Circulation - CEN Review

Cardiac output is the amount of blood pumped by the heart per minute. It is calculated by multiplying the heart rate (HR), which is the number of times the heart beats per minute, with the stroke volume (SV), which is the amount of blood pumped by the heart with each beat. Therefore, the correct answer is HR and Stroke Volume.

Pulse pressure (pp) is the difference between the systolic and diastolic pressure. It is calculated by subtracting the diastolic pressure from the systolic pressure. Pulse pressure is an important measure because it reflects the force that the heart generates each time it contracts. It provides information about the elasticity and compliance of the arteries, and can be an indicator of cardiovascular health. A wider pulse pressure may indicate increased arterial stiffness or hypertension, while a narrower pulse pressure may suggest decreased cardiac output or other cardiovascular issues.

During ventricular diastole, the heart is in a relaxed state. The "Lub" heart sound occurs during ventricular diastole when the atrioventricular (AV) valves close. This sound is produced by the closure of the mitral and tricuspid valves, preventing the backflow of blood from the ventricles into the atria. The closure of these valves marks the beginning of ventricular diastole and the start of the filling phase of the cardiac cycle. Therefore, the Lub heart sound is the correct answer as it accurately describes an event that occurs during ventricular diastole.

The subclavian vein is not considered a tributary of the portal vein because it drains blood from the upper extremities and does not contribute to the hepatic portal system. The other options, the inferior mesenteric vein, splenic vein, and left gastric vein, are all tributaries of the portal vein and play a role in draining blood from the digestive organs and spleen into the liver.

Prothrombin is a type of globulin that is produced by the liver. The liver is responsible for synthesizing many proteins, including prothrombin.

Inside the cranial cavity, the vertebral arteries merge together to form the basilar artery. The basilar artery is responsible for supplying blood to the brainstem, cerebellum, and the posterior cerebral hemispheres. This artery plays a crucial role in maintaining proper blood flow and oxygenation to these regions of the brain.

Pulmonary edema is the accumulation of fluid in the lungs, which occurs when the left ventricle of the heart fails to pump blood effectively. The left ventricle is responsible for pumping oxygenated blood from the lungs to the rest of the body. When it fails to do so, blood backs up into the left atrium and then into the lungs, causing fluid to leak into the lung tissue. Therefore, pulmonary edema is most commonly associated with a failing left ventricle.

The celiac artery is responsible for creating the left splenic, hepatic, and gastric arteries. It is a major branch of the abdominal aorta and supplies blood to the upper abdominal organs. The left sacral artery, suprarenal artery, and phrenic artery do not have any direct involvement in supplying blood to these specific arteries.

Blood flowing into the cardiac veins enters the coronary sinus next. The coronary sinus is a large vein located on the posterior side of the heart that collects deoxygenated blood from the cardiac veins. This blood is then transported into the right atrium of the heart, where it will eventually be pumped into the lungs for oxygenation.

The brachiocephalic artery is a major branch of the aorta that supplies blood to the head and neck. It divides into two branches: the right common carotid artery and the right subclavian artery. The right subclavian artery continues down the right side of the body, supplying blood to the right arm and other structures in the upper chest. Therefore, the correct answer is the right subclavian artery.

Angiotensin is a hormone that plays a crucial role in regulating blood pressure. It is produced in response to low blood pressure or low blood volume. One of the main functions of angiotensin is to stimulate the release of aldosterone from the adrenal cortex. Aldosterone is a hormone that acts on the kidneys to increase the reabsorption of sodium and water and excretion of potassium. This helps to increase blood volume and therefore increase blood pressure. Therefore, the correct answer is Aldosterone.

During ventricular systole, the ventricles of the heart contract and pump blood out into the aorta and pulmonary artery. This contraction results in an increase in aortic pressure as the blood is forcefully ejected from the left ventricle into the aorta. The other options, such as increased ventricular volume, dub heart sound, and P wave, are not directly associated with ventricular systole.

Accelerator nerves can be found joining the SA and AV nodes in the heart. These nerves are responsible for increasing the heart rate and enhancing the force of contraction. When the accelerator nerves are stimulated, they release norepinephrine, which binds to receptors in the heart and causes an increase in heart rate. This helps to regulate the heart's rhythm and ensure efficient blood flow throughout the body.

The innermost layer of a blood vessel is lined with simple squamous cells. This type of epithelium consists of a single layer of flat cells that allow for easy diffusion of substances across the vessel wall. Simple squamous epithelium is well-suited for this function due to its thinness and ability to facilitate the exchange of gases, nutrients, and waste products between the blood and surrounding tissues.

The mediastinal artery is not considered a major branch off the abdominal aorta. The abdominal aorta gives rise to several major branches, including the phrenic artery, common iliac artery, and gonadal artery. However, the mediastinal artery is not typically considered a major branch off the abdominal aorta.

The right coronary artery divides to form the posterior interventricular artery and the marginal artery.

The brachiocephalic artery is the first branch off the aortic arch. It is responsible for supplying blood to the right subclavian artery, the right common carotid artery, and the right side of the head and neck. The other options listed, such as the common carotid artery, right subclavian artery, and thoracic artery, are not the first branches off the aortic arch.

The tricuspid valve is located on the right side of the heart, between the right atrium and the right ventricle. To detect the tricuspid valve using a stethoscope, the best location would be on the left side of the sternum near the midpoint. This is because the sound of the tricuspid valve can be heard most clearly in this area, allowing for accurate detection.

The mediastinal artery is not considered a major branch off the descending thoracic aorta. The descending thoracic aorta gives rise to several major branches, including the renal artery, bronchial artery, and posterior intercostal artery. However, the mediastinal artery is not typically listed as one of the major branches off the descending thoracic aorta.

The deep external pudendal arteries are not considered a major branch off of the femoral artery. The femoral artery gives rise to several branches, including the superficial pudendal arteries, superficial circumflex iliac artery, and deep circumflex iliac artery. However, the deep external pudendal arteries are not among these major branches.