Figure 16-20 Shows the Pathway Through Which Nitric Oxide (NO)

question 39

Multiple Choice

Figure 16-20 shows the pathway through which nitric oxide (NO) triggers smooth muscle relaxation in a blood vessel wall.Which of the following situations would lead to relaxation of the smooth muscle cells in the absence of acetylcholine? Figure 16-20

• A)a smooth muscle cell that has a defect in guanylyl cyclase such that it cannot bind NO
• B)a muscle cell that has a defect in guanylyl cyclase such that it constitutively converts GTP to cyclic GMP
• C)a muscle cell that has cyclic GMP phosphodiesterase constitutively active
• D)a drug that blocks an enzyme involved in the metabolic pathway from arginine to NO

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Definitions:

Periosteum

The periosteum is a dense layer of vascular connective tissue enveloping the bones except at the surfaces of the joints.

Nervous System

The network of nerve cells and fibers that transmits nerve impulses between parts of the body, coordinating and controlling bodily functions and activities.

Reflex Arc

The neural pathway that mediates a reflex action involving sensory nerves, a central nervous system integration center, and motor nerves.

Nervous System

An extensive network of specialized cells and tissues responsible for controlling and coordinating body activities by transmitting electrical and chemical signals throughout the body.