Ch. 7.8 Circulatory System Key Terms
aortic valve
located between the left ventricle and the aorta, the largest artery in the body. 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.
circulatory system
also known as the cardiovascular system, is often referred to as the "transportation" system of the body. It consists of the heart, blood vessels, and blood.
left atrium
Receives oxygenated blood from the lungs.
pericardium
a double-layered membrane, or sac, that covers the outside of the heart.
septum
a muscular wall that separates the heart into a right side and a left side. It prevents blood from moving between the right and left sides of the heart.
arrhythmias
abnormal heart rhythms and can be mild to life threatening.
diastole
a brief period of rest, followed by a period of ventricular contraction, called systole.
left ventricle
Receives blood from the left atrium and pumps the blood into the aorta for transport to the body cells
plasma
approximately 90 percent water, with many dissolved, or suspended, substances.
systole
a period of ventricular contraction
arteries
carry blood away from the heart.
endocardium
a smooth layer of cells that lines the inside of the heart and is continuous with the inside of blood vessels. It allows for the smooth flow of blood.
leukocytes
are not as numerous as are erythrocytes. They are formed in the bone marrow and lymph tissue and usually live about 3–9 days.
pulmonary valve
is located between the right ventricle and the pulmonary artery, a blood vessel that carries blood to the lungs. It closes when the right ventricle has finished contracting, preventing blood from flowing back into the right ventricle.
thrombocytes
v also called platelets, are usually described as fragments or pieces of cells because they lack nuclei and vary in shape and size
blood
made of the fluid called plasma and formed or solid elements called blood cells
erythrocytes
Are produced in the red bone marrow at a rate of about one million per minute. They live approximately 120 days before being broken down by the liver and spleen.
mitral valve
is located between the left atrium and left ventricle. It closes when the left ventricle is contracting, allowing blood to flow into the aorta (for transport to the body) and preventing blood from flowing back into the left atrium
right atrium
receives blood as it returns from the body cells.
tricuspid valve
is located between the right atrium and the right ventricle. It closes when the right ventricle contracts, allowing blood to flow to the lungs and preventing blood from flowing back into the right atrium.
capillaries
connect arterioles with venules, the smallest veins. Capillaries are located in close proximity to almost every cell in the body. They have thin walls that contain only one layer of cells.
hemoglobin
a complex protein composed of the protein molecule called globin and the iron compound called heme. Hemoglobin carries both oxygen and carbon dioxide.
myocardium
the muscular middle layer (of the heart).
right ventricle
Receives blood from the right atrium and pumps the blood into the pulmonary artery, which carries the blood to the lungs for oxygen.
veins
blood vessels that carry blood back to the heart.