________ are donut-shaped muscles that act as doors to let material in or out.
A. Sphincters
B. Intercalated discs
C. Aponeuroses
D. Primary movers
Answer: A
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Predict the effect of fluid loss through vomiting or diarrhea on juxtaglomerular cell activity
A) Renin would be released. B) Aldosterone levels would fall. C) ADH would be released. D) Renin levels would fall.
The ejaculatory duct is formed by the
A. ampulla and the proximal portion of the seminal vesicle. B. ductus deferens and the ducts of the prostate gland. C. ampulla and the distal portions of the bulbourethral glands. D. ductus deferens and the ducts of the prostate gland and bulbourethral glands. E. ampulla and the prostatic urethra.
Which of the following is NOT a function of estrogen during pregnancy?
A. stimulation of myometrial growth B. maintenance of the endometrium C. stimulation of prolactin secretion D. stimulation of breast development E. stimulation of milk synthesis
During inspiration, intra-alveolar pressure moves to:
1.756 mm Hg. 2.760 mm Hg. 3.764 mm Hg. 4.0 mm Hg.