Final answer:
The menisci (medial meniscus and lateral meniscus) serve as shock absorbers for the knee joint, providing cushioning between the femur and tibia.
Step-by-step explanation:
The structure serving as an absorber for the knee joint is the menisci. Specifically, there are two types, the medial meniscus and lateral meniscus. Both are C-shaped fibrocartilage structures that provide padding and shock absorption between the articulating surfaces of the femur and tibia. While they both contribute to the overall function of the knee, the medial meniscus is also attached to the tibial collateral ligament and hence shows lesser movement. The menisci's role is to fill the gap between the round femoral condyles and flattened tibial condyles, aiding stability and shock absorption during activities such as walking or running. These structures are crucial for the cushioning and smooth movement of the knee joint.