Flattened fibrous sacs that reduce friction between adjacent structures are called:

• A. Bursae
• B. Tendons
• C. Ligaments
• D. Menisci

Answer: (A)

Verified step by step guidance

1. Step 1: Understand the function described in the question. The problem mentions 'flattened fibrous sacs that reduce friction between adjacent structures.' This indicates a structure that facilitates smooth movement between tissues, such as muscles, tendons, and bones.
2. Step 2: Review the definition of 'bursae.' Bursae are small, flattened sacs lined with synovial membrane and filled with synovial fluid. Their primary function is to reduce friction and cushion pressure points between moving parts, such as tendons and bones.
3. Step 3: Compare the function of bursae with the other options provided: Tendons connect muscles to bones and transmit force during movement; ligaments connect bones to other bones and provide joint stability; menisci are crescent-shaped cartilage structures that provide cushioning and stability in joints like the knee.
4. Step 4: Eliminate options that do not match the description in the question. Tendons, ligaments, and menisci do not primarily function to reduce friction between adjacent structures; their roles are more related to connection and support.
5. Step 5: Conclude that the correct answer is 'Bursae,' as they are specifically designed to reduce friction between adjacent structures, aligning with the description provided in the question.