At puberty, an adolescent female body changes in both structure and function of several organ systems, primarily under the influence of changing concentrations of estrogens and other steroid hormones. How can one hormone, such as estrogen, mediate so many
effects?
A) Estrogen is produced in very large concentration by nearly every tissue of the body.
B) Each cell responds in the same way when steroids bind to the cell surface.
C) Estrogen is kept away from the surface of any cells not able to bind it at the surface.
D) Estrogen binds to specific receptors inside many kinds of cells, each with different responses.
E) Cells metabolize steroids in different ways, producing by-products that stimulate tRNA production.
Answer: D
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