UG-embryology Flashcards
where in the 18-day old embryo do the kidneys originate from? A-paraxial mesoderm B-splanchnopleuric mesoderm C-somatopleuric mesoderm D-Intermediate mesoderm
D
what is the destiny of the pronephros?
A-it will eventually become the definitive kidney
B-it will eventually become the definitive ureter/ collecting system
C-it will eventually become the cloaca
D-non-its transitionary and non-functional
D
which structure becomes the definitive kidney? A-pronephros B-mesonephros C-metanephros D-wolffian ducts
C
why are horseshoe kidneys in the pelvis?
A-failure of reciprocal induction causes failure to ascend
B-the blood supply arises from iliac arteries instead of the aorta
C-isthmus gets trapped by the inferior mesenteric artery
D-lack of testosterone causes failure to ascend
C
the trigone of the bladder is formed by…?
A-fusion of mesonephric (Wolffian) ducts
B-fusion of paramesonephric (Mullerian) ducts
C-thickening of the urogenital sinus
D-condensation of urachus
A
what are the definitive structures of the mesonephric (Wolffian) ducts?
A-bladder, prostate and external genitalia
B-ureter, major and minor calyces
C-fallopian tubes, uterus and upper 1/3 of vagina
D-seminal vesicles, vasa defferentia and epididymis
D
what are the definitive structures of the paramesonephric (Mullerian) ducts?
A-bladder, prostate and external genitalia
B-ureter, major and minor calyces
C-fallopian tubes, uterus and upper 1/3 of vagina
D-seminal vesicles, vasa defferentia and epididymis
C
which of the following is a remnant of the Mullarian (paramesonephric) ducts in the male? A-appendix testis B-Tunica vaginalis C-Tunica albuginea D-Gubernaculum
A
which of the following is a remnant of the Wolffian (mesonephric) ducts in the female? A-ovarian cyst B-garter's cyst C-cervical os D-round ligament
B
which hormone is responsible for the differentiation of the mesonephric ducts into the male internal sexual organs? A-SRY protein B-testosterone C-dihydrotestosterone D-antimullarian hormone
B
which hormone is responsible for the differentiation of the male external genitalia? A-SRY protein B-testosterone C-dihydrotestosterone D-antimullarian hormone
C
which of the following statements is correct in the developing female external genitalia?
A-genital tubercle becomes the clitoris
B-genital swelling becomes the labia minora
C-urethral folds become the labia majora
D-cloacal membrane becomes the urethral orifice
A
Which of the following statements is correct in the developing male external genitalia?
A-genital tubercle becomes scrotum
B-genital swelling becomes the penis (corpus cavernosum)
C-urethral folds become the corpus spongiosum (urethra)
D-the cloacal membrane becomes penile glans
C
where is the entire UG system derived from?
intermediate mesoderm
what does the intermediate mesoderm form either side of the developing aorta?
a urogenital ridge
what does the nephrogenic cord (part of UG ridge) develop into?
- pronephros
- mesonephros
- metanephros
when does the pronephros develop?
week 4
what happens to the pronephros as the mesonephros develops?
it degrades
which weeks does the mesonephros function between?
6-10
what is the mesonephros made up of?
- mesonephric (wolffian) duct
- mesonephric tubules
what does the metanephros form?
mature kidney
when is the metanephros formed?
week 5
what is the metanephros made up of?
- ureteric bud
- metanephric blastema
what does the ureteric bud give rise to (4)?
urine-secreting system including: ->collecting ducts ->minor and major calyces ->renal pelvis ->ureter
what does the metanephric blastema give rise to?
urine-forming system
what are the 4 stages of nephron development?
- Vesicle stage
- ‘S-shaped’ body stage
- Capillary loop stage
- Maturation stage
how are peritubular aggregates formed?
-signalling from ureteric bud induces metanephric blastema to condense forming p. aggregates
how is the metanephric vesicle formed?
peritubular aggregate cells undergo MET and form m. vesicle
outline the change in blood supply to the kidney as they ascend
from common iliac to aorta
what causes kidneys to ascend?
Growth of the embryo in length causes the kidneys to “ascend” upwards to their final position in the lumbar region
how do the ureters change as the kidneys ascend?
the ureters elongate and open into the bladder superiorly
what week does sexual differentiation start?
7
what does the presence of SRY protein trigger?
male development-influences formation of testes
which 4 structures of the male reproductive system does the Mesonephric (Wolffian) duct give rise to?
- Epididymis
- Vas deferens
- Seminal vesicle
- Ejaculatory duct
what is the penis formed from?
genital tubercle
what is the scrotum formed from?
labioscrotal swelling
what occurs when there is absence of SRY protein?
gonads differentiate into ovaries
what 3 structures of the female reproductive system does the paramesonephric (Mullerian) duct give rise to?
- uterus
- fallopian tubes
- upper 1/3 vagina
what is the clitoris formed from?
genital tubercle
what is the labia majora formed from?
labioscrotal swellings
what is the labia minora formed from?
urogenital folds
what does the gubernaculum do?
connects indifferent gonad to labioscrotal swelling
what does the gubernaculum do specifically in males?
pulls the testes down into the scrotum; as this happens, it passes through the anterior abdominal wall
where is the urogenital sinus formed from?
the cloaca
are the derivatives of the urogenital sinus endodermal or mesodermal?
endodermal in origin
