Which of the Following Reduces Friction in Movable Joints, Such

Question

Which of the following reduces friction in movable joints, such as the knee?
A) sebum
B) serous fluid
C) synovial fluid
D) sweat
E) keratin

Accepted Answer

Synovial fluid reduces friction in movable joints, such as the knee. Sebum is produced by sebaceous glands in the skin and helps waterproof and moisturize the skin. Serous fluid is a thin, watery fluid that helps reduce friction between internal organs. Sweat helps regulate body temperature by evaporative cooling. Keratin is a protein found in hair, nails, and skin that provides strength and protects against damage.