Question

1. you also have a biceps femoris, shown on the image. what bone is this muscle named for?

the femur (thigh bone)

1. what bone is the origin of this muscle

femur
what bone is the insertion of this muscle?
is this muscle a flexor or extensor?

Explanation:

1. For the insertion of biceps femoris: The long head of the biceps femoris inserts on the head of the fibula, and the short head also inserts on the fibula (along with the lateral condyle of the tibia, but the primary associated bone is the fibula).
2. For muscle action: The biceps femoris is part of the hamstring group, which flexes the knee joint and extends the hip joint; its key functional classification related to knee movement is a flexor.

Answer:

What bone is the insertion of this muscle?
fibula (and lateral tibial condyle, primarily fibula)
Is this muscle a flexor or extensor?
flexor (it flexes the knee, and extends the hip)