Embryonic Development of the Cardiovascular System

Question 1

What kind of tissue is the cardiovascular system derived from?

Answer 1

Angioblastic, it arises from the mesenchyme

Question 2

Process of blood vessel development

Answer 2

Angiogenesis

Question 3

T/F: The cardiovascular system is the first functional system in the embryo.

Answer 3

True

Question 4

Cardiogenic field

Answer 4

Horshoe-shaped structure located around the anterior and lateral portions of the neural plate; an area of blood-forming cavities in the visceral mesoderm where hemangioblasts will eventually coalesce and form the primitive heart, blood vessels, and blood cells (cardiogenic cords –> endocardial heart tubes)

Question 5

What gives rise to the heart and dorsal and ventral aortas?

Answer 5

The caudal portions of the endocardial heart tubes; the tubes are first composed of only endothelial cells; the caudal portion then fuses and becomes surrounded by myoblasts to form the myocardium –> formation of the cardiac tube

Question 6

Describe the components of this picture

Answer 6

The cardiac tube is composed of the bulbus cordis (10) precursor of the right ventricle, ventricle (11) and atrium (12) which joins the venous system; later on loop formation occurs, the process that in conjunction with the relative complex division of the cardiac tube into 4 chambers (partitioning of the primitive heart) will result in the formation of the blood pumping organ necessary for the survival of the neonate

Question 7

Describe the partitioning of the atrio-ventricular canal

Answer 7

• Primitive atrium divided into left and right atria
• Primitive ventricle divided into left and right ventricles
• Truncus arteriosus divided into outflow tracts of aorta and pulmonary trunk

Question 8

Describe the truncus arteriosus

Answer 8

Divided into ascending aorta and pulmonary trunk by a spiral septum; this septum is made up of two ridges which have varying positions in the different parts of truncus arteriosus

Question 9

What develops when the two ridges of the truncus arteriosus fuse?

Answer 9

The aorto-pulmonary septum; the spiral formation of the septum ensures that blood from the right ventricle flows into the pulmonary trunk and that the blood from the left ventricle flows into the ascending aorta

Question 10

Can someone live with transposition of the great vessels?

Answer 10

No, deoxygenated blood from the right ventricle flows into the ascending aorta and the highly oxygenated blood from the left ventricle flows into the pulmonary trunk (lungs)

Question 11

Picture of a normal heart

Answer 11

Question 12

Persistent foramen ovale

Answer 12

Atrial septic defect (view from left atrium in neonatal pig)

Question 13

Patent ductus arteriosus

Answer 13

One of the most common congenital anomalies in domestic animals

Question 14

Persistent right aortic arch (PRAA)

Answer 14

Leads to megaesophagus, animals often die of aspiration pneumonia