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How is body temperature maintained?

Humans regulate the generation and preservation of heat in order to maintain internal body temperature, which is also called core temperature. Normal core temperature at rest lies around 98.6 degrees Fahrenheit. The hypothalamus triggers changes to effectors, such as sweat glands and muscles that control body hair. When the weather is hot, temperature receptors in the skin send signals to the hypothalamus, causing an increase in sweat to cool the body.\nBBC explains that the skin has temperature receptors that detect changes in external temperature. There are also receptors that detect tempera..

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For what is DNA used?

It is possible to identify and assess genetic information via DNA fingerprinting. This process can be used to determine biological relationships, diagnose various genetic disorders, establish whether or not an individual is carrying a genetic mutation that can be passed on and reveal whether a person is at risk for certain genetic diseases. DNA testing is also used in forensic science and plays an important role in law enforcement. DNA information is unique to every individual, which makes it easier to identify suspects..

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Is oxygen a compound?

Oxygen was discovered by Carl Wilhelm Scheele and Joseph Priestley in 1772. The atomic number of oxygen is 8, and its electronic configuration is 1s2 2s2 2p4. It has six valence electrons. The atomic weight of oxygen is 15.9994 atomic mass units.\nOxygen belongs to period 2 and group 16 of the periodic table of elements. It is a gas at normal temperature and pressure. The symbol of oxygen is O. It belongs to the family of elements called chalcogens.

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Is carbon dioxide a pure substance?

Two or more pure substances can be mixed together to form a mixture. An example of a mixture of two compounds is alcohol and water. An example of a mixture of elements and compounds is air. The major components of air are hydrogen, oxygen, nitrogen and carbon dioxide. The substances in a mixture can be separated physically via such methods as filtration or chromatography.

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What is it like inside a sinkhole?

One common cause of sinkhole formation is the dissolution of minerals or weaker stone by groundwater. As water carries away particles of the material underground, it leaves a growing hole in the earth. Eventually, this becomes too large to support itself, resulting in a rapid collapse. Sinkholes can also occur when the water table drops suddenly, removing some of the pressure that was holding up the soil above and emptying underground caves and aquifers.\nArtificial sinkholes also exist, created when underground mines or other structures collapse. A sinkhole can also occur when surface constru..

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Does Pluto have seasons?

As Pluto moves away from the furthest point of its orbit, the south pole begins to tilt towards the sun, causing autumn in the northern hemisphere. As the south pole faces the sun and the planet moves towards the closest point on its orbit to the sun, the northern hemisphere experiences winter. As Pluto moves away from the closest point on its orbit to the sun, the northern hemisphere undergoes spring.

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What are the sources of electricity?

Electricity is a secondary source of energy because it cannot be extracted from the ground, like fossil fuels, or captured from moving phenomena, such as water or wind. Most electricity consumed in the United States has a fossil fuel as its source, according to the United States Environmental Protection Agency. Renewable resources, such as wind and solar, represent a small but growing percentage of electricity sources.Fossil fuelsFossil fuels occur naturally in the earth and are the remains of living organisms from the geological past. They include coal, oil and natural gas, which generate ele..

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What is the difference between CC and mL?

The centimeter is derived from the meter, and is exactly 1 percent of a meter. A cubic centimeter is exactly 0.0001 percent of a cubic meter. The mL is derived from the liter, which unlike a meter, is already a unit of volume. A mL is exactly 0.001 percent of a liter. When measuring a given volume of liquid with a ruler, it is most practical to determine the volume in CCs or cubic meters before converting it to liters or mLs.

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What is the function of dendrites?

Dendrites receive electrical messages from the axons of neurons. The messages are either excitatory or inhibitory. Excitatory signals cause the neuron to increase its overall activity and release excitatory neurotransmitters. Inhibitory signals cause the neuron to decrease its overall activity and release inhibitory signals.\nDendrites that receive these signals can communicate them to other neurons in order to cause action potentials and communication signals to propagate or to dissolve. Both types of signals are essential for a healthy nervous system.

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What stages represent the beginning and the end of the cell cycle?

The longest stage is metaphase, during which the cell's chromosomes are aligned along an imaginary line (the metaphase plate), which divides the cell into two halves. The following stage, anaphase, is the shortest portion of the cell division process. The time in between the five stages is called the interphase and represents the longest part of the cell cycle. During this time, the cell grows, its centrioles divide, and DNA is replicated.

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