What does the first heart sound signal the onset of?

a. atrial systole
b. atrial diastole
c. ventricular systole
d. ventricular diastole
e. firing of the SA node


c

Anatomy & Physiology

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Anatomy & Physiology

Which of the following statements concerning the masseter muscle is correct?

A. It is the most superficial muscle of facial expression. B. It originates from the zygomatic arch. C. It inserts on the medial surface of the mandible's angle. D. It depresses the mandible during jaw movement.

Anatomy & Physiology

The medial concavity of the kidney is called the ________, which admits the renal nerves, blood vessels, lymphatic vessels, and ureter.

A. cortex B. corpuscle C. capsule D. hilum E. medulla

Anatomy & Physiology

A(n) ________ is a localized elevation of the skin often accompanied by itching.

A. erosion B. wheal C. pustule D. macule

Anatomy & Physiology