Chapter 2: Thorax (continued 2) Flashcards
Where are the alveolar macrophages derived from?
monoctyes that exit the blood vessels in the lungs
What are some other common names of alveolar macrophages?
dust cells or heart failure cells (because they have phagocytosed blood cells that have escaped into the alveolar space during CHF
The heart begins to develop from what embryological layer?
splanchnic mesoderm
The primitive heart tube has what 5 dilations?
Truncus arteriosus
bulbus cordis
primitive ventricle
primitive atrium
sinus venosus
The primitive ventricle fuses with what embryological part of the primitive heart tube?
bulbus cordis
The primitive atrium fuses with what part of the primitive heart tube to form the atrium?
the sinus venosus
Describe the embryological origin of the rough and smooth parts of the ventricle.
smooth part ventricle: bulbus cordis
rough part ventricle: primitive ventricle
Describe the embryological origin of the rough and smooth parts of the atria.
smooth part atria: sinus venosus
rough part atria: primitive atrium
The truncus arteriosus has what embryological origin?
neural crest cells
In fetal circulation, what are the 3 major venous systems that flow into the sinus venosus end of the heart tube?
The vitelline (omphalomesenteric) veins
umbilical vein
cardinal veins
What structures does the vitelline veins drain?
drains deoxygenated blood from the yolk stalk; they will coalesce and form the veins of the liver (sinusoids, hepatic portal vein, hepatic vein) and part of the inferior vena cava
What structures do the cardinal veins drain?
carry deoxygenated blood from the body of the embryo; they will coalesce and contribute to some of the major veins of the body (brachiocephalic, superior vena cava, inferior vena cava, azygos, renal)
What is the function of the ductus venosus? Describe flow of blood to heart and to systemic circulation.
allows oxygenated blood in the umbilical vein to bypass the sinusoids of the liver into the IVC and to the right atrium. From the right atrium oxygenated blood flows mostly through the foramen ovale into the left atrium then left ventricle and into the systemic circulation
Is the ductus arteriosus proximal or distal to the the left subclavian artery?
distal to
What does the ductus arteriosus become as an adult?
liagmentum arteriosum
What does the foramen ovale become after birth?
fossa ovalis
What does the ductus venosus become after birth?
ligamentum venosum
The left and right umbilical arteries become what structure of the adult?
medial umbilical ligaments
What does the closure of the umbilical v. become in the adult?
ligamentum teres of the liver
What factors lead to the closure of the ductus arteriosus?
- the rise in bradykinin
- immediate drop of PGs
- the increase in oxygenation
When does septation of the atria and ventricles typically begin and finish?
week 4 and is mostly finished by week 8
What is the foramen primum?
is located between the SP (septum primum) and endocardial cushion
is obliterated when the SP later fuses with the endocardial cushion
What is the foramen secundum?
forms within the upper part of the SP just before the FP closes to maintain the right to left shunting of oxygenated blood that entered the right atrium via the inferior vena cava