Why do some individual hormones have multiple effects on different target tissues?
A) Second messengers trigger cascade or amplification effects. B) Many different cells in different tissues have specific receptors for the hormone. C) Only a small amount of the hormone is required for its effect. D) Gene transcription is altered.
Suppose that hormone A binds to intracellular receptors in its target tissue. Also suppose that as a result of hormone A, the target tissue is now sensitive to or responsive to hormone B. What was the action of hormone A?
A) to decrease mRNA for hormone A receptors B) to increase cyclic AMP levels which activated receptors for hormone B C) to increase receptor sites for hormone B D) to increase receptor sits for hormone A