_____ Is a Circular Muscle That Acts as a Valve

question 71

Multiple Choice

_____ is a circular muscle that acts as a valve, opening and closing to allow the gastric contents to move throughout the GI tract.

• A) Connective tissue
• B) The lumen
• C) A sphincter
• D) The rectum

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Definitions:

Visual Angle

A measure of the size an object appears to an observer, determined by the object's actual size and its distance from the observer.

Figure-ground

A perceptual phenomenon where the focus is on a central object (figure) while the rest (ground) forms a background, showcasing how our perception separates visual stimuli.

Monocular Cue

A visual signal that allows for depth perception and estimation of an object's distance using just one eye.

Superposition

A principle in physics that for any two overlapping waves, the resulting wave is obtained by adding the amplitudes of the individual waves at each point.