[Q]: Two different rivers were stocked with adult fish. Red river had a lower fish population because the fish had hardly reproduced naturally. Black river had doubled it's fish population in two years because they reproduced naturally. Which of the two rivers had more fish lay eggs outside of the body? Hint: Fish reproduce sexually. They lay eggs that can be fertilized either inside or outside of the body. In most fish, the eggs develop outside of the mother's body. In the majority of these species, fertilization also takes place outside the mother's body. The male and female fish release their gametes into the surrounding water, where fertilization occurs. Female fish release very high numbers of eggs to increase the chances of fertilization.
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[A]: Black

[Q]: Two students from the same class, studies different types of animals. Bill studied predators, while John studied grazers. Which student studied more about wolves? Hint: Predators play an important role in an ecosystem. For example, if they did not exist, then a single species could become dominant over others. Grazers on a grassland keep grass from growing out of control. Predators can be keystone species . These are species that can have a large effect on the balance of organisms in an ecosystem. For example, if all of the wolves are removed from a population, then the population of deer or rabbits may increase. If there are too many deer, then they may decrease the amount of plants or grasses in the ecosystem. Decreased levels of producers may then have a detrimental effect on the whole ecosystem. In this example, the wolves would be a keystone species.
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[A]: Bill

[Q]: Two bears are living in the same forest. One bear, named Teddy, often runs and is active in its daily life. The other bear, Fluffy, is lazy and hardly moves at all. Their levels of fitness are very different with Teddy having a much higher overall fitness level than Fluffy. Is Fluffy more or less likely than Teddy to pass his genes on to the next generation of bears? Hint: All of these animal behaviors are important. They help the animals get food for energy, make sure their young survive, or ensure that they, themselves, survive. Behaviors that help animals or their young survive, increase the animals' fitness. Animals with higher fitness have a better chance of passing their genes on to the next generation. If genes control behaviors that increase fitness, the behaviors become more common in the species. This occurs through the process of evolution by natural selection.
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[A]: less

[Q]: Robert studied two groups of patients. Group O had mild allergy symptoms, while group R displayed severe allergy symptoms. Which group may require an injection of the hormone epinephrine? Hint: Allergy symptoms can range from mild to severe. Mild symptoms might include itchy eyes, sneezing, and a runny nose. Severe symptoms can cause difficulty breathing, which may be life threatening. Keep in mind that it is the immune system and not the allergen that causes the allergy symptoms. Allergy symptoms can be treated with medications such as antihistamines. Severe allergic reactions may require an injection of the hormone epinephrine. These treatments lessen or counter the immune system's response.
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[A]:
group R