(Q).
Q: What plant hormone allows plants to curve in a specific direction? Read this paragraph and choose the correct option from the provided answers: Plants may not be able to move to another location, but they are able to change how they grow in response to their environment. Growth toward or away from a stimulus is known as a tropism ( Table below ). Auxins, a class of plant hormones, allow plants to curve in specific directions as they grow. The auxin moves to one side of the stem, where it starts a chain of events that cause rapid cell growth on just that one side of the stem. With one side of the stem growing faster than the other, the plant begins to bend. Choices: - peptides - pheremone - apoptosis - auxin A:
(A).
auxin

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Q: Potassium is a soft, silvery metal that ignites explosively in what? Read this paragraph and choose the correct option from the provided answers: Potassium is a soft, silvery metal that ignites explosively in water. It easily loses its one valence electron to form positive potassium ions (K + ), which are needed by all living cells. Potassium is so important for plants that it is found in almost all fertilizers, like the one shown here. Potassium is abundant in Earth's crust in minerals such as feldspar. Choices: - air - cold - acid - water A:
(A).
water

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Q: Vertebrates differ from invertebrates because they lack this? Read this paragraph and choose the correct option from the provided answers: The first vertebrates evolved about 550 million years ago. The evolution of amphibians, reptiles, mammals, and birds occurred over the next 400 million years. The first vertebrates were ectotherms; endothermy evolved later. Modern fish, amphibians, and reptiles are ectotherms. Modern birds and mammals are endotherms. Choices: - legs - head - neck - backbone or a spinal column A:
(A).
backbone or a spinal column