Answer the following question given this paragraph: The only difference between each nucleotide is the identity of the base. There are only four possible bases that make up each DNA nucleotide: adenine (A), guanine (G), thymine (T), and cytosine (C). Q: There are only four possible bases that make up each dna nucleotide: adenine, guanine, thymine, and? Choices: - taurine - phenylalanine - guarine - cytosine A:
cytosine
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Answer the following question given this paragraph: Diseases One of the most talked about diseases is skin cancer. Cancer is a broad term that describes diseases caused by abnormal cells in the body dividing uncontrollably. Most cancers are identified by the organ or tissue in which the cancer originates. One common form of cancer is skin cancer. The Skin Cancer Foundation reports that one in five Americans will experience some type of skin cancer in their lifetime. The degradation of the ozone layer in the atmosphere and the resulting increase in exposure to UV radiation has contributed to its rise. Overexposure to UV radiation damages DNA, which can lead to the formation of cancerous lesions. Although melanin offers some protection against DNA damage from the sun, often it is not enough. The fact that cancers can also occur on areas of the body that are normally not exposed to UV radiation suggests that there are additional factors that can lead to cancerous lesions. In general, cancers result from an accumulation of DNA mutations. These mutations can result in cell populations that do not die when they should and uncontrolled cell proliferation that leads to tumors. Although many tumors are benign (harmless), some produce cells that can mobilize and establish tumors in other organs of the body; this process is referred to as metastasis. Cancers are characterized by their ability to metastasize. Q: What term describes diseases caused by abnormal cells in the body dividing uncontrollably? Choices: - eczema - diabetes - radiation - cancer A:
cancer
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Answer the following question given this paragraph: To see an animation of the lifecycle of a fern and to test your knowledge, go to the website (http://openstaxcollege. org/ l/fern_life_cycle) . Most ferns produce the same type of spores and are therefore homosporous. The diploid sporophyte is the most conspicuous stage of the lifecycle. On the underside of its mature fronds, sori (singular, sorus) form as small clusters where sporangia develop (Figure 25.23). Q: Most ferns produce the same type of spores and are therefore called what? Choices: - seeds - sporozoans - heterosporous - homosporous A:
homosporous
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Answer the following question given this paragraph: A friend whispers to you in class in a voice so soft that you have to lean very close to hear what he's saying. Later that day, your friend shouts to you across the football field. Now his voice is loud enough for you to hear him clearly even though he's many meters away. Obviously, sounds can vary in loudness. Loudness refers to how loud or soft a sound seems to a listener. The loudness of sound is determined, in turn, by the intensity of sound. Intensity is a measure of the amount of energy in sound waves. The unit of intensity is the decibel (dB) . Q: What is the measure of the amount of energy found in sound waves? Choices: - decibels - density - frequency - intensity A:
intensity
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