Block 3 The Vessels Practice MCQ's - The Cardiovascular System (II)

The common carotid arteries are derived from the third aortic arches. The aortic arches are embryonic structures that give rise to major arteries in the body. The third aortic arches specifically develop into the common carotid arteries, which are responsible for supplying blood to the head and neck. Therefore, the correct answer is common carotid arteries.

In the adult, the foramen ovale becomes the oval fossa. This is because the foramen ovale is a small opening in the fetal heart that allows blood to bypass the lungs. After birth, when the lungs become functional, the foramen ovale closes and eventually forms a depression in the wall of the heart called the oval fossa. The oval fossa is a remnant of the foramen ovale and is a normal anatomical feature in adults.

Patent ductus arteriosus is very common in premature infants. The ductus arteriosus is a blood vessel that connects the pulmonary artery to the aorta during fetal development. In premature infants, this ductus fails to close after birth, resulting in a patent ductus arteriosus. This condition can lead to abnormal blood flow between the aorta and the pulmonary artery, causing symptoms such as difficulty breathing and poor feeding. Treatment may involve medication or surgical intervention to close the ductus.

The hepatic sinusoids in an adult liver are derived from the vitelline veins. During embryonic development, the vitelline veins carry blood from the yolk sac to the developing liver. These veins eventually form the hepatic sinusoids, which are specialized blood vessels in the liver that allow for the exchange of nutrients, waste products, and hormones between the blood and liver cells. Therefore, the correct answer is vitelline veins.

The superior vena cava is formed by the merging of the right anterior cardinal vein and the right common cardinal vein during embryological development. These vessels eventually give rise to the major vessel that drains blood from the head and neck.

The course of the adult recurrent laryngeal nerves differs on the two sides due to differences in the transformation of the sixth aortic arch arteries. In the case of the right recurrent laryngeal nerve, it hooks around the right subclavian artery. This is because of the specific anatomical arrangement of the structures in that area. The right subclavian artery is located in close proximity to the right recurrent laryngeal nerve, causing it to take a different course compared to the left recurrent laryngeal nerve.

The left umbilical vein persists and delivers blood from the placenta to the developing fetus.

The fetal left atrium receives blood from the right atrium. During fetal development, oxygenated blood from the placenta enters the fetus through the umbilical vein and is directed towards the liver. From there, the blood flows into the inferior vena cava and then into the right atrium. The right atrium then pumps the blood into the left atrium through the foramen ovale, a hole in the septum between the two atria. This allows oxygenated blood to bypass the lungs, which are non-functional in the fetus, and reach the rest of the body.

The superior mesenteric artery is derived from the vitelline arterial plexus. The vitelline arterial plexus is a network of blood vessels that forms during embryonic development and supplies blood to the developing intestines. As the embryo grows, the vitelline arterial plexus gives rise to several major arteries, including the superior mesenteric artery. This artery provides blood supply to the midgut, which includes parts of the small intestine, cecum, appendix, and ascending colon.

In the fetus, the ductus venosus shunts approximately half of the blood flow of the umbilical vein directly to the inferior vena cava. Thus, it allows oxygenated blood from the placenta to bypass the liver.