Final answer:
Articular cartilage is the tissue that covers the epiphysis of bones, reducing friction in joints by providing a smooth gliding surface.
Step-by-step explanation:
The type of tissue that covers the epiphysis of bones and reduces friction in the joints is cartilage, specifically, articular cartilage. Articular cartilage is a smooth, thin layer of dense connective tissue that serves both to reduce friction at synovial joints during movement and to act as a shock absorber. Unlike other cartilage in the body, articular cartilage covers the entire articulating surface of each bone at a joint and is not continuous, allowing for smooth articulation of the bones.