Genitourinary Apparatus, Pelvis, and Perineum Flashcards
What is the reasoning for the positioning of the R kidney lower than L kidney?
large right lobe of the liver (inferior rt. kidney in line with L3, superior of left kidney in line with T12)
What is the respective representation of the two types of nephrons in the kidney?
Cortical (75-80%)
Juxtamedullary (15-20%)
Other than location, what is the primary difference between the flow through each nephron?
The amount of blood that circulates through them are the same, but the pressures are different (cortical has higher pressure than juxtamedullary).
What sensations do the kidneys experience?
pain (parenchyma), pressure (parenchyma), and stretch (capsule)
Nerves to the kidneys and ureters.
autonomic plexuses - renal (least splanchnic), abdominal aortic, superior hypogastric, retrograde to spinal ganglia (T11-L2 - sensory to sympathetic)
Adrenal innervation.
celiac, abdominopelvic, Pre and Paravertebral sympathetic fibers (T10-L1) to medulla
The adrenal gland cortex arises from ________, while the medulla arises from _________.
mesoderm; ectoderm
Zones of the adrenal gland cortex from innermost to outermost.
reticularis, fasciculata, glomerulosa
The glomerulosa of the adrenal gland secretes?
ADH
This type of tissue is found in the ureters, urinary bladder, and urethra.
transitional epithelium (stratified epithelium)
Distension capabilities of the bladder are controlled by this muscle, muscularis externa of the urinary bladder, and positioned in a retroperitoneal fashion.
detrusor muscle
Urinary bladder 4 layers from innermost to outermost.
Mucosa
Submucosa
Muscularis
Serosa
Sympathetic innervation of the bladder.
With low bladder volumes, the sympathetic nervous system is stimulated (internal sphincter contracts, detrusor relaxes).
Hypogastric plexuses and nerves
Pain (superior portion, above pelvic pain line) afferents are visceral following the course of the sympathetic fibers to the upper lumbar and lower thoracic spinal ganglia.
Parasympathetic innervation of the bladder.
With low bladder volumes, the parasympathetic system is inhibited.
When the bladder is full and micturition is desired, the inhibitory signals from the brain are replaced by impulses that stimulate the parasympathetic system (and result in detrusor contraction) and that inhibit the sympathetic system (cause internal sphincter relaxation).
Pelvic splanchnics and inferior hypogastric plexus
Pain (inferior portion) afferents are visceral following the course of the parasympathetic fibers.
Innervates all the pelvic floor muscles.
pudendal nerve S2-S4
Muscles of the UG triangle.
ischiocavernosus, bulbospongiosus, deep transverse perineus, superficial transverse perineus
Levator ani
pubococcygeus, iliococcygeus, coccygeus
___________ and ___________ ligaments are the landmarks for finding the innervation to the perineal region.
Sacrospinous (seen anteriorly); sacrotuberous (seen posteriorly)
Form the sacral plexus.
S2-S4
The pudendal artery is a branch of?
internal iliac artery
Around the _____ week the sexual differentiation occurs.
6th-7th
This gene encodes for a testes determining factor (TDF), which determines the path of formation of gonads.
SRY
Development of the male external genitalia is dependent upon _____________.
dihydrotestosterone (DHT)
Area of the brain for sexual behavior.
hypothalamus
What is the significance of the sexually dimorphic nucleus?
very little or not present in females, in males it used to “plan” sexual behavior
Female counterpart to the sexually dimorphic nucleus?
ventromedial nucleus
The urogenital folds in the male fuse together on the ventral side of the developing penis, enclosing what will form the ______ ______.
spongy urethra
The urogenital folds in the female are developing into the ______ ______
labia minora
Root of the penis consists of the bulb attached to _____________ and _______________.
bulbospongiosum; ischiocavernosum
Bulbourethral (Cowper’s) Gland
- Tubuloacinar glands with simple cuboidal mucous cells and ducts joining just after prostate
- paired and associated to membranous part of urethra
- embedded in the fascia of deep transverse perineal muscle
- secretions neutralize the pH of the urethra to allow sperm to survive
Testosterone produced by ______ cells.
Leydig
All the arteries of the pelvis are branches of the ______ _____ artery, except the superior rectal artery which is a branch of the ________ _________ artery.
internal iliac; inferior mesenteric
Pelvic splanchnic nerves.
S2-S4
Lumbosacral trunk
L4-L5
Sympathetics to male genitals.
T10-L2 intermediolateral cell column neurons
Thoracic and Lumbar Splanchnics
Superior Hypogastric Plexus
- Contractions of the vas deferens, prostatic capsule, and internal urethral sphincters
- Vascular responses associated to the migration of blood from the pelvis into the helicine arteries within corpora cavernosa
Parasympathetics to male genitals.
S2-S4 intermediate gray
Pelvic Splanchnic
Inferior Hypogastric Plexus
- Vascular dilation that initiates and maintains the erection due to the contraction of the bulbospongiosus and ischiocavernosus which obstruct the venous blood flow within the cavernous sinuses of the penis.
- Engorgement of corpus cavernosum and spongiosum of the penis
Somatic (afferent, efferent, visceral)
Pudendal (S2-S4) - Skin, skeletal muscles of pelvic diaphragm and perineum
Sympathetics to the female genitals.
T10-L2 intermediolateral cell column neurons
Thoracic and Lumbar Splanchnics
Superior Hypogastric Plexus
- Contractions of the uterus; however the extent of this action is dependent of female hormonal physiological competency (estrogens, testosterone) and expression of certain neurotransmitters (DA, NE, melanocortins, OT; 5HT, PRL, endogenous opioids, etc.) .
- Vascular responses to the arteries in the vagina, vestibule and clitoris
Parasympathetics to the female genitals.
S2-S4 intermediate gray
Pelvic Splanchnic
Inferior Hypogastric Plexus
- Control muscular and mucous coats of the vagina and urethra
- Stimulation of the vestibular bulb, glands and corpora cavernosa of the clitoris
The renal pelvis, ureters, genitals, and rectum develop from what type of tissue?
intermediate mesoderm to mesonephric tissue
The hila of the kidney originally face ________, but by the 9th week of development, they have rotated to face ______________.
anterior; anteromedially
Cell type in the descending limb of loop of henle/ascending limb/proximal convoluted tubule.
simple epithelial (thin for reabsorption)
Adrenal Glands
- Flattened on one side
- Lies at superior pole of kidney in perirenal adipose tissue, may or may not be touching the kidneys
- Capsule of dense irregular connective tissue, may have septa/trabeculae
- Stroma of reticular fibers and fibroblasts
- May have a superior, middle, or inferior suprarenal artery supplying them (consistent pattern)
Epinephrine released by the adrenal glands in response to ___________ activation resulting in peripheral vasoconstriction, hypertension, increased heart rate and increased blood glucose.
sympathetic
These neuroendocrine cells in the medulla of the adrenal gland release EPI and NE into systemic circulation.
Chromaffin cells
Radiologic procedure used to view abnormalities of the urinary system.
Intravenous Pyelogram (IVP)
Most kidney stones (75%) are primarily composed of which mineral?
calcium
Are men or women more often affected by kidney stones and what are the risk factors?
men; heredity, poor diet, occupational (e.g. salesperson, bankers)
Nephrolithiasis
kidney stones
Bulk of tissue of ureter is?
muscular
The bladder migrates ________ from birth to puberty.
inferiorly
Urethra difference between males and females.
Males: 18-22 cm
Females: 4 cm
When the bladder is empty (contracted), what happens to the volume?
it goes to half its full volume
Helps to form the external urethral sphincter of the bladder.
deep transverse perineal muscle
Bartholin’s glands
posterior to vaginal canal - fluids secreted from these glands contain very weak antinflammatory agents and antimicrobial agents
Colles’ fascia
parietal peritoneum
Ischiocavernosus
muscle associated with ejaculation (and bulbospongiosus)
______ _________ is landmark separating obturator internus from the perineum.
Arcus tendineus
Urogenital triangle
contains external genitals; muscle arrangement forms urogenital diaphragm assists in urination (external urethral sphincter) and ejaculation (ischiocavernosus, bulbospongiosus)
Anal triangle
contains anus - external anal sphincter
This compartment sits inferior to border of the obturator internus fascia; extending from the ischial spine to the posterior edge of the ischiopubic ramus. It contains several branches of the pudendal nerve.
Pudendal (Alcock’s) Canal
From genital tubercle, ____ of the penis will form by week 10.
glans
Epispadias
failure of the urogenital folds to close resulting in urethra opening on the dorsum of the penis (Hypospadias is when the opening is on ventral aspect)
______ of the uterus is where the egg is implanted.
Fundus
Ligaments supporting the ovaries.
Ovarian - embedded in the mesometrium
Suspensory - holding the structure crossing the midline from the back and blending with the ovarian ligament (runs laterally) - ovarian blood vessels are embedded in this ligament
Rectouterine pouch (aka the cul-de-sac)
extension of the peritoneal cavity between the rectum and the posterior wall of the uterus in females
Rectovesical pouch
extension of the peritoneal cavity between the rectum and the posterior wall of the bladder in males
Erectile tissues of the penis.
corpora cavernosa (2) - expressed in both sides corpus spongiosum (1) - w/ spongy urethra running through it; hollow, it is not erectile tissue; does not receive blood through it, more of a sponge (flexible) corpora albuginea (tunica albugenia) - whitish line, will also be seen in the testis
Frenulum of the penis.
- lining of the foreskin in the very ventral part of the penis
- connects ventral aspect of the glans to the ventral aspect of the raphe
Dark line: Indication of the hormone levels; dark = good testosterone levels
_______ produced by seminiferous tubule.
Sperm
Testes
Reproductive functions (produce sperm) Endocrine functions (produce testosterone) Thick connective tissue capsule: tunica albuginea w/ fibrous incomplete septa divide testis into lobules - continuous from penis, divides the septa Each lobule has 1-4 seminiferous tubules with surrounding loose connective tissue, vessels and interstitial cells of Leydig.