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Where do animals live?

Rain forests are the world's most ecologically diverse biomes. According to Mongabay founder Rhett Butler, roughly half of all animal species reside in rain forests. These areas also contain more plant species than any other environment. Rhett Butler remarks that a hectare of rain forest contains up to 460 tree species, plus other flora such as ferns, flowering plants and vines.\nSome of the most unusual animals live in ocean environments so deep that they receive no sunlight. The Smithsonian Institution reveals that some deep sea denizens are extremely difficult to see because they have ..

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What does a nucleotide consist of?

Nucleotides are organic molecules that make up the basic units of DNA and RNA molecules. Nucleotides carry energy within cells and are important in metabolism and cell signaling. The combination of a base and a sugar is a nucleoside. In biology, the term nucleotide most often refers to a nucleoside monophosphate. However, a nucleoside diphosphate or a nucleoside triphosphate may also be considered a nucleotide.

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How are animals and plants different in getting their food?

Because plants produce their own food, they are known as producers. Animals are called consumers because they must eat plants or other animals to stay alive. Primary consumers, also called herbivores, are plant eaters. Deer eat the leaves, buds and needles of trees and shrubs.\n\nSecondary consumers, called carnivores, eat other animals. The lion is an example of a carnivore. Omnivores eat both plants and animals, giving them a wider variety of foods to consume. Bears are omnivorous because they eat berries as well as elk, bison and other animals.\n\nOther plants and creatures in the world of ..

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What organ serves a major hemolytic function?

The spleen usually removes broken down red blood cell fragments from the bloodstream, explains the National Heart, Lung and Blood Institute. Inherited hemolytic anemia causes abnormal red blood cells due to faulty genes. The abnormal red blood cells break down prematurely and are removed by the spleen. An oversized spleen is another cause for extrinsic hemolytic anemia. Additional causes include infections, certain medications and blood transfusions.

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How long did the Paleozoic Era last?

The Paleozoic Era began about 540 million years ago and ended 248 million years ago. The supercontinent of Pannotia broke apart, and Pangaea formed from fragments of Pannotia during the Paleozoic.\nAt first life forms were confined to the Cambrian oceans, but later during the Ordovician, plants began colonizing the land. At the end of the Paleozoic Era, a cataclysmic mass extinction caused the disappearance of 90 percent of all marine animal species. This was the biggest mass extinction in history.

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What does the mesosphere contain?

The mesosphere is the layer of the Earth's atmosphere that is directly above the stratopause and directly below the mesopause. The mesosphere starts at 50 km (31 miles) above the Earth's surface and goes up to 85 km (53 miles) high. In the mesosphere, temperature decreases with increasing height. The coldest temperatures in Earth's atmosphere, about minus 90 degrees C (minus 130 degrees F), are found near the top of this layer.\nScientists know less about the mesosphere than about other layers of the atmosphere. Weather balloons and jet planes cannot fly high enough to reach the..

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How do you insert a male catheter?

Inserting a male catheter is a sterile procedure, so wash your hands and wear sterile gloves. The OSCE Skills website states that you should retract any foreskin and clean the penis around the urethral meatus. Hold the penis with a sterile swab while inserting the lubricant gel. Advance the catheter into the urethra while ensuring that your hand does not touch the penis in order for the catheter to remain sterile.\nThe catheter is fully inserted once urine starts flowing through it, notes the Queens University School of Medicine. At this point, inflate the balloon using saline. The volume need..

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What is the difference between a natural & artificial ecosystem?

A natural ecosystem is the result of interactions between organisms and the environment. For example, an ocean is classified as a marine ecosystem, which consists of algae, consumers and decomposers. A cycle occurs in this type of ecosystem that begins with algae converting energy via photosynthesis. After consumers feed on the algae, energy is transferred between the organisms. Once consumers die in this system, decomposers turn them into organic matter. This process occurs naturally over a period of time, whereas in an artificial ecosystem, human intervention is required.\nAn artificial ecos..

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What occurs within a muscle cell during oxygen debt?

The use of glucose is far less efficient than usual in a muscle cell accumulating oxygen debt. Each glucose molecule broken down into lactic acid only gives about 5 percent of the energy a glucose molecule would give with sufficient oxygen. This lactic acid contributes to muscle fatigue and failure. Once the high energy use stops, the lactic acid is combined with oxygen to form carbon dioxide and water just as with normal aerobic respiration.\nLactic acid fermentation is a type used by both muscle cells and some bacteria. Other bacteria and yeasts use ethanol fermentation, creating alcohol ins..

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What are some interesting facts about black holes?

NASA mentions that black holes form when the center of massive stars collapse from within. Black holes cannot be seen because the gravitational pull forces light into the hole's center.\nBlack holes are comprised of three layers that include the singularity and the inner and outer event horizons. The singularity is the point where space and time are concentrated, and it is the mass of the hole. The event horizon is the lining of the black hole's mouth where light is unable to escape.\nA person falling into a black hole would become increasingly elongated and would die before reaching..

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