Use This Information to Respond to the Following Questions

question 13

Multiple Choice

Use this information to respond to the following questions.
Humans have receptors for two kinds of beta adrenergic compounds such as catecholamines to control cardiac muscle contractions. Some are beta 1 receptors that promote increased heart rate. Other drugs, called beta blockers, slow heart rate. Smooth muscle cells, however, have beta 2 receptors, which mediate muscle relaxation. Blockers of these effects are sometimes used to treat asthma.
-The description above illustrates which of the following?

• A) Just because a drug acts on one type of receptor does not mean that it will act on another type.
• B) Beta blockers can be used effectively on any type of muscle.
• C) Beta adrenergic receptors must be in the cytosol if they are going to influence contraction and relaxation.
• D) The chemical structures of the beta 1 and beta 2 receptors must have the same active sites.

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Definitions:

Br2

Bromine, a diatomic molecule consisting of two bromine atoms, used as a reagent in various chemical reactions.

Dimethylsulfide

An organic sulfur compound with the formula (CH3)2S, known for its distinctive smell reminiscent of the ocean or cooked corn.

Alkene

A hydrocarbon that contains at least one carbon-carbon double bond in its structure.

OsO4

Osmium tetroxide, a compound used in organic chemistry to add oxygen atoms to double bonds in alkenes.