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What is the difference between local winds and global winds?

Each hemisphere has three global winds: the polar easterlies, the prevailing westerlies and the trade winds. They are named for the direction in which they blow. According to the University of Illinois, the polar easterlies range from 60 to 90 degrees latitude. The prevailing westerlies, which is known simply as the westerlies, range from 30 to 60 degrees latitude, and the trade winds range from 0 to 30 degrees latitude.\nThe trade winds blow mostly from the southeast to the Equator and is the route that sailors prefer because of its steady and warm tropical winds. Christopher Columbus is thou..

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What part of the eye contains the sensory receptors for sight?

The sensory receptors of the retina are called rods and cones. Rods, which are the more numerous receptor type, provide vision in dim light, but vision coming from the rods is poor in quality. Cones are responsible for vision in bright light and provide great visual acuity.\nAt the center of the retina is a small area called the fovea, which provides the sharpest vision of the entire retina. The fovea contains many cones but no rods. The layers of the retina come together to form the optic nerve, a bundle of fibers that transmits visual information from the eyes to the brain.

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How are valley glaciers and continental glaciers different?

The primary difference between the two types of glaciers is size. Continental glaciers cover large swaths of land and extend over 50,000 km, meanwhile valley glaciers are confined to mountains and don't exceed lengths of 100 km. Continental glaciers are also far thicker, they bury the land in up to thousands of meters of ice, completely transforming the landscape. Valley glaciers, however, can be viewed as rivers of ice, far thinner with numerous tributary glaciers that join to form the main glacier.\nIn addition, continental glaciers usually move very little. Valley glaciers, on the othe..

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How many miles are there to outer space?

Prior to the adoption of the Karman line, the boundary of space had been set at 50 miles, according to Universe Today, and pilots who exceeded this boundary were eligible to wear astronaut's wings. The modern definition takes physical forces into account. Above the Karman line, a flying object derives more lift from orbital velocity than it could from the flow of air over its flight surfaces.

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How does temperature affect battery power?

All batteries rely on an internal chemical reaction to produce an electrical current. When the temperature drops, the rate of this chemical reaction is slowed, thereby reducing this current. When trying to start your auto in winter months, the reduced current in a car battery is exacerbated by the fact that motor oil thickens in cold temperatures, thereby requiring more power to get the engine moving than when it's warm. Combine these two factors, and all car batteries reach a point as the temperature drops where they just can't start the car.\nConversely, when the temperature rises,..

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What are some of the abiotic factors in a chaparral ecosystem?

In the United States, chaparral ecosystems are found primarily in California, where they cover about 5 percent of the state. Wildfires are a significant abiotic factor. If they are infrequent or absent, conifers may invade the biome's shrub communities. Human intervention in the form of fire suppression can enable an invasive plant species to displace the shrub communities.Some herbaceous and annual chaparral plant species are dependent on frequent wildfires to clear space so that ample sunlight can reach them. When the overstory regrows, dormant seeds will be dormant until the aftermath ..

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What is the role of spindle fibers in mitosis?

Spindles are made up of microtubules and proteins. They extend from areas on the sides of the cell called centrioles on each end of the cell or at each pole. The spindles attach to the and attach directly to the chromosomes. Once the spindles are attached they do not simply pull the chromosomes apart, they first align them, and then proceed to separate them. The spindles do not grow without a type of balance in place.The system that monitors the spindles and makes sure that the process of anaphase happens at the correct time is the kinetochores. The spindles are not completely round like the n..

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What is the definition of living things?

Sometimes movement is also listed as a key characteristic of life, but many living things, such as trees, mushrooms, barnacles and coral, are incapable of movement during some or all of their life stages. Viruses, on the other hand, are a special case of an organism that is not a living thing. Although viruses are unable to reproduce or take in energy on their own, they are classified as organisms because they still contain genetic data and have evolutionary lineages. Furthermore, viruses are capable of reproducing within host cells and exist independently of their hosts, even if they are inan..

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What were Homo habilis shelters?

Homo habilis were not considered cave-dwellers because it is believe fire was not yet discovered, and primarily constructed their homes from earthen materials, such as stones and branches. They compiled large amounts of stones, which may have served as methods of defense, and were also used to protect inhabitants from the elements, carve weapons and contain fires.

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What is the importance of Kingdom Animalia?

According to the Sidwell Friends School, animals have a profound impact on all other forms of life on earth. Animals influence the composition of the atmosphere, consuming oxygen and releasing carbon dioxide. As the largest mobile organisms on earth, they even affect the landscape around them. Many animals dig burrows, while beavers dam rivers to create ponds and elephants dig up underground water sources. Humans are also considered animals and no other animal has done more to change the makeup of the Earth's surface.\nPlants, in particular, show the profound influence animals have had on..

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