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:

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A primitive reflex in newborns which causes them to turn their head to one side, automatically raising the arm and leg on that side, and lowering them on the opposite.

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Soap with a pH level above 7, which can neutralize acid and is often considered gentler on the skin.

Circumcision Pain

The discomfort and pain experienced as a result of the surgical removal of the foreskin from the penis.

Umbilical Cord

A flexible, tube-like structure connecting a fetus to the placenta, supplying oxygen and nutrients while removing waste products.