Flashcards in Lecture 68 - Male reproductive anatomy Deck (50):
What is the main difference between the male and female perineal membrane and deep perineal pouch?
There is no vaginal opening in males (midline fusion event during development) - there is only a urethral opening.
What is the difference between the male and female external urogenital sphincters?
There are no vaginal sphincters in the male - only the urethral sphincter.
What is the role of the urethral sphincter?
It maintains urinary continence
What structure, contained within the testes, produces spermatozoa?
The seminiferous tubules.
Where are the immature spermatozoa collected?
Where are the spermatozoa stored and matured?
What is the layer of thick connective tissue surrounds the seminiferous tubules?
The tunica albuginea
What does it mean for a spermatozoa to 'mature'?
Acquire the abilities to move and to fertilize an ovum.
What happens to the sperm if ejaculation does not occur?
They are reabsorbed in the epididymus and the components are recycled.
How many seminiferous tubules are there?
~400-600 in each teste
Where about in the abdominopelvic cavity do the ovaries/testes develop?
High up on the posterior abdominal wall, beneath the kidneys
By 7 months gestation the testes have descended towards what structure in the anterior abdominal wall?
The inguinal canal.
By what time in gestation have the testes externalized?
About 9 months, usually just before birth
The descent of the testes during development 'drags' what structures from the posterior abdominal wall?
Blood vessels, nerves, ducts (ie, vas deferens) and layers of the abdominal wall
What is the spermatic cord?
The cord-like structure in males formed by the vas deferens and surrounding tissue that run from the deep inguinal ring down to each testicle.
What is the vas deferens?
Muscular duct that transports spermatozoa to the ejaculatory duct
What is the wall of the vas deferens made of?
The vas deferens penetrates the anterior abdominal wall through what structure?
The inguinal canal.
Each vas deferens descends along what part of the pelvic cavity to meet the ducts of the seminal vesicle?
The lateral wall
What is the ejaculatory duct comprised of?
Duct of seminal vesicle and the vas deferens
Describe the path of descent of the vas deferens from the top of the pelvic cavity to the ejaculatory duct.
Lateral to the bladder and posterior to the prostate gland.
Is ejaculation mediate by the sympathetic or parasympathetic nervous system?
What is a vasectomy?
The ligation and/or severing of the vas deferens to prevent the transmission of sperm during ejaculation.
There are three accessory glands of the male reproductive system that contribute to the volume of the semen. What are they called?
Seminal vesicle, prostate, bulbourethral glands
Where is the seminal vesicle located relative to the bladder?
Along the posterior surface of the bladder
The ducts of the seminal vesicles join with the vas deferens to form the ejaculatory duct. Which other accessory gland does the ejaculatory duct empty in to?
What does the seminal vesicles contribute to the volume of the semen?
Fructose (for ENERGY!!!) and a coagulating agent
Where are the bulbourethral glands located?
In the deep perineal pouch
What is the role of the bulbourethral glands?
Secretes a mucous-like volume that lubricates the urethra, ie it forms the pre-ejaculate
Describe the location of the prostate relative to adjacent structures.
Inferior to the bladder, anterior to the rectum, Superior to the perineal membrane, surrounds the urethra
The prostate is comprised of approximately how many individual glands?
The ducts of all of the individual glands of the prostate open into what part of the urethra?
The prostatic urethra
The prostate provide approximately what % of the volume of the ejaculate?
What is one of the roles of the secretion of the prostate?
Activation of the sperm
Benign prostatic hypertrophy is enlargement of which part of the prostate?
The central portion
What is the primary symptom of benign prostatic hypertrophy? Why?
Reduced ability to urinate because of compression of the urethra.
What is the easiest way to detect benign prostatic hypertrophy? Why?
DRE - digital rectal examination.
Prostatic cancer affects the thickness of what portion of the prostate?
Trick question: affects the thickness of the entire prostate
Upon DRE, what is the difference between a prostate with benign hypertrophy and one with cancer?
Benign hypertrophy: prostate will feel 'bulky';
Cancer: prostate will feel 'rock hard' and can feel vessels.
What pelvic structures provide attachments for the external male genitalia?
Perineal membrane and pubic arch
The penis is made out of two separate erectile tissues. What are they?
Two corpora caversona (dorsal) and a single corpus spongiosum (ventral, medial)
The glans penis is an extension of which of the erectile tissue?
The urethra penetrates the perineal membrane and enters which of the erectile tissues of the penis?
Is erection mediated by the sympathetic nervous system or the parasympathetic nervous system? How?
The parasympathetic nervous system dilates blood vessels, which engorges the tissues of the penis.
Which two muscles, when they contract, pump blood from the root of the penis into the body during erection?
Ischiocavernosus and bulbospongiosus muscles
Describe the body of the penis.
Pendulous and surrounded by skin
The scrotum is a homologue of what structure in the female reproductive system?
The labia majora
What is the raphe?
The line down the middle of the scrotum that delineates the midline fusion of the labia major during development.
What is the anatomical name of the foreskin?