embryology Flashcards
what structures in the developing face must fuse to form the upper lip and jaw?
maxillary prominence and medial nasal prominences
what embryonic structures contribute to the development of the face?
frontonasal prominences and first and second pharyngeal arches
to what structures do the 3rd and 4th pouches contribute?
parathyroid glands and thymus
which cranial nerves are associated with the pharyngeal arches?
CN V, VII, IX, X
to what structures in the head and neck do neural crest cells contribute?
cartilage bars in each of the pharyngeal arches leading to development of the skeleton of the face
which structures are secondarily retroperitoneal?
pancreas, duodenum, descending colon
which structures are retroperitoneal?
pancreas, aorta, kidneys
how does the true kidney develop?
from intermediate mesoderm in the pelvis under induction by the ureteric bud
describe the development and fate of the notochord
formed during gastrulation
drives neurulation and forms the nucleus pulposus of the IV disks
during development the gut tube is suspended by mesenteries. which region of the developing gut tube are suspended by both dorsal and ventral mesenteries?
foregut only
which structures have mesenteries?
jejunum, ileum, stomach
in a patient with an inflamed Meckel’s diverticulum, where would the pain be felt initially?
-periumbilical region
- abnormal remnant of the vitelline duct connecting the primitive gut tube to the umbilical cord at the midgut during embryonic life.
- connection permits physiological herniation of the midgut loop
midgut= periumbilical region pain
in which week of development does the embryo fold?
4th
does the folding of the embryo change the position of the cariogenic field?
yes
- moves from cranial to buccopharyngeal membrane to a position ventrally within the neck
- ultimately thorax of the embryo as a consequence of folding of the embryo in the cephalocaudal plane
which embryonic tissue gives rise to the cardiovascular system?
mesoderm
- specialised region of the mesoderm = cariogenic fields
from which structure does the vas deferens develop?
mesonephric duct
- supported by androgens
from which structure does the uterus develop?
paramesonephric duct
- absence of testis derived MIH to develop into the uterus, uterine tubes and the upper vagina
a 16/o girl presents with primary amenorrhoea. physical examination reveals female external genitalia, but testosterone levels are in excess of a normal girl. Karyotyping is XY. what is the diagnosis
androgen insensitivity syndrome
from which tissue do the gonads develop?
intermediate mesoderm in the abdomen
- gonads then descend through the abdomen
on examination a 3y/o boy is found to have a urethral opening which extends posteriorly along the ventral surface of the shaft of the penis
what is the most likely cause of this structural anomaly?
failure of the urogenital folds to fuse
- penile urethra
from which structure does the bladder develop?
urogenital sinus
which part of the nervous system mediates sensation from above and below the pectinate line respectively?
visceral and somatic
- above line: derived from handgun and has splanchnic innervation
- below line: ectoderm of the proctodeum which has a somatic supply
what Is the etiology of metal HR accelerations in utero?
- response to metal movement
what is the normal metal pO2?
4kPa
what is the normal fetal HR?
100-160 bpm
which prenatal diagnostic test has the highest risk of pregnancy loss?
chorionic villus sampling
what treatment can be given to promote fetal lung development should premature delivery be unavoidable?
corticosteroids
- promote surfactant production in fetal lungs
what is the most common cause of morbidity in premature infants?
respiratory distress syndrome
