Astructure found on the femur is the

Linea aspera.

Explanation:

Femur is the thigh bone of the body that bears the most of the body's weight. The the proximal bone of the hindlimb of the organisms is femur. This is the longest bone of the body.

The linea aspera structure is present on the femur. Linea aspera consists of the medial border and the lateral border and forms the gluteal tuberosity. The linea aspera shows the diverges proximal and distally and can also diverges to the lateral and medial ridge.

Thus, the answer is linea aspera.

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jk but i am serious about the part that most people cant answer it beacuse you did not mention the section you are talking about. but it would if you added some detail and were a bit more specific.