[Q]: I have a new situation: Two researches studied living organisms, Joe studied eukaryotes, while Bill studied prokaryotes. They were fascinated by genetic variation. But I can use this background: Prokaryotes have a different way to increase genetic variation. It's called genetic transfer or bacterial conjugation . It can occur in two ways. One way is when cells "grab" stray pieces of DNA from their environment. The other way is when cells directly exchange DNA (usually plasmids) with other cells. For example, as shown in Figure below , the donor cell makes a structure called an F pilus , or sex pilus. The F pilus attaches one cell to another cell. The membranes of the two cells merge and genetic material, usually a plasmid , moves into the recipient cell. Genetic transfer makes bacteria very useful in biotechnology. It can be used to create bacterial cells that carry new genes. What is an answer for this question: Which researcher observed fewer cells directly exchange DNA (usually plasmids) with other cells?
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[A]: Joe

[Q]: I have a new situation: Jake and Todd used different farming methods to produce their crops. Jake always tills his land, while Todd uses he no-tillage method. But I can use this background: The benefits provided by no-tillage to predators may lead to larger predator populations, which is a good way to control pests (biological control), but also can facilitate predation of the crop itself. In corn crops, for instance, predation by caterpillars can be higher in no-till than in conventional tillage fields.In places with rigorous winter, untilled soil can take longer to warm and dry in spring, which may delay planting to less ideal dates. Another factor to be considered is that organic residue from the prior year's crops lying on the surface of untilled fields can provide a favorable environment to pathogens, helping to increase the risk of transmitting diseases to the future crop. And because no-till farming provides good environment for pathogens, insects and weeds, it can lead farmers to a more intensive use of chemicals for pest control. Other disadvantages of no-till include underground rot, low soil temperatures and high moisture.Based on the balance of these factors, and because each farm has different problems, agroecologists will not attest that only no-till or complete tillage is the right way of farming. Yet, these are not the only possible choices regarding soil preparation, since there are intermediate practices such as strip-till, mulch-till and ridge-till, all of them just as no-till categorized as conservation tillage. Agroecologists, then, will evaluate the need of different practices for the contexts in which each farm is inserted. What is an answer for this question: Which farmer didn't provide a good environment for pathogens?
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[A]: Jake

[Q]: I have a new situation: Two groups of soldiers started different training programs. Blue group did weight training for 3 months, while Brown group ran 3 miles a day for three months. The Captain observed different results on each group. But I can use this background: In exercises such as weight lifting, skeletal muscle contracts against a resisting force (see Figure below ). Using skeletal muscle in this way increases its size and strength. In exercises such as running, the cardiac muscle contracts faster and the heart pumps more blood. Using cardiac muscle in this way increases its strength and efficiency. Continued exercise is necessary to maintain bigger, stronger muscles. If you don't use a muscle, it will get smaller and weakerso use it or lose it. What is an answer for this question: Which group had their cardiac muscles contract faster while training?
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[A]: Brown

[Q]: I have a new situation: Mike was reading about climate change. The author compared two different time periods, era A and era B. Era A was set in the present day. But era B was set in the year 2040. Mike was surprised to find how Arctic area would change in the coming years. But I can use this background: Reduction of the area of Arctic sea ice reduces the planet's average albedo, possibly resulting in global warming in a positive feedback mechanism. Research shows that the Arctic may become ice free in the summer for the first time in human history within by 2040. Estimates vary for when the last time the Arctic was ice free: 65 million years ago when fossils indicate that plants existed there to as few as 5,500 years ago; ice and ocean cores going back 8000 years to the last warm period or 125,000 during the last intraglacial period.Warming temperatures in the Arctic may cause large amounts of fresh meltwater to enter the north Atlantic, possibly disrupting global ocean current patterns. Potentially severe changes in the Earth's climate might then ensue.As the extent of sea ice diminishes and sea level rises, the effect of storms such as the Great Arctic Cyclone of 2012 on open water increases, as does possible salt-water damage to vegetation on shore at locations such as the Mackenzie's river delta as stronger storm surges become more likely.Global warming has increased encounters between polar bears and humans. Reduced sea ice due to melting is causing polar bears to search for new sources of food. Beginning in December 2018 and coming to an apex in February 2019, a mass invasion of polar bears into the archipelago of Novaya Zemlya caused local authorities to declare a state of emergency. Dozens of polar bears were seen entering homes and public buildings and inhabited areas. What is an answer for this question: Would era B see less or more ice in the Arctic than era A?
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[A]:
less