or scattered. This leaves relatively little light that can bounce back toward observers on Earth. Despite its poor reflective index, the moon is relatively large and very close to Earth, making it one of only three objects in the sky, along with Venus and the sun, bright enough to cast a shadow, according to Universe Today.\nThe moon varies greatly in apparent brightness throughout the monthly lunar cycle. According to Wikipedia, the Moon is at its brightest when it'..

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What cells undergo meiosis?

Meiosis is necessary for sexual reproduction, which allows for greater genetic variation in a species. Single-celled organisms that reproduce by mitosis produce two identical daughter cells. Genetic variation only occurs by spontaneous mutations in the organism. By contrast, organisms that reproduce using sexual reproduction combine two sets of genetic material, one from the male and one from the female, to form offspring that are genetically distinct from their parents.

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What is the effect of acetylcholine on heart rate and blood pressure?

Acetylcholine is a neurotransmitter, or a chemical that transmits signals throughout the brain and body. According to The Merk Manual, acetylcholine generally has inhibiting effects such as slowing the heart rate and decreasing blood pressure, but it also causes some sympathetic effects such as increased sweating or making hair stand on end. The National Dysautonomia Research Foundation emphasizes that acetylcholine is one of the chemicals that manage the transmissions between nerve endings and their corresponding organs.\nWhile acetylcholine slows heart rate and blood pressure, another chemic..

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What are closely stacked flattened membrane sacs called?

The Golgi apparatus is closely associated with another structure called the endoplasmic reticulum, which produces the substances that the Golgi apparatus packages. Each Golgi apparatus has two sides: the cis face and the trans face. The cis face is the entrance point for substances made in the endoplasmic reticulum. Substances are then packaged into vesicles that exit from the trans face of the Golgi apparatus. The Golgi apparatus usually has its cis face close to the endoplasmic reticulum, whereas its trans face is positioned near the cell membrane.

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How much time is required to renew a Trinidad passport?

A person who applies and picks up the passport in person, for a non-machine readable passport renewal, must allow five business days after the application date, states the Consulate General. As of 2015, the passport may be picked up on weekdays until 3 p.m., excluding holidays. A person who applies in person and has the passport mailed, or a person who applies by mail and has the passport mailed, must allow 10 business days. If a third party is assigned to pick up the passport for an individual who applied in person, a third-party authorization form must be downloaded from the website and fill..

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What kind of tissue forms kidney tubules?

The kidneys are vital organs that filter waste, removing it as urine, and are a part of the sophisticated urinary system. The human body has two kidneys, that, according to WebMD, contain about one million tiny nephrons, each made up of a filter that is attached to a tubule.\nIn the process of filtration, the kidneys retain as much water, sugars and salts as possible while filtering out the waste products, such as urea, states the Kidney & Urology Foundation of America. The tubules, often referred to as the renal tubules, reabsorb the beneficial solutes and water back into the body while conti..

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Why did people once believe that Earth was the center of the Universe?

In the early 1500s, Nicolaus Copernicus published the first major theoretical work that challenged the notion of an Earth-centered universe. Copernicus theorized a sun-centered universe, or a heliocentric solar system. In 1610, Galileo Galilei was able to use the first telescope to study the solar system. He strengthened the argument for a heliocentric system by noting changing levels of brightness during the rotations of certain planets as well as the Earth's moon and the sun.

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