GENERAL HISTOLOGY

Detailed explanation-1: -The knee flexors include the set of hamstrings, gracilis, sartorius, gastrocnemius, plantaris, and popliteus . Most of these knee flexors also internally or externally rotate the knee. The hamstring muscles are the primary knee flexors.

Detailed explanation-2: -The two main muscle groups are the quadriceps on the anterior side of the knee and femur, and the hamstrings on the posterior side. The four muscles of the quadriceps: vastus lateralus, vastus medialus, vastus intermedius and rectus femoris function to extend the knee.

Detailed explanation-3: -The rectus femoris is the only quadriceps muscle that traverses both the hip and the knee joint. The rectus femoris is a powerful hip flexor, but it is largely dependent on the position of the knee and hip to assert its influence.