Textbook Notes (368,369)
Canada (161,838)
Psychology (1,066)
PSY3122 (64)
Chapter 5

Chapter 5 - Male Sexual Anatomy and Physiology

4 Pages
Unlock Document

Peggy Kleinplatz

Chapter 5 – Male Sexual Anatomy and Physiology SEXUAL ANATOMY The penis: a male sexual organ consisting if the internal root and the external shaft and glans - Consists of nerves, blood vessels, fibrous tissue and 3 parallel cylinders of spongy tissue - Extensive network of muscles present at the base of the penis – these muscles eject semen and urine through the urethra - Root: the portion of the penis that extends internally into the pelvic cavity - Shaft: the length of the penis between the glans and the body - Glans: the head of the penis; it is richly endowed with nerve endings - Three cylinders: o 2 larger ones: cavernous bodies: the structures in the shaft of the penis that engorge with blood during sexual arousal o Third layer: spongy body: a cylinder that forms a bulb at the base of the penis, extends up into the penile shaft, and forms the penile glans o At the root of the penis the innermost tips of the cavernous bodies, or crura, are connected to the pubic bones - Skin covering the penile shaft is usually hairless and quite loose – allows for expansion when the penis becomes erect - Foreskin: a covering of skin over the penile glans – or prepuce o Circumcision: involves the surgical removal of the sleeve of skin covering the whole penis o Superincision: foreskin is split lengthwise along its top portion, instead of being removed o Castration: removal of the testes - Entire penis sensitive to touch – but greatest concentration of nerve endings is found in the glans o 2 specific locations are particularly responsive to stimulation  Corona: the rim, or crown – which marks the area where the glans rises abruptly from the shaft  Frenulum: a highly sensitive thin strip of skin that connects the glans to the shaft on the underside of the penis The Scrotum: the pouch of skin of the external male genitals that encloses the testes - Scrotal sac: consists of 2 layers: o Outermost layer: a covering of thing skin that is darker in colour that other body skin – becomes sparsely covered with hair at adolescence o Second layer: tunica dartos: composed of smooth muscle fibers and fibrous connective tissue - Within the scrotal sac – 2 separate compartments o Each houses a testicle – male gonad inside the scrotum that produces sperm and sex hormones o Each testis is suspended in its compartment by the spermatic cord: a cord attached to the testicle that contains the vas deferences, blood vessels, nerves and cremasteric muscle fibers - Cremasteric reflex: contractions of the cremasteric muscle (major scrotal muscle) The Testes - 2 major functions o The secretion of sex hormones o The production of sperm - Form inside the abdominal cavity and migrate through the inguinal canal from the abdomen to the scrotum in late fetal development - Cryptorchidism: a condition in which the testes fail to descent from the abdominal cavity to the scrotal sac The Seminiferous Tubules - Within the testes are 2 separate areas involved in the production and storage of sperm o Seminiferous tubules: thin, coiled structures in the testes in which sperm are produced – make up the interior of the testis o Interstitial cells (Leydig’s cell): cells located between the seminiferous tubules that are the major source of androgen in males – proximity to blood vessels allows direct secretion of their hormone products into the bloodstream The Epididymis: the structure along the back of each testis in which sperm maturation occurs – sperms produced in the seminiferous tubules move into this structure The Vas Deferens - Sperm held in the epididymis drain into the vas deferens o Vas deferens: a sperm carrying tube that begins at the testis and ends at the urethra - Vasectomy: male sterilization procedure that involves removing a section from each vas deferens - Spermatic cord exits the scrotal sac through the inguinal canal, an opening that leads directly into the abdominal cavity - Vas deferens continues its upward journey along the top of the bladder and loops around the ureter - Turning downward, the vas deferens reaches the base of the bladder, which is joined by the excretory duct of the seminal vesicle, forming the ejaculatory duct o Ejaculatory ducts: two short ducts located within the prostate gland – open into the prostatic portion of the urethra  Urethra: the tube through which urine passes from the bladder to the outside of the body The Seminal Vesicles: small glands adjacent to the terminals of the vas deferens that secrete an alkaline fluid (conductive to sperm motility) that constitutes the greatest portion of th
More Less

Related notes for PSY3122

Log In


Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.