Chemical communication can also occur locally between neighboring cells, or between individuals, through the release of pheromones, coordinating social interactions. The figure below shows epithelial cells in the lungs
When the epithelial monolayer is
damaged by mechanical injury, breaching of the barrier allows epithelial cells to sense injury
and initiate a repair pathway. When the ligand binds its receptor, it triggers a signaling
cascade that stimulates cell division. The ligand (heregulin) is produced by these same cells
that produce the receptor, but is released only on the apical side of the epithelium.
Mechanical damage allows molecules from apical and basal surfaces to mix.
The signaling is best described as:
A. paracrine.
B. autocrine.
C. endocrine.
D. synaptic.
B
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A seed that lands in the forest soil is homozygous mutant for the CONSTANS (CO) gene, and as a result does not produce any functional CONSTANS protein. What do you predict will happen during the development of this seed?
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Which of the following explains why fungi are such efficient decomposers, allowing them to undergo rapid and extensive growth?
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Which of the following scenarios represents a situation where a suspected disease-causing microbe would not be consistent with one or more of Koch’s postulates?
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