test 2 part 2

heart tube is found in ____ mesoderm

splanchnic

as folding occurs, yolk sac cavity gets ____, and amniotic cavity gets ____

smaller, larger

neural tube becomes

brain and spinal cord

this elongates and causes folding to happen

neural tube

embryo grows faster ____ rather than ____

dorsally, ventrally

this overhangs over the heart and causes folding

forebrain

forebrain causes ____ to form

foregut

tail fold caused by

caudal eminence

forebrain overhangs due to closure of

rostral neuropore

folic acid helps with closure of

rostral neuropore

failure of closure of cranial neuropore can cause

anencephaly

notochord determines these two factors:

differentiation of mesoderm, formation of neural plate

failure of closure of caudal neuropore causes

spina bifida

septum transversum comes from

embryonic mesoderm

during folding, the heart tube moves in what direction?

ventrally

two heart tubes fuse to form

one primordial heart

intraembryonic coelom in heart becomes

pericardial cavity

two intraembryonic coeloms fuse to form

one primitive pericardial cavity

atrial septum defect (ASD) is related with what disorder

Down Syndrome

right side of heart (after birth) full of oxygen- or CO2-rich blood?

CO2

left side of heart (after birth) full of oxygen- or CO2-rich blood)?

oxygen

do lungs work before birth?

no - oxygen is supplied by umbilical vein

the heart forms from the ____ mesoderm, found under ____ ____

splanchnic, intraembryonic coelom

heart comes from ____ ____ ____

two endocardial tubes

what is the first major system to form in the embryo?

cardiovascular

esophagus forms between ____ and ____

heart, dorsal aorta

rough part of atrium called

primitive atrium

rough part of ventricle called

primitive ventricle

smooth part of atrium called

sinus venosus

smooth part of ventricle called

bulbus cordis

truncus arteriosus becomes

pulmonary trunk artery (in blue like vein) and ascending aorta AFTER BIRTH

do the aortic sac and truncus arteriosus contribute to actual heart or blood vessels?

blood vessels

separation of aorta and pulmonary trunk artery caused by

neural crest cells

if the truncus arteriosus and aorta don’t separate after birth, what occurs

disease name is truncus arteriosus (TA) and surgery must be performed

order of blood flow in primituve heart

bulbus cordis, aortic sac, pharyngeal arch arteries, dorsal aortae

EXTERNALLY, bulbus cordis attributes to

smooth outflow portion of L and R ventricles

EXTERNALLY, primitive ventricle attributes to

trabeculated part of L and R ventricles

the right and left ventricles arise from the

primitive ventricle and bulbus cordis

primitive atrium becomes

rough part of atrium, aka the auricles

atrium moves in what direction during cardiac looping?

cephalically, up

primitive atrium partially encircles the

bulbus cordis

smooth part of right atrium comes from

right horn of sinus venosus

blood in the posterior side of heart is flowing ____, in the anterior side, it is flowing ____

down, up

sinus venosus can only be seen by

a dorsal view into atrium

which of the 5 regions of the primitive heart has two horns?

sinus venosus

right horn of sinus venosus contributes to the ____ node and incorporates into smooth part of right atrium, aka ____ ____

SA, sinus venarum

left horn of sinus venosus becomes

coronary sinus

smooth part of left atrium comes from

common pulmonary veins

common pulmonary veins arise from

lung buds

common pulmonary vein gives rise to left and right

pulmonary veins

venous blood enters the heart through

horns of sinus venosus, three differemt veins

left and right atria arise from

primitive atrium and sinus venosus

coronary sinus is derived from

left horm of sinus venosus

conus arteriosus is derived from where?

bulbus cordis - CONUS ARTERIOSUS IS AFTER BIRTH

epicardium of primitive heart tube is derived from

embryonic splanchnic layer of lateral mesoderm

epicardium of primitive heart tube is also known as

visceral pericardium aka serosa

fibrous pericardium comes from

septum trasnversum

these make cardiac jelly

myoblasts

myocardium slowly replaces

cardiac jelly of heart

myocardium of primitive heart tube is derived from

embryonic splanchnic layer of lateral mesoderm

cardiac jelly consists of this

hyalauronic acid, GAGs, collagen fibers, and water-rich gelatinous ground substance

cardiac jelly separates these two structures

endocardium from myocardium

most of the thickness of the heart wall comes from

cardiac jelly

cardiac jelly is replaced by this

myocardium

cardiac jelly forms this by EMT

endocardial cushion

myocardium secretes ____, which attaches to the endocardium

EMT protein

endocardial cells undergo ____ , which then makes the ____ ____

EMT, endocardial cushion

myoblasts make

cardiac jelly

what is the role of endocardial cushions?

cellular deposits extending from sides of endocardial tubes that develop into septums

neural crest cells form these two structures in endocardial cushion

bulbar and truncal ridges

partial separation in ____ ____ to allow blood flow from atrium to ventricle

endocardial cushion

endocardium of primitive heart tube is derived from

splanchnic embryonic mesoderm

if no AV endocardial cushion forms, what birth defect arises?

AVSD - related with Down Syndrome

ventricular myocardium underneath cushions undergoes ____ to make AV valves

excavation

tricuspid atresia occurs when this function does not happen

excavation of myocardial walls in ventricle

Ebstein’s anomaly caused by

displaced valve, causes atrializing ventricle - should be ventricle, but it becomes atrium

septum primum grows in what direction

down

septum primum fuses ____ ____

endocardial cushion

septum primum contains the first ____

opening

upper part of septum primum undergoes ____ to form second opening

apoptosis

primitive ventricle gives rise to

trabeculated part of L and R ventricles

septum primum comes from

EMT

septum secundum is derived from

sinus venosus

septum secundum forms on which side of the septum primum

right

fossa ovalis forms bc of the fusion of these two structures

septum primum, septum secundum

muscular part of interventricular septum forms from ____ cells in primitive ventricle

myoblast

all 4 valves come from

endocardial cushion, also septum primum