Cardiovascular Development Quiz

The first functional organ to develop in the embryo. It arises from the cardiogenic area in the splanchnic mesoderm of the yolk sac, a location cranial to the developing mouth and nervous system and ventral to the pericardial sac.

Paired regions of mesoderm tissue located near the cranial end of the embryo, responsible for the formation of the heart.

Two hollow tubes that fuse together to form the single heart tube. They are derived from the cardiogenic fields and are formed by the canalization of angioplastic cords.

The process of folding an embryo during development, where the cardiogenic fields are brought together in the midline to fuse and form the primitive heart tube.

The process of folding an embryo during development, where the cardiogenic fields are brought from the cranial end towards the center of the embryo, placing them in the thoracic region where the heart will be located.

The first stage of heart development resulting from the fusion of the endocardial heart tubes. It comprises five distinct regions: sinus venosus, truncus arteriosus, bulbus cordis, common ventricle, and common atrium.

The region at the venous end of the primitive heart tube, which is the caudal end.

The region at the arterial end of the primitive heart tube, which is the cranial end.

The sinus venosus is a structure found in the developing heart that acts as a receiving chamber for blood from veins, eventually becoming incorporated into parts of the right and left atria.

The sinus venosus has two horns, the right and left. The right horn becomes the smooth posterior part of the right atrium, while the left horn atrophies and forms the coronary sinus.

The vitelline vein drains the yolk sac, the umbilical vein drains the placenta, and the common cardinal vein drains from the fetal body.

The sinu-atrial orifice is the opening through which the sinus venosus connects to the primitive atrium. It is guarded by two venous valves that fuse to form the septum spurium.

The development of the atria involves numerous steps, including the division of the atrioventricular canal, the formation of the interatrial septum, and the absorption of various structures into the developing atria.

The septum spurium is a temporary structure formed by the fusion of the venous valves guarding the sinu-atrial orifice. It eventually blends with the interatrial septum and disappears in the adult heart.

The right valve of the sinu-atrial orifice gives rise to parts of the crista terminalis, the valve of the inferior vena cava, and the valve of the coronary sinus.

The left common cardinal vein develops into the oblique vein of the left atrium, while the right common cardinal vein forms the lower half of the superior vena cava.

The right atrium develops from a majority of the primitive atrium and a section of the sinus venosus, responsible for receiving blood from the right and left sinus horns.

As the right atrium grows, it absorbs part of the right sinus horn, which ultimately forms the superior and inferior vena cava. The left sinus horn becomes the coronary sinus, responsible for draining venous blood from the heart's own blood vessels.

The left atrium develops from a smaller part of the primitive atrium and the proximal portions of the pulmonary veins. These veins initially start as a single vein entering the left atrium.

The single pulmonary vein is formed from four branches converging to form one vein that drains into the developing left atrium. As the left atrium grows, it absorbs this vein all the way to its four branches.

The atrioventricular canal is a long, narrow passage between the primitive atrium and ventricle. Two endocardial cushions, one on the ventral side and one on the dorsal side, appear and fuse together forming the septum intermedium.

The septum intermedium acts as a divider, separating the canal into the right and left portions. The primitive atrium is divided into right and left chambers by an interatrial septum, but a gap connecting the two atria remains during fetal development.

Septum primum, a crescent-shaped membrane, grows from the roof of the atrium towards the septum intermedium, with a gap called the foramen primum. Before closure, the septum primum ruptures at its center, forming another gap called the foramen secundum.

The upper part of the septum primum attached to the atrium's roof resorbs, forming an opening called the ostium secondum. Another septum, called septum secundum, descends on the right side of the septum primum, ultimately forming the foramen ovale.

The process by which the common bulbo-ventricular chamber is divided into the right and left ventricles.

The muscular part of the heart tissue that grows upwards from the floor of the primitive ventricle towards the endocardial cushions.

A hole in the heart that allows blood to flow between the ventricles before birth.

The thin tissue that grows down from the endocardial cushions to close the primary interventricular foramen, forming the final partition between the ventricles.

The smooth upper part of the right ventricle that leads to the pulmonary trunk.

The smooth upper part of the left ventricle that leads to the ascending aorta.

The tube that connects the heart to the aorta and pulmonary trunk before birth.

The spiral septum that divides the truncus arteriosus into the aorta and pulmonary trunk.

A congenital heart defect characterized by four abnormalities: ventricular septal defect (VSD), pulmonary stenosis, right ventricular hypertrophy, and overriding aorta.

A condition where the aorta and pulmonary artery are transposed (switched). This means oxygen-poor blood flows to the body and oxygen-rich blood flows to the lungs.

The sixth aortic arch develops into the left and right pulmonary arteries. The left artery connects to the ductus arteriosus, while the right loses this connection.

The fourth aortic arch forms the arch of the aorta on the left and the right subclavian artery on the right.

Oxygenated blood enters the fetus through the umbilical vein. It mixes with deoxygenated blood in the inferior vena cava.

The fetal circulation is different from adult circulation. Oxygenated blood reaches the systemic circulation via the umbilical vein.

The fetal circulation bypasses the lungs because the fetus receives oxygen from the placenta. The ductus arteriosus allows blood to flow directly from the pulmonary artery to the aorta.

The ductus venosus allows blood to bypass the developing liver in the fetus, preventing oxygenated blood from being metabolized by the liver and ensuring that the brain receives adequate oxygen.

The foramen ovale allows blood to flow directly from the right atrium to the left atrium, bypassing the pulmonary circulation in the fetus. This is because the lungs are not yet functional, and the fetus relies on the placenta for oxygen.

The ductus arteriosus connects the pulmonary trunk to the aorta, allowing blood to bypass the pulmonary circulation in the fetus. This is because the lungs are not yet functional, and the fetus relies on the placenta for oxygen.

After birth, the ductus arteriosus closes due to increased oxygen levels in the baby's blood and becomes the ligamentum arteriosum. This marks the beginning of the pulmonary circulation taking over oxygenation.

After birth, the foramen ovale closes as the pressure in the left atrium increases due to higher blood flow from the now-functional lungs. It becomes the fossa ovalis.

After birth, the ductus venosus closes as the umbilical cord is cut and blood flow from the placenta ceases. It becomes the ligamentum teres.

The changes in fetal circulation after birth are triggered by the baby's first breath, which increases oxygen levels in the blood, and the cessation of placental blood flow.

Fetal circulatory adaptations ensure that the fetus receives adequate oxygen and nutrients from the placenta while bypassing the lungs, as they are not yet functional. After birth, these structures adapt to facilitate the transition to independent breathing and blood circulation.