Kaplan Nursing Entrance Exam Practice 2026 – Comprehensive Prep

The primary role of the rectum in the human body is to store fecal matter until it is excreted. The rectum, which is the final section of the large intestine, acts as a temporary reservoir for waste material. When the rectum fills with fecal matter, stretch receptors are activated, signaling the need for a bowel movement. This storage function is crucial for the coordinated process of defecation, allowing the body to control the timing and location of waste elimination.

The other options do not align with the rectum's primary function. Nutrient absorption occurs mainly in the small intestine, and while the rectum may absorb some water, it is not its primary role. The rectum does not play a role in regulating body temperature; that function is handled by various mechanisms in the body, primarily through the skin and hypothalamus. The rectum is also not involved in filtering blood, as this function is typically performed by the kidneys.