Circulatory System Quiz

The inelastic layer of the pericardium is the fibrous pericardium, which is a tough, protective outer layer. It helps to prevent the heart from overstretching and protects it from injury.

The serous pericardium has two layers: the parietal layer, which lines the inner surface of the fibrous pericardium, and the visceral layer, which wraps around the heart and forms the epicardium.

The muscle layer of the heart is called the myocardium. The myocardium is responsible for pumping blood throughout the body.

The pericardial cavity is a small space filled with pericardial fluid, which acts as a lubricant for the heart's movements. It's located between the parietal and visceral layers of the serous pericardium.

Pericardial fluid is the lubricating fluid found in the pericardial cavity. It helps to reduce friction as the heart beats.

Pericarditis is inflammation of the pericardium, the sac surrounding the heart. It can cause chest pain and difficulty breathing.

If fluid collection in the pericardial cavity increases, it can compress the heart, leading to a condition called cardiac tamponade. This can reduce the heart's ability to pump blood effectively.

The right atrium receives deoxygenated blood from the body through the superior and inferior vena cava, and the coronary sinus.

The tricuspid valve controls blood flow between the right atrium and right ventricle.

The right ventricle pumps deoxygenated blood to the lungs through the pulmonary valve.

The left atrium receives oxygenated blood from the lungs through four pulmonary veins (two superior, two inferior).

The mitral valve controls blood flow between the left atrium and left ventricle.

The left ventricle pumps oxygenated blood to the body through the aortic valve.

The 'lubb' sound is caused by the closure of the mitral and tricuspid valves at the beginning of ventricular contraction (systole).

The 'dupp' sound is caused by the closure of the aortic and pulmonary valves at the beginning of ventricular relaxation (diastole).

The smallest blood vessels where exchange of oxygen, nutrients, waste products, and other substances between the blood and tissues occurs.

Thin-walled vessels that collect blood from capillary beds and drain into larger veins.

Blood vessels that carry oxygen-rich blood away from the heart to the body.

Large arteries with abundant elastic fibers, allowing them to stretch and recoil with each heartbeat, smoothing blood flow.

Medium-sized arteries with more muscle fibers, enabling them to constrict and dilate, regulating blood flow.

The innermost layer of a blood vessel, composed of endothelium, which forms a smooth lining for blood flow.

The middle layer of a blood vessel, primarily composed of smooth muscle, which controls vessel diameter and blood pressure.

The outermost layer of a blood vessel, composed of connective tissue that anchors the vessel to surrounding tissues.

Tiny blood vessels that supply oxygen and nutrients to the walls of larger blood vessels, like arteries and veins.

Small nerve bundles that control vasoconstriction and vasodilation in blood vessels.

Connections between branches of an artery that create alternate pathways for blood flow.

An alternate blood flow route when the main path is blocked.

Arteries that do not have any connections with neighboring arteries.

Narrowing of a blood vessel.

Hardening of the arteries due to thickening and loss of elasticity in the arterial walls.

A condition where the arteries stiffen and lose their ability to stretch and relax.

A venous system where blood travels through two capillary beds before returning to the heart.

The hepatic portal system is an example of a portal venous system where blood rich in nutrients from the digestive tract flows through capillary beds in the liver before returning to the heart.

Veins carry deoxygenated blood from the capillary beds back to the heart. They have thinner walls than arteries due to lower blood pressure.

Veins don't pulsate as arteries do, and they don't squirt blood when cut. They have a larger diameter than arteries and store about 80% of the body's blood.

The smallest veins that collect blood from capillary beds.

Medium-sized veins that run alongside arteries and have valves to ensure one-way blood flow towards the heart.

Large veins that collect blood from smaller veins and transport it to the heart. Examples include the superior and inferior vena cava.

Veins that accompany arteries and form a network around them, helping to regulate blood flow and body temperature.

The lymphatic system's main drainage channel, collecting lymph from most of the body.

A dilated collecting pouch formed by the merging of lymphatic trunks in the abdomen. It may not always be present, but it's a common site for lymph to collect in the lower body before flowing to the thoracic duct.

The location where the thoracic duct empties into the circulatory system, specifically the junction of the left internal jugular and left subclavian veins.

The fluid contained within the lymphatic system, derived from interstitial fluid and similar in composition to blood plasma but with less protein.

Small, bean-shaped masses of lymphatic tissue situated along lymphatic vessels, filtering lymph and containing immune cells.

White blood cells that circulate in the blood and lymphatic system, vital for identifying and fighting foreign invaders.

Organs involved in producing lymphocytes, including the thymus, red bone marrow, spleen, tonsils, and lymphoid tissue in the gut.

Tiny, specialized vessels that collect interstitial fluid from tissues and transport it into larger lymphatic vessels.