1. Which structure does NOT increase the speed of impulse transmission along the axon? A Large diameter axon B Dendrite C Myelin sheath D Schwann cell 2. The effect of a hormone X, on the twigs of plant is shown in the diagram below. Control With hormone X Figure 1 Which statements are TRUE about hormone X? I X is ethylene, which causes abscission of leaf. II The effects of X could be counteracted by auxin. III X is abscisic acid, which promotes the senescence of leaves. IV X is a type of gas with $CH_2=CH_2$ formula, which defoliates leaves and beans of the plant. A I and III B I and IV C II and III D II and IV
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Dendrites receive signals from other neurons and transmit them towards the cell body, but they do not play a direct role in increasing the speed of impulse transmission. For the second question, based on the given information, we can conclude that statement I is Show more…
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