Reproduction Flashcards
When are fetuses most susceptible to teratogens?
3-8 weeks (embryonic period)
Branchial pouch derivatives
“Ears, Tonsils, Bottom to top”
1) Middle ear cavity, Eustachian tube, mastoid air cells
2) Tonsils
3) Lower parathyroids, thymus
4) Upper parathyroids
Neural crest cells derivations
MOTEL PASS
Melanocytes, odontoblasts, tracheal cartilage, enterochromaffin cells, laryngeal cartilage/langerhans cells, parafollicular cells of the thyroid, adrenal medulla and all ganglia, Schwann cells, and spiral membrane
Maternal diabetes can cause what problems in utero?
o Caudal regression syndrome (anal atresia to syringomyelia)
o Congenital heart defects (transposition of the great arteries)
o Neural tube defects
o Macrosomia
Causes of polyhydramnios
tracheoesophageal atresia and anencephaly
Dax1 gene
Found on X chromosome
When two X’s are present (females): facilitates ovary development and suppresses testis development
When only one X is present (males): facilitates testes formation
SRY gene
Found on Y chromosome
Inhibits ovary differentiation and induces the development of Sertoli and Leydig cells in the testes
Lymph drainage: Ovaries/testes
para-aortic LN
Lymph drainage: Prostate/cervix
internal iliac LN
Lymph drainage: Distal vagina/vulva/scrotum
superficial inguinal nodes
Lymph drainage: Glans penis
deep inguinal nodes
Where is a varicocele more common? Why?
On the left – the left testicular vein drains into the left renal vein, while the right testicular vein drains directly into the IVC
How do the testes regulate temperature?
Held away from or closer to the body via the spermatic cord
Pampiniform plexus uses countervurrent exchange of heat from the testicular artery to the venous plexus – blood cools before it reaches the testes
Sertoli Cells
form the epithelium of the seminiferous tubules within which the spermatogenic cells undergo mitosis/meiosis to form spermatozoa
Produce inhibin- negative feedback on FSH
Secrete androgen binding protein in response to FSH to maintain local levels of testosterone needed for spermatogenesis
Produce MIS
Tight junctions form blood-testis barrier → prevent autoimmune attack on sperm
Leydig cells
In the connective tissue stroma surrounding seminiferous tubules
Synthesize testosterone in response to LH
erections
tx of erectile dysfunction
parasympathetic activity (pelvic nerve)
Nitric Oxide → inc cGMP → smooth muscle relaxation → vasodilation → erection
o PDE-5 inhibitors (Sildenafil) decrease breakdown of cGMP and are used for erectile dysfunction
Where do FSH and LH act in the testes?
LH acts on Leydig cells –> promote synthesis of testosterone
FSH acts on sertoli cells –> androgen binding protein to concentrate testosterone in seminiferous tubules
Where do spermatozoa mature and develop the capacity for motility?
In the epididymis (due to the binding of glycoproteins to specific regions of the spermatozoan plasma membrane)
Myeloid cells of the seminiferous tubules
Form the outer wall of the seminiferous tubules
Modified fibroblasts that exhibits rhythmic contractions that aid in the movement of spermatozoa through seminiferous tubules
What structure does the urethra pass through in the penis?
The corpus spongiosum
Where is testosterone converted to DHT? By what enzyme?
5a reductase in the skin, prostate, seminal vesicles and liver
Two cell theory
Androgens synthesized by Theca cells (in response to LH) diffuse across the basal lamina to Granulosa cells and is converted to estrogens by aromatase (in response to FSH)
Proliferative Phase
Days 5-14
Estrogen dependent
In response to inc estrogen (from the developing ovarian follicles), stem cells in the stratum basalis undergo rapid proliferation – prep for pregnancy
Secretory phase
Days 14-28 (post-ovulation)
Progesterone dependentIn response to progesterone from the corpus luteum, the endometrial glands become coiled and secrete nutrition
In absence of pregnancy, progesterone levels decrease and the stratum functionalis begins to deteriorate
Coiled arteries in the endometrium close, resulting in ischemia and shedding of the stratum functionalis