Cardiovascular System Flashcards

Right atrium, right ventricle, left atrium, and left ventricle. Atria receive blood; ventricles pump it out.

Vena cavae -> right atrium -> right ventricle -> pulmonary arteries -> lungs -> pulmonary veins -> left atrium -> left ventricle -> aorta -> body.

Pulmonary circulation carries deoxygenated blood from the right ventricle to the lungs and returns oxygenated blood to the left atrium. Systemic circulation delivers oxygenated blood from the left ventricle to the body.

Tricuspid (right AV), mitral/bicuspid (left AV), pulmonary semilunar (right ventricle outflow), and aortic semilunar (left ventricle outflow).

They prevent backflow of blood, ensuring unidirectional flow through the heart chambers and into the great vessels.

SA node -> AV node -> Bundle of His -> right and left bundle branches -> Purkinje fibers. The SA node is the primary pacemaker.

Systole (ventricular contraction, ejecting blood) and diastole (ventricular relaxation, filling with blood). One full cycle is one heartbeat.

The volume of blood pumped by one ventricle per minute. CO = heart rate x stroke volume. Normal resting CO is approximately 5 L/min.

Arteries (carry blood away from the heart), veins (return blood to the heart), and capillaries (exchange gases, nutrients, and wastes with tissues).

Arteries have thicker, more elastic, muscular walls to withstand high pressure. Veins have thinner walls and contain valves to prevent backflow.

The force blood exerts on vessel walls. Systolic is peak pressure during ventricular contraction; diastolic is lowest pressure during relaxation. Normal: ~120/80 mmHg.

Tunica intima (inner endothelium), tunica media (smooth muscle and elastic tissue), and tunica adventitia/externa (outer connective tissue).

Plasma (~55%), red blood cells (erythrocytes), white blood cells (leukocytes), and platelets (thrombocytes). Plasma is mostly water with dissolved proteins.

To transport oxygen from the lungs to tissues and carry carbon dioxide back to the lungs, using the protein hemoglobin.

Platelets are cell fragments that initiate clot formation at injury sites by aggregating and releasing clotting factors, preventing excessive blood loss.

The heart contracts more forcefully when its ventricles are stretched by greater blood volume, increasing stroke volume to match venous return.

Oxygenated blood to the myocardium (heart muscle) itself. Blockage of a coronary artery causes a myocardial infarction (heart attack).