Review 4.10 Flashcards
septum transversum is pushed downwards until when
it gets close to liver
when is life able to being AKA when are lungs mature enough that baby will survive outside womb
week 22
as lung comes down it cleaves off what
pleural pericardial membrane - 2 little pieces
what is inside pleural pericardial membrane
phrenic nerve
comon cardinal vein
common cardinal vein on right helps form what
SVC
common cardinal vein on left does what
goes away
cardiovasular system consists of three groups of
blood islands
what are the three groups of blood islands
bilateral -left and right heart tubes
dorsal aorta
extraembryonic blood islands
the blood islands are forced together to form single tube by what process
the lateral folding
primitive heart tube - see progenital heart cells
pg 30
progenital heart cells come from what layer
epiblast
progenital heart cells form what
left and right endothelial heart tube
myocardium is derived from what
VLPM
Every part of heart comes from VLPM except what
membranous part of interventrulcar septum
conotruncal septum
conotruncal septum forms what in mature heart
part of the ascending aorta and pulmonary trunk
epicardium heps to form what
visceral pericardium
conornary arteries
cardiac jelly helps to form what
cardiac mesencym & CT skeleton of heart - all the walls!
single undifferentiated heart tube undergoes what
cardiac looping
what is this pg 31
left horn of sinus vinosus
are there any walls in the undifferentiated tube
no
bulbus cordis is what
right side
what is outflow track
conus cordis
what is important about truncus arteriosus
where conotruncal septum arches out and is separated into pulmonary trunk & aorta
what are these two parts the two little horns pg 31
beginnig of aortic arches
septum primum goes down until it meets what
septum intermedium
what is formed first septum primium or septum intermedium
septum intermedium
why do we need the foramen primium
the right left shunt must be kept open
what happens if right left shunt is closed early
hypoplastic left heart syndrome
before septum primium fuses what happens
foramen secundum
eventually foramen primium - what will happen
fused
when will valve of oval foramen officially close off
after birth
what does foramen secundum form
valve of oval foramen
what is fusion point of oval foramen called
limbus
right venous valve starts to do what
expands and cover the primitive or the rough part
initially the entire atria are what
rough (primtiive)
left venous valve does what
expands and goes to help support septum secundum
smooth part of atria is called what
sinus venarum
how do pulmonary veins help form left atria?
pulled inside and used as “wallpaper” to help form
what are two parts of ventricular wall
muscular and membranous
which is thicker in ventricular wall: msucular or membranous
muscular wall: 2-3 x thicker
what is take home message about membranous ventricular wall
neural crest cells
what is membranous ventricular wall formed from
neural crest cells
what do neural crest cells help form?
conotruncal septum & membranous part of ventricular wall
if there is membranous interventricular septual defect there will also be what
truncus arteriosus defect
blood islands help to form what
heart tube & dorsal aorta & cardial veins
L & R supracardinal veins form what
Rt: azygous
Lt: hemiazygous & acessorry hemiazygous
what happens to posterior cardinal veins
gives off other veins and then goes away
where is liver in developin gherat
slide 37
where do aortic arches go before they hit the dorsal aorta
things have to go through arches before they go to other places
what happens to 5th pharyneal arch
degenerates as soon as its made
what hapepns to the first aortic arch
goes away
what happens to second arotic arch
goes away
what happens to 3, 4, 6 aortic arch
they stay
what does 3rd aortic arch help form
common carotid & proximal part of internal carotid
what does 4th aoritc arch help form
part of aorta, helps to form subclavian artery
what does 6th aortic arch help form
left proximal pulmonary artery & ductus arteriosus (will form the ligamentum arteriosum)
left umbilical vein helps form what
round ligament of liver
what happens to right umbilical vvein
closes very early @ 7th week
what is ductus venousus
liver bipas
what happens to ductus venosus after birth
becomes ligmentum venosum
ductus arteriosus will form what
ligementum arteriosum
will any blood go into right ventricle
yes, very small amount, to help mature right ventricle
what happens to small amount of blood that goes to right ventricle
ductus arteriosus shunts to aorta
what is nomral blood flow for fetus
right artria to left ventricle to ductus arteriosus to aorta to rest of body
what is right left shunt in fetus heart
foramen ovale
skeletal system forms what
neurocranium, torso EXCEPT sternum
all skeletal muscles formed from what
paraxial mesoderm
integument system is all from what
ectoderm
all nails, glands, hair are formed from what
ectoderm
what divides or forms the proximal distal component
AER
what does AER stand for
apical ectoderm ridge
what does AER do
tells things not to differentitae, to grow (double check)
what helps form anterior posterios differntiation of limb
retinoic acid
all skeletal muscle of head comes from what
pharyngeal arches from paraxial mesoderm
what does the epimere do
(comes from somites) form big broad muscles of back
wha does hypomere form
keep segmented nature - like itnercostal, oblique, the muscles in the front
what is limb made of
ectoderm
PLPM
paraxial mesoderm (msucles)
NO ENDODERM
what is the last thing that goes into limb
nerve and blood vessels
what is the primary axial artery of upper limb
common interosseous
post developmental life still have common interosseous?
yes - very small but still there
what does common interossueous artery form
anterior & posterior interossues which helps supply deeper muscles in anterioa and posterior upper limb
median artery - what happens post developmentally
it is not there, gets retracted
what happens to ulnar and radial artery in post natal life
they stay
ischiadic artery perfuses and then what happens
only little pieces of it are used
what comes after ishchidaic artery
femoral
what what femoral artery form
popliteal
what does popliteal artery form
posterior tibilal artery
is there discreet blood supply to posterior thigh
no
what helps supply posterior thigh postnatal
cruciate anastamoses: medial & lateral circumflex femoral, inferior gluteal
cardiac and smooth muscle develp from what
VLPM
when does urinary system develop before
slightly before genital system
how many pairs of kidneys
3
what percentage of pronephros sticks around
1%
what does pronerphros help form
nephric duct
what does nephric duct help form
mesonephric duct
what does mesonephric duct plug into
cloaclia
where does paramesonephric duct form from
intermediate mesoderm
what percent of mesonephric duct goes away
99%
what is mesonephric duct used for
epididiymus, efferent ductules, ductus deferens
why else is mesonephric duct important
mature kidney comes from mesonephric duct
if there is no mesonephric duct can kidney develop
no
uteric bud migrates from mesonephric duct to:
urogenital sinus
is urinary bladder part of hindgut
yes
two of most important pieces of urogenital sinus are what
urinary bladder
spongy urethra
suprarental part inner part is formed from what
neural crest cells inside (outer is intermediate mesoderm)
everything but inner part of suprarenal is formed from what
intermediate mesoderm
Know slide 52*
!!
what happens to paramesoneprhi duct in males
goes away
everything from blue is from what pg 56
paramesonephric duct - intermediate mesoderm
everything in yellow is what pg 56
urogenital snius -endoderm
urethral folds fuse together and penile urethra is what
endoderm
what is exception in penis
tip is ectoderm
what is the most important prominence in face - if it doesn’t fuse nothing forms correctly
mandibular prominence
what does medial nasal prominence help form
bridge of nose
tip of nose
filtrum
primary palate
primary palate fses with what
secondary palate
what must all fuse at same time
nasal septum at same time primary and secondary palate fuse
nose is ingrowht of what
ectoderm
what pharyngeal arch is involved and obliterated in tongue
first pharyngeal arch helps form ant 2/3 of tongue
second is obliterated
what mature structure does the second pharyngeal arch form if any
NOTHING - totally obliterated by the thrid
where does notochord come from
mesoderm
neural ectoderm helps from what
neural plate
neural plate is pinched off and forms what
neural tube & neural crest cells
trilaminar disk chart
in trilmaniar disk lecture
what part of the brain or spinal cord are the cells which do not come from ventricular laeyr
none of them
ventricular layer helps form what
all three layers of brain
it’s germative layer of brain and spinal cord
what 3 layer organiztaion occurs throughout brain and spinal cord
- ventricular/ependymal zone
- intermediate/mantle zone
- marginal zone
what two areas are there an addition (the three layers + something) in forebrain
neocortex, molecular
what 3 layers are added in cerebellum (hindbrain)
granular, purkinje, molecular layers
where are there increased number of motor cells in spinal cord?
cervical and lumbar enlargements
need more for muscles in upper & lower limbs
PNS is all part of what
neural crest cell
autonomic nervous system cells derive from what
neural crest cells
meninges are derived from what
neural crest cells
lens and anterior epithelim comes from what
surface ectoderm
where does diencephalon come from?
brain itself
ear is formed from waht
pharyngeal groove 1
middle ear is what
endoderm
outer ear is what
ectoderm
inner ear is what
surface ectoderm
assosciation vs syndrome
syndrome: know why it occus
association: don’t know why it occurs
meiotic nondisjunction
74
what is only monosomy compatible of life
turner syndrome
what is another name for structural
mutant gene
what is chromosomal aberrations
some lost during crossin gover (of chromosom)
dosage of teratogen in first two weeks will cause
death of blastocyst
what is most sensitive to exposure of teratogens
durong organogensis
what can be affected at any time to teratogens
fetal brain/CNS
what are especially prone to minor congenital anomaleis
ears
as number of minor congenital anomalies increase what happens
increase in major congenital anomalies
what is malformation
total absense or change - like vascular
what is disruption
partial change
What are two major structures that push septum transversum down?
lung & heart
cranial part of tracheobronchial diverticulum is surrounded by what
pharyngeal arches
What does VLPM form as lungs expand
visceral pulmonary pleura
as the lung buds expand into body coelom, what are they surrounded by
VLPM
What are the four stages of lung development?
- pseudoglandular period
- Canalicular period
- terminal sac period
- alveolar period
What week is the pseudoglandular period of the lung development
5-16 weeks
What week is the canalicular period of lung development
16-26 weeks
What week is the terminal sac period of lung developemnt
26 weeks - birth
What time period is the alveolar period of lung development
birth - 8 years
What is significant about the pseudoglandular period?
the terminal branches do not have respiratory bronchiole or alveoli = no respiration
What is significant about the canalicular period?
The terminal branches form respiratory bronchioles which form terminal sacs & have a few alveoar ducts
capillaries start to associate
by week 24 respiratory bronchioles have developed, but chance of survival poor
What is significant about terminal sac period?
more development and maturation, 2 weeks before birth surfactant at adequate levels
What is significant about the alveolar period?
90-95% alveoli will develop after birth
more surfactant & vasculature
What 3 veins does sinus venosus get?
vitelline vein
umbillical vein
common cardinal vein
What happens to most of left horn of sinus venosus?
goes away
What is the congenital defect where the apex of the heart is located on the right side of the body due to improper rotation of the heart tube?
Dextrocardia
What causes dextrocardia?
improper rotation of heart tube
Describe dextrocardia of embryonic arrest
heart is shifted slightly more than normal
Describe dextrocardia sinus inversus
heart is mirror image of normal heart but on right side
Describe Dextrocardia sinus inversus totalis
everything is reversed - it usually has congenital heart defects with it because it doesn’t reverse perfectly
What is the most common type of ASD?
Ostium Secundum atrial septal defect
What can cause ostium secundum atrial septal defect?
excessive reabosrption of septum primum or incomplete development of septum secundum
What is result of ostium secundum atrial septal defect?
left → right shunt mixing of oxygenated & deoxygenated blood
What can cause ostium primum ASD?
non-fusion of septum primum w/ septum intermedium
so you will have an actual hole in atrial wall
What is the result of ostium primum ASD?
left →right shunt mixing of oxygenated & deoxygenated blood
What can cause patent foramen ovale?
foramen ovale doesn’t seal at limbus
What is result of patent foramen ovale?
Left→Right shunt mixing of oxygenated and deoxygenated blood
What can cause hypoplastic left heart syndrome?
premature closure of foramen ovale
What is result of hypoplastic left heart syndrome?
Prevents blood from reaching left heart so its underdeveloped and right heart is enlarged-Incompatible with post natal life
What is the most common congenital heart defect?
Membranous ventricular septal defect
What causes membranous ventricular septal defect?
underdevelopment of muscular septum
misalignment of bulboconal and ventricular septa
underdevelopment of endocardial cushions
What is the result of membranous ventricular septal defect?
the muscular & membranous septal portions fail to fuse, the membranous septum is small so the VSD usually extend into surrounding muscular part
What causes persistent truncus arteriosis?
conotruncal ridges fail to form
What is the result of persistent truncus arteriosis?
both ventricles mix oxygenated & deoxygenated blood, decreasing blood oxygen concentration
What causes Abnormal location of conotruncal septa?
Transposition of great vessels-conotruncal septum grows straight down instead of a 180o twist
What is the result of Abnormal location of conotruncal septa?
This causing a transposition of the aorta to the right ventricle and pulmonary trunk to the left ventricle casing aorta to send deoxygenated blood to body
-Usually associated with atrial or ventricular septal defect or patent ductus arteriosis (Left pulmonary artery to aorta
what is the result of doublet outlet right ventricle?
abnormal truncal separation causes both aorta and pulmonary trunk to arise from right ventricle causing deoxygenated blood to be sent to body
what causes double outlet right ventricle?
abnormal truncal separation
What is doublet outlet right ventricle associated with?
ventricular septal defect, pulmonary valve stenosis, transposition of great vessels
What is the most common occuring abnormality?
tetralogy of fallot
what is tetralogy of fallot caused by?
chromosome 22 deletions & digeorge syndrome
What are the four things tetralogy of fallot is characterized by?
1. Pulmonary stenosis- narrow right ventricular region 2. Interventricular septal defect 3. Overriding of the Aorta 4. Right ventricular hypertrophy
“PROV” - prove it
List 5 postnatal vascular changes
- Umbilical arteries becomes obliterated part of the umbilical artery (branch of internal iliac)
- Left umbilical vein becomes round ligament of liver
- Right umbilical vein closes very early (7th week)
- Ductus venosus shunt ligmentum venosum
- Ductus arteriosus shunt ligmentum arteriosum
- Foramen ovale shunt fossa ovale
Describe horseshoe kidney
During ascent past right and left common iliac arteries, lower kidney poles fuse and does not ascend higher than the inferior mesenteric artery
Describe pancake kidney
A disk-shaped organ produced by congenital fusion of superior and inferior poles of the embryonic kidneys to form one mass on the midline and does not ascend higher than the inferior mesenteric artery
Describe renal agenesis
One or both kidneys may be absent
-If ureteric buds don’t grow, collecting ducts and nephrons don’t develop due to lack of induction factors between them resulting in kidneys not forming or very small leading to renal failure and anuria (no urine formation and excretion)
-Unilateral renal agenesis can be asymptomatic or produce oligohydraminos but bilateral is always fatal
Oligohydramnios and pulmonary hypoplasia (incomplete formation of the lung) because little or no urine is excreted into the amniotic cavity
Associated with other severe defects (absence of vagina and uterus, ductus deferens etc)
Describe Hydronephrosis
Dilatation of renal pelvis (*) and calices (major and minor) due to obstruction in the urinary passages resulting in major kidney damage depending if its acute or chronic
Describe double ureter
- Duplicated unilaterally or bilaterally
- May or may not be associated with the duplication of kidney next to median umbilical ligament
Describe ectopic ureter
-Ureter may open into vagina, urethra, or vestibule and usually due to faulty development of Mesonephric (Wolffian) duct
Describe duplex ureter
Splitting of ureteric bud duplicating collecting portion of kidney
Describe Ectopia vesicae/exstrophy of bladder
- Lumen of the urinary bladder may be exposed on the surface of the body and amniotic cavity due to the ventral body wall failing to close
- Due to the lack of parietal lateral plate mesoderm migration below umbilicus to form dermis (connective tissue support) for the ectodermal epithelial covering of the lumen of the bladder followed by the rupture of the thin layer of ectoderm
- Occurs mainly in males and may be associated with epispadias (urethra opens on dorsum of penis)
Describe congenital adrenal hyperplasia
Congenital adrenal hyperplasia (CAH):
-Excessive androgen production
- Females- masculization of external genitalia
- Males- maybe undetected until early childhood
- Rapid growth and accelerated skeletal muscle development
Review chart pg 60
:)
Describe cleft lip
Medial nasal prominences (nose) do not fuse maxillary (lips) nasal prominences
Describe cleft palate
-Cleft palate- 2o palate does not fuse with each other or with 1o palate
Describe cleft lip & palate
Cleft lip and palate- More severe deformity where non-fusion extends to maxilla (between 1o and 2o palate) and can be unilateral or bilateral