[Q]: Please answer correctly the following question related to the paragraph below. Which researcher learned more about acetogenesis? Bob and Andy are two microbiologists. They are studying bacteria: Bob studies nitrogen fixating bacteria, while Andy studies non-respiratory and facultative anaerobes. Hint: In many ways, bacterial metabolism provides traits that are useful for ecological stability and for human society. One example is that some bacteria have the ability to fix nitrogen gas using the enzyme nitrogenase. This environmentally important trait can be found in bacteria of most metabolic types listed above. This leads to the ecologically important processes of denitrification, sulfate reduction, and acetogenesis, respectively. Bacterial metabolic processes are also important in biological responses to pollution; for example, sulfate-reducing bacteria are largely responsible for the production of the highly toxic forms of mercury (methyl- and dimethylmercury) in the environment. Non-respiratory anaerobes use fermentation to generate energy and reducing power, secreting metabolic by-products (such as ethanol in brewing) as waste. Facultative anaerobes can switch between fermentation and different terminal electron acceptors depending on the environmental conditions in which they find themselves.
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[A]: Bob

[Q]: Please answer correctly the following question related to the paragraph below. Which planet has a higher temperature? Space explorers, that launched from Earth, just encountered a new planet several light years away. This planet is almost an exact copy of Earth, but it is currently uninhabited by intelligent life. Upon landing, the explorers name the planet Caprica and begin learning as much as they can. They discover that the species on this Caprica are nearly all the same as on Earth, and even most of the topography looks the same. However, the main difference is that humans never evolved here. For this reason, there are no cities or cars or factories to burn up fossil fuels. Hint: When humans dig up and use fossil fuels, we have an impact on the carbon cycle ( Figure below ). This carbon is not recycled until it is used by humans. The burning of fossil fuels releases more carbon dioxide into the atmosphere than is used by photosynthesis. So, there is more carbon dioxide entering the atmosphere than is coming out of it. Carbon dioxide is known as a greenhouse gas , since it lets in light energy but does not let heat escape, much like the panes of a greenhouse. The increase of greenhouse gasses in the atmosphere is contributing to a global rise in Earth's temperature, known as global warming or global climate change.
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[A]: Earth

[Q]: Please answer correctly the following question related to the paragraph below. Would case A see higher or lower air density than case B? John wanted to see how he would fare in high altitude compared to ground-level. So, he first measured his responses in ground-level. He labeled this part of the study as case A. Then he board on an airplane to reach high altitude, and measured his responses there. He labeled this part of the study as case B. Now, John knows how he needs to prepare for a high altitude hiking. Hint: As shown here, pressure decreases to less than 25% of ground-level atmospheric pressure when we get to an altitude of about six miles. Since this is a common cruising altitude for commercial airplanes, pressurized cabins are needed for the comfort and survival of the passengers. This is because the density of the air decreases along with the decreasing air pressure, so there is less oxygen in a breath of air. You've probably noticed this effect in high-mountain areas, as it often feels harder to breath.
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[A]: higher

[Q]: Please answer correctly the following question related to the paragraph below. Will there be more or less micronutrients on Jerry's crops? Jerry and Gary each live in separate cities, but both run equally sized farms that grow the same produce. The cities they live in have very similar environments with the only difference being that the CO2 levels in Jerry's town are elevated, and in Gary's they are not. Jerry and Gary regularly talk on the phone and compare notes with each other since their farms are so similar. Hint: Plants can grow as much as 50 percent faster in concentrations of 1,000 ppm CO2 when compared with ambient conditions, though this assumes no change in climate and no limitation on other nutrients. Elevated CO2 levels cause increased growth reflected in the harvestable yield of crops, with wheat, rice and soybean all showing increases in yield of 1214% under elevated CO2 in FACE experiments.Increased atmospheric CO2 concentrations result in fewer stomata developing on plants which leads to reduced water usage and increased water-use efficiency. Studies using FACE have shown that CO2 enrichment leads to decreased concentrations of micronutrients in crop plants. This may have knock-on effects on other parts of ecosystems as herbivores will need to eat more food to gain the same amount of protein.The concentration of secondary metabolites such as phenylpropanoids and flavonoids
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[A]:
less