Penis

Question 1

what are the two main functions of the penis

Answer 1

Sexual intercourse – During erotic stimulation, the penis undergoes erection, becoming engorged with blood. Following emission, (mixing of the components of semen in the prostatic urethra) ejaculation can occur, whereby semen moves out of the urethra through the external urethral orifice. Finally, the penis undergoes remission, returning to a flaccid state.
Micturition – The penis also has an important urinary role. It contains the urethra, which carries urine from the bladder to the external urethral orifice, where it is expelled from the body.

Question 2

what is the anatomical position of the penuis postion tof the

Answer 2

erect

Question 3

structure ofthe penus

Answer 3

Root – The most proximal, fixed part of the penis. It is located in the superficial perineal pouch of the pelvic floor, and is not visible externally. The root contains three erectile tissues (two crura and bulb of the penis), and two muscles (ischiocavernosus and bulbospongiosus).
Body – The free part of the penis, located between the root and glans. It is suspended from the pubic symphysis. It is composed of three cylinders of erectile tissue – two corpus cavernosa, and the corpus spongiosum.
Glans – The most distal part of the of penis. It is conical in shape, and is formed by the distal expansion of the corpus spongiosum. This contains the opening of the urethra, termed the external urethral orifice.

Question 4

desribe the errectile tissues of the penis

Answer 4

.
The erectile tissues fill with blood during sexual arousal, producing an erection. The root and body of the penis are spanned by three masses of erectile tissue.

In the root, these tissues are known as the left and right crura, and the bulb of the penis. The bulb is situated in the midline of the penile root, and is traversed by the urethra. The left and right crura are located laterally, attached to the ipsilateral ischial ramus.

The erectile tissues continue into the body of the penis. The left and right crura move anteriorly into the dorsal part of the penis – they form the two corpora cavernosa. They are separated by the septum of the penis, although often incompletely. The bulb forms the corpus spongiosum, which lies ventrally. The male urethra runs through the corpus spongiosum – to prevent it becoming occluded during erection the corpus spongiosum fills to a reduced pressure.

Distally, the corpus spongiosum expands to forms the glans penis.

Question 5

desribe the musclews of the penis

Answer 5

There are four muscles located in the root of the penis:

Bulbospongiosus (x2) – associated with the bulb of the penis. It contracts to empty the spongy urethra of any residual semen and urine. The anterior fibres also aid in maintaining erection by increasing the pressure in the bulb of the penis.
Ischiocavernosus (x2) – surrounds the left and right crura of the penis. It contracts to force blood from the cavernous spaces in the crura into the corpus cavernosa – this helps maintain erection.

Question 6

desribe the fascial coveering of the penis

Answer 6

Each mass of erectile tissue has two fascial coverings. The most superficial layer is the deep fascia of the penis. This is a continuation of the deep perineal fascia, and forms a strong membranous covering which binds the erectile tissues together. Underneath the deep fascia is the tunica albuginea, forming an individual capsule around each cavernous body.

Question 7

desribe the ligaments of the penis

Answer 7

ligaments
The root of the penis is supported by two ligaments, which attach it to the surrounding structures:

Suspensory ligament – a condensation of deep fascia. It connects the erectile bodies of the penis to the pubic symphysis.
Fundiform ligament – a condensation of abdominal subcutaneous tissue. It runs down from the linea alba, surrounding the penis like a sling, and attaching to the pubic symphysis.
Skin

Question 8

desribe the skin of the penis

Answer 8

The skin of the penis is more heavily pigmented than that of the rest of the body. It is connected to the underlying tunica albuginea by loose connective tissue.

The prepuce (foreskin) is a double layer of skin and fascia, located at the neck of the glans. It covers the glans to a variable extent. The prepuce is connected to the skin of the glans by the frenulum, a median fold of skin on the ventral surface of the penis. The potential space between the glans and prepuce is termed the preputial sac.