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What are some of the advantages and disadvantages of recombinant DNA technology?

Direct manipulation of organisms' genes has unlocked a new world of speed and efficiency in selective breeding. By cutting and swapping genetic sequences, scientists are able to skip the lengthy, very wasteful process of cross-breeding and selective culling of organisms. Often, a direct gene swap can introduce the desired trait within a single generation, according to IfGene. This has permitted the economical production of insulin by bacteria, the improvement in agricultural yields and the distribution of an effective hepatitis B vaccine.\nIfGene also notes several serious drawbacks to un..

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What is an example of thermal pollution?

Thermal pollution arises when an artificial heat source enters an environment that cannot handle it. When this happens, the environment may become warmer than is normal for that time of year. This most often applies to the air and natural water sources. One example of this are factories. Many are located next to water sources and take cold water and replace it with hot water once they are finished with it. When that water source becomes warmer, it is no longer within the normal environmental range for the plants and animals that live there. As such, they may begin to decline. One way this decl..

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What is retrograde motion?

Although it baffled many ancient scientists, current astronomers have since established that retrograde motion is an illusion caused only by the Earth’s motion. According to Scienceu.com, it was practically unbelievable that a heavenly body would change its direction, only to reverse it a while later.\nOf all the satellites known in existence, only a minority tend to display retrograde rotation. These include Phoebe, Saturn’s outermost moon; Jupiter’s four outermost moons; and Triton, Neptune’s largest moon. The revolution of all the asteroids around the sun is known to be direct. Of a..

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When did Hurricane Katrina occur?

According to the New Orleans Times-Picayune, August 29, 2005, was a day that has forever changed New Orleans. Hurricane Katrina first appeared as a tropical depression on Wednesday, August 24, 2005. By Sunday, August 28, the storm had been upgraded to a hurricane that developed to Category 5 proportions. New Orleans' mayor ordered a citywide evacuation at 9:30 a.m. on the 28th, an order that some ignored or could not comply with, leaving thousands of residents vulnerable both to the storm and the resulting levee flood damage.

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What are some of the United States' natural resources?

National Geographic explains that the natural resources allow the economy to continue by way of exporting many of these natural resources. These resources contribute to millions of jobs, and they aid the United States by way of manufacturing and production of these resources. The 94,000 mile coastline allows for shipping easily to other countries, states National Geographic.\nThe fertile soil allows for production of many types of crops for the United States and exporting some of the crops overseas. The timber industry is very strong in the Pacific Northwest, South Atlantic and the Gulf States..

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What causes a bone stress fracture?

Stress bone fractures typically occur in the bones of the legs and feet. The individuals most at risk for developing stress bone fractures are those who participate in sports, have active lifestyles or suddenly increase physical activity. For instance, someone who regularly jogs is at a greater risk for a bone stress fracture than an individual with a more sedentary pastime. Individuals who suffer from flat feet, high-foot arches or degenerative bone diseases, such as osteoporosis, are also at increased risk for bone stress fractures.\nSlowly building an exercise routine and adding low-impact ..

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What is the weather in freshwater biomes?

Weather in freshwater biomes varies with the seasons and geographical location. Some ponds and lakes occur seasonally, filling in natural beds with ample spring and summer rainfall. The extra moisture evaporates into the air, moderating temperatures and producing local conditions such as haze and fog. The temperature of water in these aquatic bodies fluctuates with the seasons, changing physical composition. Colder water forms ice in some lakes and ponds during the winter, reducing the activity of organisms within.The temperature and conditions of streams and rivers varies, fluctuating with th..

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Where is iodine found in the world?

Iodine's initial discovery came as the result of an examination of seaweed, and because the oceans are abundant with the mineral, seafood and seaweed are two of the of the best dietary sources of this nutrient for human consumption. Seaweed alone can be as much as 45 percent iodine. Table salt is often fortified with iodine, making it an alternative choice for those wishing to add this important nutrient to their diet.

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What is the function of the terminal cisternae?

In the skeletal muscle, two terminal cisternae merge with a T tubule to form a triad structure. When a muscle is stimulated, calcium is released from the storage unit of the terminal cisternae. This calcium binds with troponin-C in the sarcoplasm to execute the muscle contraction.\nCalcium's role as a muscle contraction activator was discovered during 20th century experiments on frog tissue.

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What did Galileo Galilei discover?

When Galileo Galilei was a student, his father sent him off to the University of Pisa in the hopes his son would study medicine. However, Galilei had other plans and studied math instead. After graduating from the university, he stayed on as a math professor and made several important discoveries in physics. Galilei wrote "Principles of Inertia" which is similar to Newton's First Law.Once he became interested in astronomy, he built his first telescope in 1609, which helped him discover Jupiter's largest moons. He also discovered many new stars, the phases of Venus, and sunspots. By l..

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