[Q]: You are given a new situation: Greg is studying the environmental impact of agriculture. He noticed that in his own state a lake near agricultural lands has been declared as a dead zone. For his study Greg labeled this zone as zone A. Then he found near a national park in his state a lake is not declared as a dead zone. To further his study he labeled this zone as zone B. and a hint : Rain dissolves fertilizer in the soil. Runoff carries it away. The fertilizer ends up in bodies of water, from ponds to oceans. Nitrogen is a fertilizer in the water. Since there is a lot of nitrogen, it causes algae to grow out of control. Pictured below is a pond covered with algae ( Figure below ). Algae use up carbon dioxide in the water. After the algae die, decomposers break down the dead tissue. The decomposers use up all the oxygen in the water. This creates a dead zone. A dead zone is an area in a body of water where nothing grows because there is too little oxygen. There is a large dead zone in the Gulf of Mexico ( Figure below ). The U.S. states outlined on the map have rivers that drain into the Gulf of Mexico. The rivers drain vast agricultural lands. The water carries fertilizer from these areas into the Gulf. Please answer this question : In which zone more organisms would grow, zone A or zone B?
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[A]: zone B

[Q]: You are given a new situation: Jim and Robert are identical twins both getting their yearly physical check ups at the doctor's office. They are trying to figure out if they are at risk for any future health problems. Both of them consume the same diet and exercise the same amount, and were both raised in the exact same environment. But, Jim has smoked tobacco frequently for several years and Robert has never smoked tobacco in his life. and a hint : Many different chemical substances cause cancer. Dozens of chemicals in tobacco smoke, including nicotine, have been shown to cause cancer ( Figure below ). In fact, tobacco smoke is one of the main sources of chemical carcinogens. Smoking tobacco increases the risk of cancer of the lung, mouth, throat, and bladder. Using smokeless tobacco can also cause cancer. Other chemicals that cause cancer include asbestos, formaldehyde, benzene, cadmium, and nickel. Please answer this question : Who is at a higher risk for getting mouth cancer in the future?
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[A]: Jim

[Q]: You are given a new situation: Two brothers went to the doctor's office for a medical exam and blood tests. Dan found out he is healthy and had normal blood cholesterol and calcium levels. Ben however, was told that he had a disease called hypercalcaemia and had to start a treatment for that. and a hint : Excess intake of calcium may cause hypercalcaemia. However, because calcium is absorbed rather inefficiently by the intestines, high serum calcium is more likely caused by excessive secretion of parathyroid hormone (PTH) or possibly by excessive intake of vitamin D, both which facilitate calcium absorption. It may also be due to bone destruction that occurs when tumours metastasize within bone. All these conditions result in excess calcium salts being deposited in the heart, blood vessels, or kidneys. Symptoms include anorexia, nausea, vomiting, memory loss, confusion, muscle weakness, increased urination, dehydration, and metabolic bone disease. Chronic hypercalcaemia typically leads to calcification of soft tissue and its serious consequences: for example, calcification can cause loss of elasticity of vascular walls and disruption of laminar blood flowand thence to plaque rupture and thrombosis. Conversely, inadequate calcium or vitamin D intakes may result in hypocalcaemia, often caused also by inadequate secretion of parathyroid hormone or defective PTH receptors in cells. Symptoms include neuromuscular excitability, which potentially causes tetany and disruption of conductivity in cardiac tissue. Please answer this question : Which brother experienced less nausea?
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[A]: Dan

[Q]: You are given a new situation: Bess and Dee were two entomologists. they were studying ants. Dee liked to learn more about leaf cutter ants, while Bess learned all she could about all other ants. and a hint : Most ants are generalist predators, scavengers, and indirect herbivores, but a few have evolved specialised ways of obtaining nutrition. It is believed that many ant species that engage in indirect herbivory rely on specialized symbiosis with their gut microbes to upgrade the nutritional value of the food they collect and allow them to survive in nitrogen poor regions, such as rainforest canopies. Leafcutter ants (Atta and Acromyrmex) feed exclusively on a fungus that grows only within their colonies. They continually collect leaves which are taken to the colony, cut into tiny pieces and placed in fungal gardens. Ergates specialise in related tasks according to their sizes. The largest ants cut stalks, smaller workers chew the leaves and the smallest tend the fungus. Leafcutter ants are sensitive enough to recognise the reaction of the fungus to different plant material, apparently detecting chemical signals from the fungus. If a particular type of leaf is found to be toxic to the fungus, the colony will no longer collect it. The ants feed on structures produced by the fungi called gongylidia. Symbiotic bacteria on the exterior surface of the ants produce antibiotics that kill bacteria introduced into the nest that may harm the fungi. Please answer this question : Which person read more about ants which build fungal gardens?
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[A]:
Dee