Lecture Notes: Human Penis Anatomy and Physiology

Overview

• The penis is an external sex organ and part of the male reproductive system.
• Functions include urination and ejaculation.
• Main parts: root, body, and epithelium.

Anatomy of the Penis

• Root: attached part, consisting of bulb and crura, located within the superficial perineal pouch.
• Shaft: pendulous part, supported by the suspensory ligament.
• Epithelium: includes shaft skin and foreskin covering the glans.
• Erectile Tissue: Comprised of three columns – two corpora cavernosa and one corpus spongiosum.
• Glans Penis: Tip of the penis, covered by foreskin (in uncircumcised males).
• Corona: Rounded base of the glans.

Physiology

• Erection: Involves blood engorgement, is controlled by autonomic nervous system.
• Average Size: Erect average size is 13.12 cm in length and 11.66 cm in circumference.
• Semen Displacement: Adaptation to replace rival sperm, facilitated by the coronal ridge shape.

Development

• Penis and clitoris develop from similar embryonic structures.
• Growth in puberty involves enlargement and pubic hair development.

Urination

• Urine is expelled through the urethra, passing through the prostate.
• Urination involves coordination of nervous systems.

Sexual Stimulation

• Involves the glans and frenulum as primary erogenous zones.
• Erection angle varies.

Disorders

• Paraphimosis: Inability to cover the glans with the foreskin.
• Peyronie's Disease: Curvature due to scar tissue.
• Erectile Dysfunction: Inability to maintain an erection.
• Priapism: Prolonged painful erection.
• Congenital disorders include hypospadias and micropenis.

Cultural and Social Aspects

• Circumcision: Common for cultural, religious reasons, involves removal of foreskin.
• Body Modifications: Includes piercings like Prince Albert, and tattoos.
• Terminology: Numerous slang terms exist due to cultural taboos.

Evolutionary Considerations

• Size and shape adaptations due to sperm competition.

Research and Innovations

• Efforts in genital regeneration and bioengineering for medical applications.