UGS Embryology Final Word Scramble
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Question | Answer |
In the 3rd week of development the embryo is made up of; | A trilaminar germ disk |
What are the 3 layers of the trilaminar germ disk? | 1) Ectoderm 2) Endoderm 3) Mesoderm |
What parts will the intraembryonic mesoderm divide into? | 1) Paraxial Mesoderm --> Muscles 2) Intermediate mesoderm --> UGS 3) Lateral Mesoderm --> Ceolom --> pleural, peritoneal, and cardiac cavities |
The intermediate mesoderm will lead to the formation of a longitudinal growth on the posterior abdominal wall called: | The UG ridge |
Where is the UG ridge located? | On both side of the mesentery of the gut |
What parts does the UG ridge divide into? | 1) Gonadal ridge 2) Nephrogenic cord |
What does the gonadal ridge form? | The testes or ovaries |
What are the 3 structures which the nephrogenic cord forms? | 1) Pronephros 2) Mesonephros 3) Metanephros |
What does the pronephros form? | The pronephric tubules and ducts Completely regresses by week 5 |
Where is the mesonephros formed? | In the thoracic and upper lumbar region |
What does the mesonephros form? | The mesenephric tubules and ducts |
The mesenephric ducts persist and open into: | The cloaca |
What does the metanephros form? | The prominent kidney |
What is the metanephros made of? | The uretric bud and the metanephric blastema |
What are the locations of the derivates of the nephrogenic cord relative to one another? | Pronephros --> cranial Mesonephros --> Middle Metanephros --> Caudal |
What is the cloaca? | The caudal part of the hindgut where the rectum and bladder form |
What is the uretric bud? | An outgrowth of the mesonephric duct |
What is the metanephric blastema? | A condensation of mesoderm within the nephrogenic cord |
If the uretric bud doesn't develop or penetrate the metanephric blastema, what occurs? | Renal agenesis |
What does the mesonephric duct form in general? | The genital ducts in males and the uretric bud A couple of vestigial remnants |
The uretric bud penetrates the metanephric duct and divides into: | Branches which will become the Major calyces in the adult |
If the ureteric bud divides before entering the metanephric blastema, this will lead to the formation of: | Double ureters and calcyes Most common form: Double ureter, double calyces, with a single kidney |
What is the origin of the uretric bud and metanephric blastema? | Mesodermal |
Collecting tubules from the uretric duct stimulate the metanephric blastema to form: | Metanephric vesicles in the metanephric cap --> Nephrons |
Where is the transitional epithelium of the ureter, pelvis, major, and minor calyces derived from? | Mesoderm of the uretric bud |
Where is the simple cuboidal epithelium of the collecting tubules derived from? | Mesoderm of the uretric bud |
Where is the simple cuboidal epithelium of the DCT derived from> | Mesoderm of the metanephric vesicle |
Where is the simple squamous epithelium of the Loop of Henle derived from? | Mesoderm of the metanepric vesicle |
Where is the simple columnar epithelium of the PCT derived from? | Mesoderm of the metanephric vesicle |
Where are the podocytes and simple squamous epithelium of Bowman's capsule derived from? | Mesoderm of the metanephric vesicle |
The urinary bladder, urethra, most of the rectum, and the inferior 2/3 of the vagina are derived from? | The cloaca |
Why will the cloacal membrane rupture eventually? | It is formed of endoderm and ectoderm only |
During the 4th-7th weeks, the cloaca is divided into: | 1) Ano-rectal canal posteriorly 2) Primitive UG sinus anteriorly |
During the 4th-7th weeks, the cloacal membrane is divided into: | 1) Anal membrane related to the GIT 2) UG membrane anteriorly |
The ano-rectal canal from the cloaca forms the: | Rectum and anal canal |
The primitive UG sinus from the cloaca forms the: | Bladder and Urethra Whole urethra in the female but only partially in the male |
At the early stages of development, into what part of the cloaca, does the mesonephric duct open? | The primitive UG sinus |
At the entrance of the mesonephric ducts, a constriction appears which divides the UG sinus into: | 1) Upper vesicourethral canal 2) Lower definite UG sinus |
The vesicourethral canal from the primitive UG sinus gives rise to: | The urinary bladder and upper prostatic urethra |
The definitive UG sinus is divided into: | 1) Pelvic part 2) Phallic part |
What does the pelvic part of the definitive UG sinus in males give off? | Lower prostatic urethra and rest of male urethra |
What does the pelvic part of the definitive UG sinus in females give off? | Most of the uretha |
What does the phallic part of the definitive UG sinus in males give off? | Penile urethra |
What does the phallic part of the definitive UG sinus in females give off? | Lower 2/3 of the vagina and the vestibule of vagina |
The vesicourethral canal is continuous with the: | Allantois |
The allantois becomes: | A fibrous cord known as the urachus/Median umbilical ligament in adults |
The lower ends of the mesonephric duct become incorporated into: | The trigone at the posterior of the bladder |
The mesonephric ducts open into the: | UG sinus below the bladder |
What is the origin of the transitional epithelium of the urinary bladder? | Endoderm of the UG sinus and gut tube |
What is the consequence of a persistent allantois? | A urachal fistula and urine draining from the umbilicus |
What is the consequence of a persistent proximal or distal allantois? | A urachal sinus |
What is the consequence of persistent allantois remnants? | Urachal cyts |
Where does the female urethra develop from? | From the pelvic part of the definitive UG sinus and part of the vesicourethral canal |
The female urethra develops endodermal outgrowths in the surrounding mesoderm which will become: | Urethral and paraurethral glands |
The vestibule of the vagina will develop endodermal outgrowths in the surrounding mesoderm which will become: | Greater vestibular glands |
What is the origin of the transitional and stratified squamous epithelium of the female urethra? | Endoderm of the UG sinus |
The prostatic, membranous, and proximal penile urethra are formed from the: | Definitive UG sinus and vesicourethral canal |
What part of the urethra does the vesicourethral canal form? | The upper half of the prostate |
The prostatic urethra develops endodermal outgrowths into the surrounding mesoderm to form: | The prostate gland |
The membranous urethra develops endodermal outgrowths into the surrounding mesoderm to form: | Bulbourethral glands |
The proximal penile urethra develops endodermal outgrowth in the surrounding mesoderm to form: | Littre's glands |
The transitional and stratified squamous epithelium of the prostatic, membranous, and proximal penile urethra is derived from: | Endoderm of the UG sinus |
What is the origin of the distal penile urethra? | Surface ectoderm called the glandular plate |
The glandular plate and membranous urethra become canalized to form: | The navicular fossa |
What is the ecotdermal septa lateral to the navicular fossa going to form? | Prepuce/Foreskin |
Where is the stratified squamous epithelium of the distal urethra derived from? | Ectoderm |
Where does the kidney ascend to and from where? | To the upper lumbar region from the sacral region |
Why does the kidney ascend? | Due to disporportionate growth of the embryo caudal to the metanephros |
What change in the kidney's direction occurs during this ascent? | The kidneys rotate 90 degrees medially |
How does blood supply to the kidney change in the embryo? | The kidney will revcieve blood supply from progressively higher levels until it reaches L2 and renal arteries develop |
If the arteries formed during the ascent of the kidney persist, this will lead to: | Supernumerary arteries |
Damage to a supernumerary artery will lead to: | Necrosis of the parenchyma because they are end arteries |
Why does renal agenesis occur? | Due to failure of the uretric buds to develops |
What are the characteristics of unilateral renal agenesis? | They are common, more so in males Asymptomatic and compatible with life |
What are the characteristics of bilateral renal agenesis? | Uncommon Lead to oligohydraminos and uterine compression of the fetus The fetus will have deformed limbs and a deformed face with wrinkly skin Incompatible with life unless a donor is available |
When does a pelvic kidney occur? | When one or both kidneys fail to ascend |
What is a kidney deformity related to pelvic kidneys? | Pancake kidneys |
When does a horseshoe kidney occur? | When inferior poles of the kidneys fuse |
Why is normal ascent arrested in horseshoe kidneys? | Because the fused portion of the kidney is snagged on the inferior mesenteric artery |
What is the major effect of Polycystic kidney disease? | Loop of Henle dilates forming large cysts |
Polycystic kidney disease is associated with cysts where else? | Liver, pancreas, and lungs |
How is PKD treated? | Dialysis or transplant |
Where does AR PKD form from? | Collecting ducts |
How common is AR PKD? | 1/115,000 births |
What is the outcome of AR PKD? | Large kidney and renal failure in infancy or childhood |
What is the prevalence of AD PKD? | 1/500-1000 births |
Where does AD PKD form? | All nephrons segments |
What is the outcome of AD PKD? | No renal failure until adulthood Less progressive than AR PKD |
When is the sexual phenotype of the fetus clear? | The 12th week of development |
What structures are similar in both sexes of fetus in early development? | The immature gonads are identical, the beginning of external genitalia is similar, and both paramesonephric and mesonephric ducts are formed in both |
What is the order of differentiation of sexual structures in fetuses? | Gonads --> Internal genitalia --> External genitalia |
Where are gonads derived from? | Coelomic/Germinal epithelium, underlying mesenchyme, and primordial germ cells |
Coelomic proliferation and condensation of mesenchyme form the: | Gondal/Genital ridge between the mesonephros and dorsal mesentery |
What structure does coelomic proliferation form other than the gonadal ridge? | Finger-like projections into the underlying mesenchyme called the primary sex cords |
Where do large primordial germ cells originate from? | The yolk sac |
How do large primordial germ cells reach the gonadal ridge? | Via the dorsal mesentery |
What structure surrounds the primordial germ cells in the gonadal ridge? | Primary sex cords |
As the gonad grows a deep groove separates it from the dorsal mesentery and mesonephros so that it is? | Suspended by its own mesentery |
What are the 2 parts of indifferent gonads? | An outer cortex and an inner medulla |
What happens to the parts of the indifferent gonad in the female? | The cortex becomes an ovary and the medulla regresses |
What happens to the parts of the indifferent gonad in the male? | The medulla becomes the testes and the cortex become the tunica albuginea |
Differentiation of the indifferent gonad depends on the absence or presence of: | The Y chromosome |
The Y chromosome carries what substance which is crucial to testes differentiation? | TDF Testis Differentiating Factor |
The primary sex cords lose their connection with the surface epithelium in the developing testes due to: | Formation of the tunica albuginea |
What structures do the primary sex cords in males form? | Seminferous cords, tubuli recti, and rete testes |
Seminferous cords are made up of what cells and secrete what substance? | Sperm and Sertoli cells --> Secrete MIF (Mullerian Inhibiting Factor) |
Mesoderm between seminiferous cords give rise to what cells? | Leydig cells |
Leydig cells secrete: | Testosterone |
What is the origin of Spermatogonia, Sertoli cells, Leydig cells, and CT stroma of the testes? | Mesodermal |
When are the seminiferous cords canalized to become tubules? | Puberty |
The rete tesits will become continuous with: | 15-20 mesenephric tubules (which will become efferent ductules) |
Efferent ductules are connected to the mesonephric duct which will become: | The epididymis, vas deferens, seminal vesicles, and ejaculatory ducts |
When do Leydig cells begin testosterone production? | By the 8th week of gestation |
Where do the testes descend from and into where? | From the abdomen into the scrotum |
Why is descent of the testes 'relative'? | Because it is due to disproportionate growth of the upper abdominal region away from the pelvic region |
What is the gubernaculum? | Ligamentous remnants from the regression of the mesonephros |
Where does the gubernaculum attach? | It passes through the abdominal wall at the site of the future inguinal canal and attaches to the genital swlling |
Where does the gubernaculum extend from? | The lower pole of the tests along the posterior body wall |
Why are the testes held back when the body grows? | Because the gubernaculum does not grow in proportion |
On each side, what sac of peritoneum extend into the scrotum ventral to the gubernaculum? | The vaginal process |
Final descent of the testes through the inguinal canal into the scrotum is regulated by: | Gonadotrophic and androgenic hormones |
The gubernaculum becoming short causes the testes to: | Migrate into the scrotum posterior to the vaginal process |
What happens to the proximal vaginal process when the testes enters the scrotum? | The proximal vaginal process becomes obliterated |
What happens to the distal vaginal process when the testes enters the scrotum? | It surrounds the anterior testes and persists as the tunica vaginalis |
What is the purpose of the remnant of the gubernaculum in the scrotum? | Anchors the testes in the scrotum Prevents twisting on its spermatic cord |
What is cryptorchidism? | Failure of the testes to descend either unilaterally or bilaterally |
What is the main causes of cryptorchidism? | Abnormal androgen production or failure of the gubernaculum to become short |
What are the possible locations of the testes in cryptorchidism? | Abdomen, inguinal canal, or superficial inguinal ring |
What are the consequences of cryptorchidism? | Impaired spermatogenesis and atropy of the testes Increased risk of Malignancy Associated with congenital inguinal hernia |
What are the possible locations of ectopic testes? | Lower abdominal wall, medial thigh, base of penis, or perineum |
What is the cause of Congenital inguinal hernia? | Persistent vaginal process allowing an intestinal loop to descend into the scrotum |
What condition is a congenital inguinal hernia associated with? | Cryptorchidism |
What is the cause of hydrocele? | Accumulation of fluid in an unobliterated portion of the vaginal process |
If the abdominal portion of the vaginal process is unobliterated: | No herniation occurs, but peritoneal fluid can enter |
If the middle portion of the vaginal process is unobliterated: | Hydrocele of the spermatic cord |
In the developing ovary, the primary sex cords develop into; | The rete ovari which degenerates |
What cords develops in the developing ovary and incorporate primordial germ cells? | Secondary sex cords |
What covering develops around the gonads of both sexes? | Tunica albuginea |
Secondary sex cords break apart and form: | Isolated clusters of primordial follicles |
What is the origin of primary oocytes, follicular cells, and CT stroma of the ovaries? | Mesodermal |
What are the steps for descent of the ovaries? | 1) Gubernaculum pulls them into the pelvis 2) Gubernaculum becomes attached near the entry of the uterine tube 3) Ovary is directed medially into the pelvis |
The gubernaculum which extends from the medial pole of the ovary to the uterus forms: | The ovarian ligament |
The gubernaculum which extends from the uterus to the labia majora forms: | The round ligament of the uterus |
What is the function of MIF secreted from Sertoli cells in the embryo? | Suppression of paramesonephric ducts |
What is the function of testosterone from Leydig cells in the embryo? | Stimulation of mesonephric ducts |
What is the function of DHT in the embryo? | Stimulation of external genitalia, penis, scrotum, and prostate |
What is the function of estrogen in the embryo? | Stimulation of paramesonephric ducts and external genitalia |
Testosterone from Leydig cells are converted into DHT by: | 5 alpha reductase |
How do testosterone and DHT aid in differentiation of external and internal genitalia? | Testosterone and DHT bind to specific high-affinity IC receptor proteins This hormone-receptor complex binds to DNA to regulate transcription of tissue-specific genes and their protein products |
What are the paramesonephric ducts? | Invaginations of the lateral UG ridge |
What are the derivatives of the cranial portions of the paramesonephric ducts in females? | Uterine tubes and the hydatid of Morgagni |
What are the derivatives of the caudal portions of the paramesonephric ducts in females? | They fuse to form the UV primordium which forms the uterus, cervix, and superior third of the vagina They also bring together folds of peritoneum to form the broad ligaments |
The UV primordium projects into the dorsal wall of the UG sinus and induces what? | The formation of the sinovaginal bulbs |
The sinovaginal bulbs fuse to form the: | Vaginal plate |
When the solid vaginal plate canalizes it forms: | The inferior 2/3 of the vagina |
What is the origin of the epithelial lining of the vagina? | Endodermal |
What separates the lumen of the vagina from the UG sinus? | The hymen |
What are the derivatives of the mesonephric ducts in the female? | The metanephric kidneys |
What are the vestigial remnants of the mesonephric ducts and tubules in the females? | Appendix vesiculosa, epoophoron, paroophorn, and Gartner's duct |
As the paramesonephric ducts turn medially to fuse, they bring together peritoneal folds which give rise to: | 1) Left and right broad ligaments 2) 2 peritoneal compartments, the urorectal pouch and uterovesical pouch |
What is the cause of agenesis of the uterus? | Failure of the paramesonephric ducts to develop Failure of the vaginal plate |
What is the cause of the rudimentary uterus? | Underdevelopment of caudal paramesonephric ducts |
What are the causes of duplication and atresia of the uterine canal? | Lack of fusion of the paramesonephric ducts |
What are the types of duplication and atresia of the uterine canal? | 1) Uterus didelphys 2) Uterus Arcuatus 3) Uterus bicornis 4) Atresia with the rudimentary part lying as an appendage 5) Cervical atresia 6) Atresia of the vagina |
What is uterus didelphys? | The most extreme form of uterus duplication Completely double uteri |
What is the uterus arcuatus? | Slightly indented uterus Least extreme form of uterus duplication |
What is uterus bicornis? | Uterus has two horns entering 1 vagina Most common |
What is bicornis unicollis with 1 rudimentary horn? | Atresia with the rudimentary part lying as an appendage |
How does cervical atresia occur? | The lower part of both uteruses are atretic |
How does atresia of the vagina occur? | The sinovaginal bulbs fail to develop |
What else is seen with atresia of the vagina? | A small vaginal pouch from the paramesonephric ducts surrounds the opening of the cervix |
If the sinovaginal bulbs develop BUT do not FUSE, what happens? | Double vagina |
What is the fate of the paramesonephric ducts in males? | The cranial portions and UV primordium regress completely Appendix testes persists |
What are the derivatives of the mesonephric ducts in males? | The definitive adult kidney, epididymis, vas deferens, seminal vesicles, and ejaculatory duct Vestigial remnants of cranial ends --> appendix epididymis |
What are the derivatives of the mesonephric tubules in males? | Efferent tubules Vestigial remnants --> Paradidymis |
What is the job of the testes in differentiation of the male external genitalia? | Production of androgens which stimulate the growth and development |
The phallus elongates in the development of the male genitalia to form: | The penis |
Elongation of the phallus pulls the UG folds forward to form: | A urethral groove |
The urethral groove is continuous with: | The UG opening |
The cavity of the definitive UG sinus extends onto the surface of the: | Enlarging genital tubercle and its endodermal lined urethral groove |
The urethral groove is temporarily filled with: | A solid endodermal urethral plate which recanalizes to form an even deeper groove |
What is the difference between the urethral groove in males and females? | Males --> Groove is long and broad Females --> Groove is shorter |
When the UG folds are fused, the urethral plate in men is transformed into: | The penile urethra |
How is the tip of the glans penis formed? | Ectodermal cell cord grows inward toward the lumen of the urethra |
When the ectodermal cell ingrowth at the tip of the penis obtains a lumen, this provides a communication between: | The bladder and the end of the penis |
Skin at the base of the glans grows and becomes the: | Foreskin/Prepuce |
Labioscrotal swellings in the male migrate caudally and grow towards each other to form: | The scrotum |
What does the genital tubercle in the male form? | The glans and shaft of penis |
What does the definitve UG sinus in the male form? | The penile urethra |
What does the urethral fold in the male form? | The penis around the penile urethra |
What do the labioscrotal folds in the male form? | Scrotum |
What is the cause of hypospadias? | Incomplete fusion of the UG folds or failure of the ectodermal ingrowth from the glans Due to inadequate androgen production at a critical stage in the fusion of the urethral folds |
What is hypospadias characterized by? | Abnormal openings of the urethra on the inferior aspect of the penis An underdeveloped penis |
What will complete failure of the urethral folds to fuse lead to? | A sagittal slit along the entire length of the penis and scrotum |
What is the cause of epispadias? | Development of the genital tubercle caudally in the region of the urorectal septum The UG membrane ruptures and UG sinus opens on dorsal surface of the penis |
What is epispadias characterized by? | Urethral openings on the dorsum of the penis |
What condition is epispadias characterized by? | Exstrophy of the bladder |
What is Exstrophy of the bladder/Ectopia vesica? | When the posterior wall of the bladder is exposed to the exterior |
What is the cause of Ectopia vesicae? | Failure of the anterior abdominal wall and anterior bladder wall development |
What are the clinical manifestations of ectopica vesicae? | Associated with urine drainage to the exterior and epispadias |
How is external genitalia development in the female stimulated? | In the absence of androgens, estrogen stimulate it |
What happens to the phallus in females? | It undergoes only slight enlargement to form the clitoris |
What happens to the UG folds in the female embryo? | They do not fuse and form the labia minora |
What happens to the genital swellings/labioscrotal swellings in the female? | Labia majora Fuse anteriorly to produce and elevation--> Mons pubis Posterior margins unite --> Posterior labial commisure |
The area inside the labia minora which was not enclosed by UG folds becomes the: | Vestibule of the vagina Contains the opening of urethra and vagina |
What is the Epoophoron? | 10-15 parallel tubules in the lateral mesoalpinx between the ovary and uterine tube |
What is the Epoophoron a remnant of? | Cranial mesonephric tubules which are attached to the mesonephric ducts |
Where do the tubules of the Epoophoron end? | Inferiorly in the hilus of the ovary blindly Upper ends open into a rudimentary duct (Duct of Epoophoron) |
What is the Paraoophoron? | Few, very short rudimentary tubules in the broad ligaments |
What is the Paraophoron a remnant of? | The caudal mesonephric tubules not attached to the mesonephric ducts |
Where doe the tubules of the Paraoophorn end? | Both ends are blind |
What is the duct of Epoophoron? | A remnant of the mesonephric duct |
If the duct of Epoophorn persists, what forms? | The Duct of Gartner A cyst in the anterior of lateral vaginal wall |
What is the path of the duct of Epoophorn? | Traced along the uterine tube --> Lateral margin of the uterus --> up to the level of the internal os --> runs through the cervix and lateral vaginal wall --> ends in the free margin of the hymen |
What is the Vesicular appendix? | One of 2 pedunculated cysts attached to the fimbriated end of the uterine tube |
What is the vesicular appendix a remnant of? | The cranial end of paramesonephric ducts |
What form of hemaphroditism is seen in humans? | Pseudohemaphrotidism |
What is Pseudohemaphrotidism? | Having the gonads of one sex and the external genitalia of the other |
How are individuals born with hemaphroditism identified genetically? | By identifying the sex chromatin body/Barr body --> females |
What is Female Pseudohemaphroditism? | Ovaries and male external genitalia |
What is the main cause of Female Pseudohemaphroditism? | Congenital adrenal hyperplasia which leads to increase production of androgen Mostly due to 21 beta hydroxylase deficiency --> no corticoid synthesis--> accumulation of steroid intermediates --> adrenal androgen production |
What are the clinical manifestations of Female Pseudohemaphroditism? | Clitoris hypertrophy, partial fusion of the labia majora, and persistent UG sinus |
What is the less common cause of Female Pseudohemaphroditism? | Progestin administration during pregnancy |
What is the cause of almost 50% of ambiguous external genitalia? | Female Pseudohemaphroditism |
What is the cause of Male Pseudohemaphroditism? | Insufficient androgen or production AFTER the critical stages |
What is Gartner's cysts? | Unobliterated remnants of the mesonephric duct of Epoophorn in the wall of the vagina |
What is the Congenital rectovaginal fistula? | When the uterine canal abnormally opens into the anorectal dorsal cloaca |
What is the cause of congenital rectovaginal fistula? | Incomplete development of the urorectal septum |
What is a congenital vesicovaginal fistula? | Abnormal opening of the uterine canal into the vesiocurethral canal instead of the definitive UG sinus |
What is Turner's syndrome? | Gonadal dysgenesis No gonadal formation |
What is the genetic characteristic of Turners syndrome? | 44XO chromosomes Absent Barr body |
What is the cause of Turners syndrome? | Non-dysjunction in the male gamete during meiosis Most germ cells degenerate after migration --> No gonadal formation |
What happens to the reproductive organs in Turners? | Paramesonephric ducts and female external genitalia but no further development after birth --> infantile sex characteristics |
What is the prevalence of Turners? | 2/3000 births |
What are the clinical manifestations of Turners/ | Short Stature Webbed Neck Broad Chest with wide-spaced nipples Lymphedema of the leg from birth |
What are the genetic characteristics of pure gonadal dysgenesis? | NO chromosomal abnormalities |
What are the causes of pure gonadal dysgenesis? | Primordial germ cells do not form or migrate into gonadal area No testes or ovaries develop Absence of androgens and MIF |
What is Androgen insensitivity syndrome/Testicular feminization? | 44XY with the appearance of a normal female |
What are the causes of androgen insensitivity syndrome? | The tissues of external genitalia are unresponsive to androgens by testes |
What are the characteristics of patients with androgen insensitivity? | Testes produce MIF and paramesonephric ducts are supressed Uterine tubes and uterus do not develop Short, blind vagina Testes in the inguinal or labial region NO spermatogenesis |
What is the Barr body? | An inactivated X chromosome near the nuclear membrane Small mass of chromatin projecting fro the nucleus of Polymorphonuclear leukoocytes in females |
What does the presence of the Barr body indicate? | Indicates the presence 2X chromosomes, but not necessarily a normal genetic individual Could be XX, XXY, or XXX |
When do 2 Barr bodies appear in some nuclei? | In XXX individuals |
Absence of the Barr body indicates: | Male or incomplete female |
What are the sources of progesterone and estrogen in pregnancy? | CL produces progesterone and estrogen during the first 3-4 months Afterwards the placenta assumes this function |
What are the functions of hCG? | Saves the CL from degeneration Allows CL to form progesterone, estrogen, and relaxin |
When does hCG peak and what is its use clinically? | Peaks at 2-3 months, then decreases Is found in urine a few weeks after fertilization --> Pregnancy tests |
What are the functions of progesterone and estrogen in pregnancy? | 1) Maintain the endometrium 2) Prepare the mammary glands for lactation 3) Prepare the mothers body for birth |
What are the levels of progesterone and estrogen in pregnancy? | They increase all throughout pregnancy |
What are the functions of hCS? | 1) Prepare mammary glands for lactation 2) Enhances growth by increased protein synthesis 3) Decreased glucose use and increased fatty acid use for ATP production |
What are the functions of Relaxin? | 1) Increases flexibility 2) Dilates the uterine cervix during labor |
What are the functions of CRH? | 1) Establishes timing of birth 2) Increase cortisol secretion --> surfactant production |
What are the CRH levels during pregnancy? | Secretion begins at 12 weeks |
What is the clinical importance of CRH? | Increased levels indicate a greater possibility of premature delivery |
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Ulaisl
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