The heart valves open and close due to
a. attachment to the heart muscle.
b. a pressure difference on the two sides of the valve.
c. Na+ and K+ fluxes during ventricular depolarization.
d. turbulent flow in the atria and ventricles.
e. none of these answers.
B
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Severing the sensory fibers from the lungs would result in all of the following except
A) less inhibition of the inspiratory center during forced breathing. B) a drop in tidal volume. C) potential damage to the lungs due to overinflation. D) a disappearance of the Hering-Breuer reflexes. E) less stimulation of the expiratory center during forced breathing.
Which connective tissue specializes in storage of fat?
What will be an ideal response?
Which of the following statements is false?
A. The seminal vesicles open into the membranous urethra. B. The prostate gland surrounds the prostatic urethra and ejaculatory ducts. C. The bulbourethral glands enter the spongy urethra at the base of the penis. D. The prostate gland contains smooth muscle partitions covered with columnar epithelium. E. The seminal vesicles are sac-shaped glands located next to the ampullae of the ductus deferentia.
Matching
A) Cystic fibrosis B) Achondroplasia C) Albinism D) Tay-Sachs disease E) Huntington's disease 5) Lack of skin pigmentation. 6) Rare type of dwarfism resulting from an impaired ability of the fetus to lengthen long bones by endochondrial ossification. 7) An unremitting, fatal nervous system disease involving degeneration of the basal nuclei. 8) A condition of drier excessively sticky mucus production. 9) A disorder of brain lipid metabolism.