Ch. 7.8 Circulatory System Key Terms
Located between the left ventricle and the aorta; it closes when the left ventricle is finished contracting, allowing blood to flow into the aorta and preventing blood from flowing back into the left ventricle.
aortic valve
Also known as the cardiovascular system; referred to as the "transportation" system of the body. It consists of the heart, blood vessels, and blood.
circulatory system
Receives oxygenated blood from the lungs.
left atrium
A double-layered membrane, or sac, that covers the outside of the heart.
plasma: The fluid that blood is made of; it is approximately 90 percent water with many dissolved substances (such as proteins, nutrients, gases, and hormones).
pericardium
A period of ventricular contraction in the cardiac (heartbeat) cycle.
systole
Abnormal heart rhythms.
arrhythmias
A brief period of rest in the cardiac (heartbeat) cycle.
diastole
Receives blood from the left atrium and pumps the blood into the aorta for transport to the body cells.
left ventricle
Located between the right ventricle and the pulmonary artery; it closes when the right ventricle has finished contracting, preventing blood from flowing back into the right ventricle.
pulmonary valve
Also called platelets; fragments or pieces of cells that are important for the clotting process.
thrombocytes
Blood vessels that carry blood away from the heart.
arteries
A smooth layer of cells that lines the inside of the heart and is continuous with the inside of blood vessels.
endocardium
White blood cells; their main function is to fight infection.
leukocytes
Receives blood as it returns from the body cells.
right atrium:
Located between the right atrium and the right ventricle; it closes when the right ventricle contracts, preventing blood from flowing back into the right atrium.
tricuspid valve
Often called a tissue because it contains many kinds of cells. It transports oxygen, carbon dioxide, nutrients, metabolic and waste products, heat, and hormones.
blood
Red blood cells; they contain hemoglobin, which carries oxygen and carbon dioxide.
erythrocytes
Located between the left atrium and left ventricle; it closes when the left ventricle is contracting, preventing blood from flowing back into the left atrium.
mitral valve
Receives blood from the right atrium and pumps the blood into the pulmonary artery.
right ventricle
Blood vessels that carry blood back to the heart.
veins
Connect arterioles with venules; their thin walls allow oxygen and nutrients to pass through to the cells and allow carbon dioxide and metabolic products to enter the capillaries.
capillaries
A complex protein composed of the protein molecule called globin and the iron compound called heme; it carries both oxygen and carbon dioxide.
hemoglobin
The muscular middle layer of the heart; the thickest layer.
myocardium
A muscular wall that separates the heart into a right side and a left side.
septum
veins
Blood vessels that carry blood back to the heart.