Final answer:
The epiphysis of long bones is covered with articular cartilage which functions to reduce joint friction and absorb shock. During growth, the epiphyseal plate is also made of cartilage until it is replaced by bone when growth ceases in adulthood.
Step-by-step explanation:
The area of the long bone that is covered with cartilage is the epiphysis, which is the rounded end of a long bone. In these regions, the bone is not covered by the periosteum but is instead capped with articular cartilage. This cartilage serves to reduce friction in the joints and acts as a shock absorber. As a person grows, the epiphyseal plate (growth plate), made up of hyaline cartilage, is also present until early adulthood (approximately 18-21 years), at which point it is replaced by osseous tissue, signifying the end of growth in that bone.