HD2 Anatomy2 Embryology Part 3 Flashcards
The heart develops from heart forming regions (HFR) near which end of the embryo? [1]
The cephalic end
The heart beats on which day of human development? [1]
22
What do the heart forming regions turn into? [1]
How do these products form the heart tube? [1]
Heart forming region turns into endocardial tubes
Endocardial tubes fold laterally toand fuse to form a single cardial tube
Failure of the endocardial tubes to form causes ? [1]
will develop two hearts; cardia bifida.
name and draw the 5 dilatations of the heart tube [5]
Truncus arteriosus
Bulbus cordis
Primitive ventricle
Primitive atrium
Sinus venosus
add phoot
Describe how the single endocardial tube / heart tube changes shape as it develops (and why) [3]
Cant expand more because its limited in height by the primitve paericardial cavity
embryonic ventricle to bend to now sit inferior to atria
This looping occurs to the right of the midline
photo
Endocardial cushions are established between the primordial atria and primordial ventricles to form the [] [1]
Endocardial cushions are established between the primordial atria and primordial ventricles to form the common atrio-ventricular canal (AV canal).
Describe how foramen ovale occurs
Atrial septation starts with a septum primum growing towards the endocardial cushions. Before it reaches the cushions a foramen develops in this septum. Then a second septum grows, septum sepundum. This is an incomplete septum. The hole in this septum is the foramen ovale.
If septum primum or secundum does not develop an atrial septal defect is present.
What would be the consequences of an ASD on a newborn?
No clinical effect
R to L shunt of blood
L to R shunt of blood
If septum primum or secundum does not develop an atrial septal defect is present.
What would be the consequences of an ASD on a newborn?
No clinical effect
R to L shunt of blood
L to R shunt of blood
After birth the left side of the heart is at higher pressure than the right side, so blood will travel from the left to the right.
What error does Tetralogy of Fallot arise from? [1]
Tetralogy of Fallot is a form of congenital heart disease. It results from a single error:
conus septum develops too anteriorly giving rise to 2 unequally proportioned vessels
What are the 4 characteristics of Tetralogy of Fallot
(1) VSD
(2) Overriding aorta
(3) Pulmonary stenosis
(4) Right ventricular hypertrophy.
Describe how the pancreas forms [3]
The pancreas develops from a larger dorsal divercticulum from the duodenum and a smaller ventral outpouching from the side of the common bile duct
The ventral pouch swings round posteriorly to fuse with the lower aspect of the dorsal diverticulum (trapping the superior mesenteric vessels between the two parts in the process)
What do the orignal duct of the larger and smaller portions become? [2]
The smaller segment takes over the main pancreatic flow leaving the original duct of the larger portion as the accessory duct. [2]
What is Gastroschisis?
Intestines herniate through the abdominal wall close to the umbilicus
Umbilical hernia
Inflammation of the stomach
The stomach herniating through the diaphragm
What is Gastroschisis?
Intestines herniate through the abdominal wall close to the umbilicus
Umbilical hernia
Inflammation of the stomach
The stomach herniating through the diaphragm
Gastroschisis refers to extra-abdominal herniation (evisceration) of fetal or neonatal bowel loops (and occasionally portions of the stomach and or liver) into the amniotic cavity through a para-umbilical anterior abdominal wall defect.
How does Omphalocele differ from Gastroschisis?
They dont
The herniated bowel is covered by the peritoneum
Bowel is accompanied by the pancreas
How does Omphalocele differ from Gastroschisis?
They dont
The herniated bowel is covered by the peritoneum
Bowel is accompanied by the pancreas
