Penis

Thanks to its complex structure consisting of 3 erectile bodies, the penis can fulfil the functions of urine transport and reproduction. The corpus spongiosum lies on the underside of the penis and surrounds the urethra. The glans corresponds to its outer end, at the tip of which the urethra opens. The foreskin surrounds the glans.
The two erectile bodies located on the upper side of the penis are responsible for the stiffness of the penis. The complex interplay of hormonal and nerve stimulation leads to the inflow of blood into the sponge-like erectile tissue and thus to an erection.