Question

the reduction of friction between the parietal and visceral surfaces of an internal cavity is the function of

○ synovial membranes.

○ mucous membranes.

○ serous membranes.

○ the lamina propria.

○ cutaneous membranes.

Explanation:

1. Recall the functions of different membranes:

• Synovial membranes: Line joint cavities and secrete synovial fluid for joint lubrication, not for internal body cavities' parietal - visceral surfaces.
• Mucous membranes: Line body cavities open to the exterior (like digestive, respiratory tracts) and secrete mucus, not for reducing friction between parietal and visceral surfaces of internal closed cavities.
• Serous membranes: Line internal body cavities (like pleural, peritoneal, pericardial cavities). They have parietal (lining cavity wall) and visceral (covering organ) layers and secrete serous fluid, which reduces friction between these two surfaces.
• Lamina propria: Is a connective tissue layer under mucous membranes, not related to reducing friction between parietal and visceral surfaces of internal cavities.
• Cutaneous membranes: Are the skin, which is the outer covering of the body, not related to internal body cavities.

Answer:

C. serous membranes.