A valve-like structure around a body opening and passage that controls the movement of substances into and out of the passages is called a(n) ________. 

Fill in the blank(s) with the appropriate word(s).

sphincter
Sphincters control the movement of substances into and out of passages.

Health Professions

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If the fire is beyond the ability of hand-lines to control, master streams can be utilized to attack the fire. What is this mode of attack known as?

A) Blitzkrieg mode B) Offensive mode C) Defensive mode D) Defensive/offensive mode

Health Professions

Using an ICD-9-CM code book, select the appropriate code(s) for the diagnostic statements given in the following questions

Abnormal placenta found by ultrasound

Health Professions