What causes closure of the foramen ovale at birth?
A. Higher pressure in the left atrium, which causes interatrial septum flaps to close
B. Rapid myocardial tissue growth stimulated by pregnancy hormones
C. A rise in fetal oxygen levels, which triggers growth of the epithelial lining
D. An increase in endothelial mucous production, which forms a plug
E. Migration of connective tissue from the right atrioventricular valve
A
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Which of the following muscles compresses the abdomen?
A) diaphragm and intercostals B) external oblique and latissimus dorsi C) rectus abdominis and pectoralis major D) transverse abdominis E) external oblique, rectus abdominis, and transverse abdominis
At an intercalated disc,
A) the cell membranes of two cardiac muscle fibers are completely separated by a synapse. B) the myofibrils are loosely attached to the membrane of the disc. C) t-tubules unite the membranes of the adjoining cells. D) two cardiac muscle cells are connected by gap junctions. E) All of the answers are correct.
The study of the heart, blood, and blood vessels is which of the following approaches?
A) systemic anatomy B) regional anatomy C) developmental anatomy D) comparative anatomy E) gross anatomy
An organ system that protects vital organs, produces blood cells, and stores minerals is the ________ system
A. cardiovascular B. skeletal C. lymphatic D. integumentary