Cardiopulmonary Development

Question 1

where is the laryngotracheal groove located?

Answer 1

caudal to 4th pair of pharyngeal pouches

Question 2

the endoderm is the embryonic origin of what structures?

Answer 2

epithelium, glands of larynx, trachea, bronchi, lungs

Question 3

the splanchnic mesoderm is the embryonic origin of what structures?

Answer 3

connective tissue, cartilage, smooth muscle

Question 4

what forms from the respiratory diverticulum?

Answer 4

lung bud

Question 5

when does the respiratory diverticulum appear?

Answer 5

end of 4th week

Question 6

what does the visceral pleura develop from?

Answer 6

splanchnic mesenchyme

Question 7

what does the parietal pleura develop from?

Answer 7

somatic mesoderm

Question 8

what do the primary bronchial buds grow laterally into?

Answer 8

pericardioperitoneal canals

Question 9

what do the primary bronchial buds differentiate into? with what embryonic layer?

Answer 9

bronchi

splanchnic mesenchyme

Question 10

primary bronchial buds are the primordium (origin) of what structure in the tracheobronchial tree?

Answer 10

main bronchus

Question 11

when is the pseudoglandular period?

Answer 11

6-16 wks

Question 12

what are defining characteristics of the pseudoglandular period?

Answer 12

resembles exocrine gland, no gas exchange

Question 13

when is the canalicular period?

Answer 13

16-26 wks

Question 14

what are defining characteristics of the canalicular period?

Answer 14

lumina of bronchi and bronchioles form, formation of alveolar ducts and terminal saccules, well-vascularized, some gas exchange possible

Question 15

when is the terminal saccular period?

Answer 15

26 wks - birth

Question 16

what are defining characteristics of the terminal saccular period?

Answer 16

more terminal saccules develop, thin alveolar walls, surfactant is secreted

Question 17

when is the alveolar period?

Answer 17

32 wks - 8 yrs

Question 18

what are defining characteristics of the alveolar period?

Answer 18

most of alveoli develop (95% postnatally), tremendous increase in alveoli and capillaries

Question 19

heart and vessels are derived from what embryonic structures?

Answer 19

splanchnic mesoderm, paraxial and lateral mesoderm, neural crest

Question 20

what forms from the cardiogenic mesoderm?

Answer 20

angioblastic cords, heart tubes

Question 21

the umbilical arteries will later become parts of which arteries?

Answer 21

internal iliac artery, superior vesical artery

Question 22

what is the function of the umbilical artery?

Answer 22

carry deoxygenated blood to placenta

Question 23

the vitelline arteries will later become which arteries?

Answer 23

celiac trunk, superior mesenteric artery, inferior mesenteric artery

Question 24

the dorsal intersegmental arteries will later become which arteries?

Answer 24

vertebral arteries, intercostal arteries, lumbar arteries, common iliac arteries, lateral sacral arteries

Question 25

where does the heart and great vessels develop from in the embryo?

Answer 25

aortic sac

Question 26

what are the first recognizable vessels in an embryo? what do they form?

Answer 26

paired dorsal aortae single dorsal aorta

Question 27

where does the heart begin to develop?

Answer 27

cardiogenic area

Question 28

what are the angioblastic cords? how do they form? where are they?

Answer 28

endocardial heart tubes fuse with lateral folding superior to endocardium

Question 29

what layer of the embryonic heart is separated from the heart tube by cardiac 'jelly'? what does this become in the adult heart?

Answer 29

primordial myocardium myocardium

Question 30

what is the external surface of the sinus venosus?

Answer 30

epicardium

Question 31

elongation/bending of the heart tube leads to what structure that connects the ventricles to the aortic sac and aortic arches?

Answer 31

truncus arteriosus

Question 32

what embryonic structure will form the right ventricle?

Answer 32

bulbus cordis

Question 33

what embryonic structure will form the left ventricle?

Answer 33

bulboventricular loop

Question 34

what structures are dorsal on the embryonic heart?

Answer 34

atrium, sinus venosus

Question 35

what structures are ventral on the embryonic heart?

Answer 35

truncus arteriosus, ventricle

Question 36

what area does the heart tube fold into?

Answer 36

pericardial cavity

Question 37

what structures develop away from the embryonic heart?

Answer 37

dorsal aorta

Question 38

what structures develop towards the embryonic heart?

Answer 38

common cardinal veins (to embryo), umbilical veins (to placenta), vitelline veins (to yolk sac)

Question 39

the first heart beat is also known as what of the sinus venosus, atrium, and ventricle?

Answer 39

peristaltic contractions

Question 40

the ventricle leads to what structures?

Answer 40

bulbus cordis, truncus arteriosus, aortic arch

Question 41

when does partitioning of the primordial heart occur?

Answer 41

end of 4th wk

Question 42

what structure lies within the atrioventricular canal?

Answer 42

endocardial cushions

Question 43

what is the function of the endocardial cushions? how and where do they form?

Answer 43

form valves and membranous septa fuse and divide AV canal into right-left sides by forming from the dorsal to ventral walls of the AV canal

Question 44

the primordial atrium is separated by what two structures?

Answer 44

septum primum, septum secundum

Question 45

what does the septum primum do to separate the atria into right and left halves?

Answer 45

grows toward the endocardial cushions

Question 46

what is the foramen primum? what is its function?

Answer 46

opening between crescentic edge and endocardial cushions shunts blood from right to left atrium

Question 47

what occurs when the septum primum fuses with the endocardial cushions?

Answer 47

foramen primum disappears

Question 48

what is the foramen secundum? what is its function?

Answer 48

performations in the central part of the septum primum shunts blood from right to left atrium

Question 49

where does the septum secundum grow? what is its function?

Answer 49

to the right of the septum primum covers foramen secundum as a flap valve to create the oval foramen

Question 50

what are the pressures in the atria before birth?

Answer 50

right - high pressure left - low pressure

Question 51

what are the pressures in the atria after birth?

Answer 51

right - low pressure left - high pressure

Question 52

what are the main changes to the sinus venosus during embryonic heart development?

Answer 52

enlargement of right horn, left horn becomes smaller

Question 53

what occurs from the enlargement of the right horn of the sinus venosus?

Answer 53

shunt becomes left to right, will become wall of right atrium

Question 54

what occurs from the smaller left horn of the sinus venosus?

Answer 54

will become coronary sinus

Question 55

the primary pulmonary vein will develop during embryonic heart development - what is it an outgrowth of?

Answer 55

dorsal atrial wall

Question 56

the primary pulmonary vein will become incorporated into what structure?

Answer 56

wall of left atrium

Question 57

what forms to partition the primordial ventricle?

Answer 57

primordial interventricular septum

Question 58

how does the primordial interventricular septum form? what does it form?

Answer 58

crescentic fold from floor of ventricle forms muscular part of septum

Question 59

where is the interventricular foramen? what occurs to close this space?

Answer 59

between IV septum and fused endocardial cushions closed by fusion of bulbar ridges and endocardial cushions

Question 60

where is the membranous part of the septum?

Answer 60

between right side of endocardial cushion to IV septum

Question 61

the bulbar ridges and truncal ridges develop from what embryonic cells?

Answer 61

neural crest mesenchyme

Question 62

what is the name of the right bulbus cordis after partitioning?

Answer 62

conus arteriosus

Question 63

what is the name of the left bulbus cordis after partitioning?

Answer 63

aortic vestibule

Question 64

during the partitioning of the bulbus cordis and truncus arteriosus, the bulbar ridges and truncal ridges spiral, creating what structure? what vessels does this form?

Answer 64

aorticopulmonary septum aorta, pulmonary trunk

Question 65

what develops from the swellings of the subendocardial tissue?

Answer 65

semilunar and AV valves

Question 66

what are the four main types of anomalies of the heart and great vessels?

Answer 66

atrial septal defects, ventricular septal defects, transposition of great arteries, tetralogy of fallot

Question 67

what are types of atrial septal defects?

Answer 67

patent oval foramen, ostium secundum defect, endocardial cushion defect with ostium primum defect, sinus venosus defect, common atrium

Question 68

what are types of ventricular septal defects?

Answer 68

membranous ventricular septal defect, muscular ventricular septal defect

Question 69

which septal defect is known as "swiss cheese vsd?"

Answer 69

muscular ventricular septal defect

Question 70

what leads to transposition of the great arteries?

Answer 70

linear septation so that the pulmonary artery and aorta are coming off the wrong chambers

Question 71

what is tetralogy of fallot?

Answer 71

type of ventricular septal defect that causes pulmonary stenosis, leading to dextroposition of aorta and right ventricular hypertrophy

Question 72

fetal blood circulation occurs through which vein?

Answer 72

umbilical vein

Question 73

what vessels does the umbilical vein drain into?

Answer 73

ductus venosus, inferior vena cava

Question 74

during fetal circulation, what where does the inferior vena cava shunt blood?

Answer 74

left atrium, left ventricle, aorta

Question 75

what happens to the small amount of blood in the right atrium and right ventricle during fetal circulation?

Answer 75

ductus arteriosus

Question 76

what parts of the body receive well-oxygenated blood after fetal circulation?

Answer 76

heart, head, neck, upper limbs

Question 77

what four main events occur in neonatal circulation?

Answer 77

aeration of lungs, oval foramen closes, ductus arteriosus constricts, umbilical arteries constrict

Question 78

what occurs due to aeration of lungs in neonatal circulation?

Answer 78

fall in pulmonary vascular resistance (increase in pulmonary blood flow), thinning of walls of pulmonary arteries