Embryology Flashcards
Urinary bladder and urethra are embryologically derived from
Primitive urogenital sinus
Persistent yolk sac lead to what condition
Meckels diverticulum
6th pharyngeal arch gives rise to
Intrinsic muscle of larynx
A Bicornuate uterus is due to
Abnormal fusion and reabsorption of the paramesonephric ducts
How many oocytes are available at the time of puberty?
400 000
The vitelline veins give rise to
the hepatic veins
the inferior part of the inferior vena cava
the superior mesenteric vein
the portal vein.
❌ The inferior mesenteric vein is not a derivative of the vitelline vein. 📕
What is the best indicator of gestational age on a dating scan in the first trimester?
Crown rump length
Omphalocoele is an abnormal herniation of
Midgut and yolk sac
Passage of sperm through epidydmis takes how many days?
8-14 days
C cells of thyroid derived from
Pouch of the 4th pharyngeal arch
The cells of which structure form the chorionic villi?
Extraembryonic mesoderm
Equivalent to vagina in males
Prostatic utricle
P.s The prostatic utricle is a small, epithelium-lined diverticulum of the prostatic urethra.
From which structure is the external auditory meatus derived?
Cleft of 1st pharyngeal pouch
Origin of urogenital sinus
Endoderm
Protective layer of graafine follicle
Theca externa
P.s. zona pellucida is the protective layer of oocyte
The renal tubules develop from
metanephrons
Derivatives of 1st Pharyngeal Pouch
-Tubotympanic recess
-Middle Ear
-Auditory tube
-Tubal Tonsil
Derivatives of 2nd Pharyngeal Pouch
Palantine Tonsil
Derivatives of 3rd Pharyngeal Pouch
Dorsal: Inferior Parathyroid Gland
Ventral: Thymus gland
Derivatives of 4th Pharyngeal Pouch
Dorsal: superior parathyroid gland
Ventral: Ultimobranchial body
Derivatives of 5th Pharyngeal Pouch
-Ultimobranchial body (fuses with lateral lobe of thyroid gland)
-Parafollicular cells
embryological origin of perineal body
Tip of Urorectal septum
At what stage of meiosis is the oocyte after ovulation?
Metaphase 2
At what age does meconium first appears in fetal terminal ileum?
10-16 weeks