Q: In plants, a high concentration of iaa inhibits what? Read this paragraph and choose the correct option from the provided answers: the bottom of the cell. In roots, a high concentration of IAA inhibits cell elongation. The effect slows growth on the lower side of the root, while cells develop normally on the upper side. IAA has the opposite effect in shoots, where a higher concentration at the lower side of the shoot stimulates cell expansion, causing the shoot to grow up. After the shoot or root begin to grow vertically, the amyloplasts return to their normal position. Other hypothesesinvolving the entire cell in the gravitropism effecthave been proposed to explain why some mutants that lack amyloplasts may still exhibit a weak gravitropic response. Choices: - Cell reproduction - same elongation - technology elongation - cell elongation A:
cell elongation
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Q: What describes how close an estimate is to a known standard? Read this paragraph and choose the correct option from the provided answers: Accuracy describes how close an estimate is to a known standard. Choices: - diversity - frequency - precision - accuracy A:
accuracy
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Q: Earth's magnetic north and south poles are not the same as what? Read this paragraph and choose the correct option from the provided answers: Earth has north and south magnetic poles like a bar magnet. Earth's magnetic poles are not the same as the geographic poles. Choices: - equatorial planes - geographic currents - geographic hemispheres - geographic poles A:
geographic poles
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Q: Scientists around the world study speciation, documenting observations both of living organisms and those found in the fossil record. as their ideas take shape and as research reveals new details about how life evolves, they develop models to help explain what? Read this paragraph and choose the correct option from the provided answers: Varying Rates of Speciation Scientists around the world study speciation, documenting observations both of living organisms and those found in the fossil record. As their ideas take shape and as research reveals new details about how life evolves, they develop models to help explain rates of speciation. In terms of how quickly speciation occurs, two patterns are currently observed: gradual speciation model and punctuated equilibrium model. In the gradual speciation model, species diverge gradually over time in small steps. In the punctuated equilibrium model, a new species undergoes changes quickly from the parent species, and then remains largely unchanged for long periods of time afterward (Figure 18.23). This early change model is called punctuated equilibrium, because it begins with a punctuated or periodic change and then remains in balance afterward. While punctuated equilibrium suggests a faster tempo, it does not necessarily exclude gradualism. Choices: - spontaneous mutation - creation theory - food chains - rates of speciation A:
rates of speciation
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