Lecture 18 Flashcards
What is the scrotum
Sack of skin that houses the testicles
What is the sack of skin that houses the testicles
The scrotum
What provides one compartment per testis
A midline septum
What is the scrotum temps comparted to the body
3 degrees lower
Why is it colder in the scrotum than the body
Spermatogenesis cannot occur at normal body temps
What are the two tunics of the testicles
Tunica vaginalis
Tunica albuginea
What is the outer layer of the testicle
Tunica vaginalis
How many layers is the tunica vaginalis
2
What is the tunica vaginalis derived from
The peritoneum
What is the fibrous capsule of the testes
Tunica albuginea
What testes tunica has septal extensions that divide each testis into 250-300 wedge shaped lobules
Tunica albuginea
How many seminiferous tubules in each lobule
1-4
What do the cremaster and dartos muscles do
Control how far the testes are from the male’s body
Contracts on a cold day to keep warm and vice versa
What muscles control how close the testes are to the body
cremaster
Dartos
What is the pathway that sperm takes to the vas deferens
Seminiferous tubules
Straight tubule
Rete testes
Efferent ductules
Epididymis
What do the leydig cells produce
Androgens
What cell produces androgens
Leydig cells
Where are the leydig cells
Betwen the seminiferous tubules
Where do the testicular arteries branch from
Abdominal aorta
What do the testicular veins form
Pampiniform plexus
What is the pampiniform plexus
The network of vein leaving the testis
What is the function of the pampiniform plexus
It’s near the testicular artery, and is branched out to allow the blood to warm quickly before going back to systemic circulation
Where does the head of the epididymis recieve sperm from
The efferent ductules
Describe the sperm that enter the epididymis
Immature, nonmotile
How long does it take to traverse the epididymis
20 days
When do sperm gain the ability to swim
In the epididymis
What happens to the epididymis during ejaculation
The tail contracts and forces the sperm out
How long can sperm last
a couple months
How long is the vas deferens
45 cm
What is another name for the vas deferens
Ductus deferens
What is another name for the tubulus rectus
Straight tubule
What is the ejaculatory duct
short part of tubing before the urethra and vas deferens meet
what is a vasectomy
cutting the vas deferens, very low risk
What are the three regions of the urethra
Prostatic urethra
Intermediate part of urethra
Spongy urethra
Where is the prostatic urethra
Travelling through the prostate gland
Where is the intermediate part of the urethra
It passes through the urogenital diaphragm
When does the urethra become the spongy urethra
As soon as it enters the penis
What percent of semen volume do the seminal vesicles contribute
70%
Where are the seminal vesicles
At the posterior wall of the bladder
Why is the seminal vesicle’s secretions yellow
Due to flavin proteins
What is contained in the seminal vesicle fluid
Nutrition for sperm, and other substances to promote motility and fertilization
What nutrition do sperm use
Fructose
Do sperm use glucose
Nope
What is the function of coagulating enzyme
Prevents sperm from spilling out, it gels up the semen
What gels up the sperm to prevent it from spilling out
Coagulating enzyme
What percent of semen volume does the prostate gland give
1/3
What gives semen the milky secretion
Prostate gland
Where are the bulbourethral glands
Inferior to the prostate glands
What do the bulbourethral glands do
Neutralizes acid residue in urethra from urine, and acidity of vagina
What gland produces an alkaline mucus to neutralize acidity
Bulbourethral glands
What are the two parts of the external genitalia
Penis
Scrotum
What composes the penis
Attached root
Free shaft (body)
What is another word for the foreskin
Cuff of skin around the glands
What is the glans penis
The tip of the penis
What is the name for the tip of the penis
The glans penis
What does the penis contain internally
Spongy urethra
3 corpora of erectile tissue
What are the 3 corpora of erectile tissue
2 corpora cavernosa
1 midventral corpus spongiosum
What corpus surrounds the urethra
Corpus spongiosum
What does the corpus spongiosum surround
Spongy Urethra
What is PSA
Prostate specific antigen
What could higher levels of PSA indicate
Cancer or enlargement of the prostate gland
What do the two corpora cavernosa surround
Deep arteries
What is the pH of semen
7.2-76
What is the pH of the vagina
3.5-4
What is a germ cell
A cell that develops into a reproductive cell
What is the source of germ cells and hormones
The testes
What do the seminiferous tubules consist of
Sertoli cells
Spermatogenesis intermediates
What percent of testicle cells are the seminiferous tubules
80
Where does spermatogenesis occur
In between sertoli cells
What are the steps to go from cholesterol to testosterone
Cholesterol
Progesterone
Androstenedione
Testosterone
What is the precursor to testosterone
Androstenedione
what are the 4 things that testosterone target
Gonadal actions
Somatic
Metabolic
CNS
Gonadotropins are what kind of proteins
Glycoproteins
What are the two main gonadotropic hormones
FSH
LH
What does FSH do
Stimulates sertoli cells to support spermatogenesis
What is necessary to begin spermatogenesis
Testosterone
What does LH do
Stimulates leydig cells to secrete testosterone
What stimulates leydig cells to secrete testosterone
LH
What stimulates sertoli cells to support spermatogenesis
FSH
What releases LH and FSH
anterior pituitary
What is GnRH
gonadotropin releasing hormone
What stimulates secretion of FSH and LH
GnRH
what secretes gonadotropin releasing hormone
Hypothalamic neurons
What releases inhibin
Sertoli cells
What do sertoli cells release that inhibits secretion of FSH
Inhibin
Why is inhibin important
It allows you to separate and regulate the secretion of LH and FSH separately, since they’re secreted together
what is the male perineum
suspends the scrotum, contains root of the penis and anus
