BIOLOGICAL BASES OF BEHAVIOR
THE NERVOUS AND ENDOCRINE SYSTEMS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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composed of glycoproteins.
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active on a single target tissue.
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signalling molecules that act on receptor molecules.
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transported around the organism by a circulating fluid.
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Detailed explanation-1: -A cell within a multicellular organism may need to signal to other cells that are at various distances from the original cell (Figure 1). Not all cells are affected by the same signals.
Detailed explanation-2: -Answer and Explanation: Cell signaling is similar in plants and animals in that it uses small molecules that move from the cell that is producing the signal to those that are receiving it. These molecules then initiate events that alter gene expression in the target cell to produce an appropriate response.
Detailed explanation-3: -In contrast to hormones, some signaling molecules act locally to affect the behavior of nearby cells. In paracrine signaling, a molecule released by one cell acts on neighboring target cells. An example is provided by the action of neurotransmitters in carrying signals between nerve cells at a synapse.