Ch. 5 Cardiovascular System Flashcards
heart
muscular organ between lungs
pericardium
double walled membranous sac enclosing heart
epicardium
external layer of heart/inner layer of pericardium
myocardium
middle and thickest layer of heart
endocardium
inner lining of heart
atria
2 receiving chambers
ventricle
2 pumping chambers
tricuspid valve
controls opening between right atrium and right ventricle
pulmonary semilunar valve
between right ventricle and pulmonary artery
mitral valve
between left ventricle and left atrium
aortic semilunar valve
between left ventricle and aorta
sinoatrial node (SA)
establishes basic rythm and rate. starts each wave of contractions. located near entrance of superior vena cava
atrioventricular node (AV)
gets impulse from SA and transmits it to Bundle of His
Bundle of His
group of fibers. carry impulse to ensure sequence of heart contractions
Purkinje fibers
within walls of ventricles. relay impulses to cells of ventricle to contract. forces blood out of heart
P wave
due to stimulation of atria
T wave
recovery of ventricles
QRS wave
stimulation of ventricles. atria relaxes as ventricle constrict
pulmonary circulation
blood flow between heart and lungs
systemic circulation
blood flow to all of body except lungs
arteries
carry blood away from heart. elastic and muscular to expand and contract
aorta
largest artery in body
carotid
carry blood to head. divides into internal carotid
arterioles
smaller branches of arteries that carry blood to capillaries
veins
low pressure collecting system to return blood to heart. thinner and less elastic. valves to prevent backflow
venules
smallest veins that connect veins to capillaries
vena cavae
2 largest veins. superior and inferior
capillaries
one cell thick. slow flow of blood to allow for exchange. 90% of fluid leaves opposite end of capillary bed through venules
pulse
rhythmic pressure against walls of an artery caused by heart contractions
blood pressure
measurement of amount of systolic and diastolic pressure
systolic pressure
pressure against artery wall while ventricles contract
diastolic pressure
pressure against artery wall while ventricles relax
plasma
fluid containing nutrients, hormones, and waste products. 91% water, 9% proteins
prothrombin and fibrinogen
clotting proteins found in plasma
serum
plasma fluid after blood cells and proteins have been removed
erythrocytes
RBCs. produced in red bone marrow. transports oxygen using hemoglobin
leukocytes
WBCs. immune cells
neutrophils
most common WBC. major role in immune defense
basophils
least common WBC. responsible for symptoms of allergies
eosinophils
WBC.destroy parasitic organisms. major role in allergic response
lymphocytes
WBC. identify foreign substances and germs to produce antibodies
monocytes
WBC. provide immune defense against infection
thrombocytes
platelets. smallest elements of blood. creates clot by becoming sticky
blood types
classified according to presence or absence of certain antigens. A, B, AB (presence of AB antigens) and O (both antigens are present)
RH Factor
presence/absence of RH antigen. 85% positive, 15% negative in US
blood gases
gases normally dissolved in liquid portion of blood. major are oxygen, carbon dioxide, and nitrogen
congenital heart defects
structural abnormalities caused by failure to develop before birth
coronary artery disease
atherosclerosis of coronary arteries. reduces supply to heart muscle
infarction
sudden insufficiency of blood
aneurysm
localized weak spot or balloon-like enlargement in wall of artery
thrombosis
abnormal clot
embolism
sudden blockage of blood vessel. can be from air or fat.
