CLASSWORK : Ch. 7.8 Circulatory System Key Terms
Aortic valve
1. Aortic valve: A heart valve located between the left ventricle and the aorta that prevents the backflow of oxygenated blood into the ventricle.
Arrhythmias
2. Arrhythmias: Irregular heartbeats, which can present as a fluttering sensation in the chest, chest pain, fainting, or dizziness.
Arteries
3. Arteries: Blood vessels that transport blood away from the heart, typically oxygenated blood (except for the pulmonary arteries). They are typically thick and elastic to accommodate high pressure.
Blood
4. Blood: A fluid that circulates throughout the body, transporting oxygen, nutrients, hormones, and waste products. It consists of plasma and cellular components (erythrocytes, leukocytes, and thrombocytes).
Capillaries
5. Capillaries: The smallest blood vessels in the body, with walls only one cell thick, where gas, nutrient, and waste exchange occurs between the blood and body tissues.
Circulatory system
6. Circulatory system: The body system, composed of the heart, blood vessels (arteries, veins, and capillaries), and blood, responsible for internal transport of materials like oxygen and nutrients and the removal of waste products.
Diastole
7. Diastole: The relaxation phase of the cardiac cycle when the heart chambers (atria and ventricles) are filling with blood.
Endocardium
8. Endocardium: The innermost layer of tissue that lines the chambers and valves of the heart.
Erythrocytes
9. Erythrocytes: Red blood cells; the most common type of blood cell, rich in hemoglobin, responsible for delivering oxygen to body tissues.
Hemoglobin
10. Hemoglobin: An iron-containing protein found within erythrocytes (red blood cells) that binds to oxygen and is responsible for the blood's red color.
Left atrium
11. Left atrium: One of the two upper chambers of the heart; it receives oxygenated blood from the lungs via the pulmonary veins and pumps it into the left ventricle.
Left ventricle
12. Left ventricle: One of the two lower chambers of the heart; it pumps oxygenated blood through the aortic valve into the aorta and out to the rest of the body. It has the thickest muscle wall.
Leukocytes
13. Leukocytes: White blood cells; the cellular components of blood that play a vital role in the body's immune defense and fight infections.
Mitral valve
14. Mitral valve: Also known as the bicuspid valve, this heart valve is located between the left atrium and the left ventricle, preventing backflow of blood into the atrium.
Myocardium
15. Myocardium: The thick, muscular middle layer of the heart wall, responsible for the heart's contraction and pumping action.
Pericardium
16. Pericardium: A double-walled protective sac that encloses the heart and the great blood vessels, containing a lubricating fluid.
Plasma
17. Plasma: The clear, extracellular fluid component of blood, in which the blood cells are suspended.
Pulmonary valve
18. Pulmonary valve: A heart valve located between the right ventricle and the pulmonary artery (or pulmonary trunk) that prevents the backflow of deoxygenated blood into the ventricle.
Right atrium
19. Right atrium: One of the two upper chambers of the heart; it receives deoxygenated blood from the body via the venae cavae and pumps it into the right ventricle.
Right ventricle
20. Right ventricle: One of the two lower chambers of the heart; it pumps deoxygenated blood through the pulmonary valve into the pulmonary arteries, which lead to the lungs.
Septum
21. Septum: A muscular wall that divides the right and left sides of the heart, separating the atria and the ventricles.
Systole
22. Systole: The contraction phase of the cardiac cycle when the heart (ventricles) contracts and ejects blood to the lungs and body.
Thrombocytes
23. Thrombocytes: Platelets; small cellular components in the blood that are essential for blood clotting and stopping bleeding.
Tricuspid valve
24. Tricuspid valve: The right atrioventricular valve, located between the right atrium and the right ventricle, with three flaps (cusps) that ensure one-way blood flow.
Veins
25. Veins: Blood vessels that carry blood back to the heart, typically deoxygenated blood (except for the pulmonary veins). They contain valves to prevent the backflow of blood.