Human Circulation Quiz

The outer layer of the heart which is part of the serous pericardium.

The middle layer of the heart wall made of cardiac muscle responsible for pumping blood.

The inner layer of the heart wall lining the chambers and valves, made of simple squamous epithelium and areolar tissue.

The groove found around the heart separating the atria from the ventricles.

The groove on the surface of the heart dividing the right and left ventricles.

A sac that surrounds the heart, providing a protective barrier.

The layer of the pericardium that is directly attached to the heart, essentially the epicardium.

The outer layer of the pericardium that lines the pericardial cavity.

The pulmonary circuit moves deoxygenated blood from the right side of the heart to the lungs for oxygenation and then back to the heart.

The systemic circuit carries oxygenated blood from the left side of the heart throughout the body and returns deoxygenated blood back to the heart.

Coronary circulation refers to the blood supply to the heart muscle itself.

The left and right coronary arteries branch out from the base of the aorta, supplying blood to the heart muscle. They are named for their location relative to the aorta.

The coronary blood vessels form a network that distributes oxygenated blood to the heart's muscle tissue.

The grooves on the outer surface of the heart that mark the divisions between the chambers.

The groove running vertically on the front of the heart separating the right and left ventricles.

The groove running vertically on the back of the heart separating the right and left ventricles.

The large blood vessels that connect directly to the heart, transporting blood to and from the lungs and the rest of the body.

The superior and inferior vena cavae carry deoxygenated blood from the body to the right atrium of the heart.

The pulmonary trunk carries deoxygenated blood from the right ventricle to the lungs.

The pulmonary veins carry oxygenated blood from the lungs to the left atrium of the heart.

The aorta carries oxygenated blood from the left ventricle to the rest of the body.

The heart is divided into left and right sides by septa, which are internal walls dividing the chambers.

The septum that separates the two upper chambers of the heart, the atria.

The septum that separates the two lower chambers of the heart, the ventricles.

The upper chambers of the heart that receive blood, collecting it before pumping it to the ventricles.

The right atrium receives deoxygenated blood from the vena cavae and coronary sinus.

The left atrium receives oxygenated blood from the pulmonary veins.

The lower, thicker-walled chambers of the heart that pump blood out.

The left ventricle pumps oxygenated blood to the aorta, which carries it to the entire body.

The right coronary artery supplies blood to the right atrium, portions of both ventricles, and parts of the heart's electrical conduction system, including the SA and AV nodes.

The marginal arteries branch off the right coronary artery and extend across the surface of the right ventricle.

The posterior interventricular artery originates from the right coronary artery and runs along the groove between the ventricles on the back of the heart. It provides blood to the septum separating the ventricles and parts of both ventricles.

The left coronary artery is the major artery supplying the left side of the heart. It branches into the circumflex artery and the anterior interventricular artery.

The circumflex artery is a branch of the left coronary artery that circles around the back of the heart. It eventually connects with small branches of the right coronary artery.

The anterior interventricular artery, a branch of the left coronary artery, runs along the front groove between the ventricles. It connects with the posterior interventricular artery, forming a network of blood supply.

The great cardiac vein collects blood from the area supplied by the anterior interventricular artery and empties into the coronary sinus, which then leads into the right atrium.

The anterior cardiac vein drains blood from the front surface of the right ventricle and empties directly into the right atrium.

The posterior cardiac vein collects blood from the area supplied by the circumflex artery and flows into the great cardiac vein.

The middle cardiac vein collects blood from the area supplied by the posterior interventricular artery and empties into the coronary sinus.

The sinoatrial (SA) node is the heart's natural pacemaker, generating electrical impulses that trigger heart contractions.

The SA node initiates the electrical impulse that travels through the heart's conduction system, causing the heart to beat.

The AV node is a cluster of specialized cells that delay the electrical impulse briefly before sending it to the ventricles, allowing the atria to finish contracting before the ventricles begin.

The AV bundle (Bundle of His) transmits the electrical impulse from the AV node to the ventricles, effectively relaying the signal to the lower chambers of the heart.

The Purkinje fibers are specialized fibers located in the walls of the ventricles that distribute the electrical impulse to the entire ventricular muscle, triggering coordinated contraction.

Arteries are blood vessels that carry oxygenated blood away from the heart, supplying oxygen and nutrients to the body's tissues.

Veins are blood vessels that carry deoxygenated blood back to the heart, bringing waste products for removal.

Capillaries are the smallest blood vessels, forming a network that allows for exchange of gases, nutrients, and waste products between the blood and body tissues.

The innermost layer of a blood vessel is the tunica intima, made of endothelial cells, providing a smooth surface facilitating blood flow.

The middle layer of a blood vessel, the tunica media, is predominantly composed of smooth muscle cells, allowing for vasoconstriction and vasodilation to regulate blood pressure.

Largest arteries located close to the heart. Contain a large amount of elastic fibers in their tunica media, allowing them to stretch and recoil with each heartbeat. This elasticity helps maintain blood pressure and flow.

Medium-sized arteries that distribute blood to specific organs and tissues like skeletal muscles and internal organs. Have a thicker tunica media compared to elastic arteries, primarily composed of smooth muscle, allowing for more precise control of blood flow.

Smallest arteries that connect to capillaries. Their tunica media is mainly made up of smooth muscle, allowing for regulation of blood flow and resistance.

Microscopic blood vessels, the smallest in the circulatory system, responsible for the exchange of oxygen, nutrients, and waste products between blood and the surrounding tissues. They are only one cell layer thick to facilitate diffusion.

Most common type of capillary, featuring a continuous layer of endothelial cells with tight junctions. They are found in most tissues and regulate the passage of substances through their walls.

Capillaries that have small pores or 'windows' in their endothelial lining, allowing for rapid exchange of water, solutes, and small peptides. Often found in organs like kidneys, intestines, and endocrine glands.

The inner lining of a blood vessel, directly facing the blood flow. Made of simple squamous epithelium, it plays a crucial role in regulating blood flow and preventing blood clotting.

The middle layer of a blood vessel. Composed of varying amounts of smooth muscle and elastic fibers, it controls the vessel's diameter and regulates blood pressure.