Embryology Flashcards
From which germ layer are somites derived?
Para axial mesoderm
What is ootidogenesis?
1st and 2nd meiotic divisions during oogenesis
From which germ layer do kidneys develop?
Intermediate mesoderm
What is the embryological origin of muscles of facial expression?
Second pharyngeal arch
After fertilisation, how long before the blastocyst hatches from the zone pellucida?
5-7 days
What is the embryological origin of the thyroid cartilage and cricothyroid muscle?
4th pharyngeal arch
What is the embryological origin of the trigeminal nerve (V2, V3)?
1st pharyngeal arch
At what gestational age is meconium first found in the foetal terminal ileum?
10-12/40
Which hormones control alveolar morphogenesis during pregnancy?
Progesterone, prolactin, hPL
Which hormones stimulate ductal morphogenesis?
Oestrogen, growth hormone
What is luteoplacental shift?
Takeover of placenta from corpus luteum
Occurs 6-8 weeks
Embryological origin of ribs
Mesodermal somite
Effect of warfarin on the foetus
Stippled epiphyses (ossification of long bone growth plates)
Hypoplasia of nasal bridge
Laryngomalacia
Pectus carinatum
Ventriculomegaly
Agenesis of corpus collosum
Telebrachydactyly
Growth retardation
How many days after fertilisation does blastocyst form
5
Which germ layer does GI tract develop from
Endoderm
What kind of Hb is found in a 6/52 old baby?
Hb Gower 1 (a form of embryonic Hb made by yolk sac) lasts til around 6/52 of age
At what gestation is the yolk sac largest?
10/40
To which part of the egg does the sperm bind?
Zona Pellucida
Genetic mutation associated with congenital adrenal hypoplasia
CYP21A
Gestation at which foetus begins to produce urine
8-11 weeks
When is embryonic pole first visible on TVUS
5+3/40
Usually measures 3mm
Embryological origin of intrinsic muscles of larynx
6th pharyngeal arch
Normal diameter of yolk sac on USS
6mm
When does the foetus start making foetal immunuloglobulin M
10/40
Where in the foetus is AFP produced?
Liver
But also yolk sac, GI tract
Role of DHEA
Produced by foetal adrenal gland
Stimulates placenta to make oestragen
Oestragen maintains pregnancy
At what gestation does foetal meconium first appear in terminal ilium?
10-16/40
Embryological origin of GI tract
Endoderm
Embryological origin of epidermis
Ectoderm
Embryological origin of dermis
Mesoderm
What structure(s) arise from lateral plate mesoderm
Membranes in général
Pleura
Pericardium
Peritoneum
Visceral and parietal
What structures arise from endoderm
Lining of:
GI tract
Resp tract
Urinary bladder
Parenchyma of:
Liver
Pancreas
Thyroid and parathyroid
Ureteric bud embryological origin
Mesonephric duct
