07a: Embryology and Placenta Histo Flashcards
The genital ridge forms in the (X) region. Germ cells migrate (to/from) there, (to/from) (Y).
X = mesonephric
To; from
Y = yolk sac (in umbilicus region)
Primitive gonad: the germ cells originate from which tissue layer?
None! Migrate from extra-embryonic yolk sac
Embryology: migration of (X) cells to (Y) part of brain follows molecular cues associated with the olfactory tract.
X = GnRH neurons Y = hypothalamus
Embryology: (X) cells surround the M and F primordial sex cells. But, in (F/M), (Y) tubules fuse with medullary ends of the sex cords. What structure will this become?
X = coelomic epithelial
M;
Y = mesonephric duct
Rete testis (and entire duct system)
Embryology: the (X) cells that surround the F primordial sex cells is basis for which future structure?
X = coelomic epithelial
Follicular cells (of primordial follicle)
Degenerating mesonephric duct becomes (X) in (M/F). Where are these structures located?
X = epooporon, paroophoron, and Gartner’s duct
F;
In wall of broad ligament (near ovary)
Embryology: the (X) cells that surround the M primordial sex cells is basis for which future structure?
X = coelomic epithelial
Sertoli cells
Embryology: (F/M) is default and (F/M) development occurs under influence of (X) protein, coded on (Y).
F; M
X = testis-determining factor (TDF)
Y = SRY (sex-determining region of Y chromosome)
At about (X) weeks GA, testes descend into (Y) through (Z).
X = 26 Y = scrotum Z = inguinal canal
As testes descend, list the structure(s) that come with them.
- Vessels and nerves
2. Some peritoneum (tunica vaginalis)
Undescended testes, a condition called (X), occurs in (Y)% of premature infants. What are some effects of this?
X = cryptorchidism; Y = 30
Sterility and increased risk for testicular cancer
Torsion of the testes involves twisting of (X).
X = spermatic cord
Degenerating paramesonephric duct becomes (X) in (M/F).
X = appendix testis and prostatic utricle
M
The “female prostate” is formally called (X) gland.
X = paraurethral
(X) uterus has double vagina.
X = didelphic
Embryology: Once (X) septum forms, the now separate (Y) migrates, in (M/F), from the rectum.
X = urorectal Y = urogenital sinus
M (in F, they stay close in proximity)
If you had to attribute development of male genitalia to one culprit, it would be (X). That’s why (excess/deficiency) of (Y) will cause M to have F-looking external genitalia at birth.
X = DHT!!
Deficiency
Y = 5-alpha-reductase (2)
The (X) is the tissue that gives rise to fetal portion of placenta. What tissue/cell types does it consist of?
X = chorion
- Extra-embryonic mesoderm
- Cytotrophoblasts
- Syncytiotrophoblasts
Epithelium of the amnion is (simple/stratified/pseudostratified) and (X)-shaped.
Simple;
X = cuboidal
The amnion is composed of which two tissue layers?
- Amniotic epithelium
2. Fetal mesoderm
Decidual cells arise from transformation of (X) cells.
X = endometrial stromal
(X) villi are large, arise from chorionic plate, and bear (Y) vessels.
X = stem Y = placental aa and vv
(X) villi fuse to (Y) of the basal plate.
X = anchoring Y = cytotrophoblasts
At term, (syncytiotrophoblasts/cytotrophoblats) line the chorionic villi and face the maternal blood space.
Syncytiotrophoblasts (ONLY)
When sperm binds its receptors in (X), (Y) phenomenon occurs to render remaining sperm unable to bind and fertilize oocyte. How quickly does this occur?
X = zona pellucida Y = Ca-mediated wave of activity
1-2 ms of sperm binding