Which of the following body systems is located entirely within a single body cavity?

• A. Digestive system
• B. Urinary system
• C. Nervous system
• D. Respiratory system

Answer: (B)

Verified step by step guidance

1. Step 1: Begin by understanding the concept of body cavities. Body cavities are spaces within the body that house and protect internal organs. The major body cavities include the cranial cavity, thoracic cavity, abdominal cavity, and pelvic cavity.
2. Step 2: Analyze the location of each body system mentioned in the problem. For example, the digestive system spans multiple cavities, including the thoracic cavity (esophagus) and abdominal cavity (stomach, intestines).
3. Step 3: Consider the urinary system. The urinary system, which includes the kidneys, ureters, bladder, and urethra, is primarily located within the abdominal and pelvic cavities, making it confined to a single cavity.
4. Step 4: Evaluate the nervous system. The nervous system is distributed throughout the body, with the brain in the cranial cavity and the spinal cord in the vertebral cavity, so it spans multiple cavities.
5. Step 5: Assess the respiratory system. The respiratory system includes the lungs and trachea, which are located in the thoracic cavity, but it also involves structures like the nasal cavity, which is outside the thoracic cavity. Therefore, it spans multiple cavities.