Sigmoid Flexure

Sigmoid Flexure– The s-shaped curvature of the penis when it is retracted in the body. During sexual excitation, and erection, the sigmoid flexure disappears when the penis straightens.

Vagina

In Mammals: The vagina is the copulatory portion of the female’s reproductive tract. The vestibule portion of the vagina also serves for passage of urine during urination. The vagina also serves as a canal through which young pass when born.…