<prompt> Posterior gliding of tibia on femur is prevented by -Anterior cruciate ligamentPosterior cruciate ligamentMedial collateral ligamentLateral collateral ligament  <response>: Ans. is b i.e., Posterior cruciate ligament Posterior cruciate ligamento PCL begins from posterior part of intercondylar area of tibia and runs upwards, forwards and medially to attach the anterior part of the lateral surface of medial condyle of femur.o PCL is extrasynovial but intracapsular, i.e., lies betw een synovium and capsule of the knee joint,o It provides antero-posterior stability and prevents posterior gliding of tibia on femur,o It is taut in flexion.o Blood supply of cruciate anterior posterior ligaments is from : -Middle genicular artery major supplyInferior genicular medial lateral artery less important.o Nerve supply of cruciate ligaments ACL PCL is from posterior articular branch of tibial nerve. 