Chapter 6: The Circulatory System Flashcards
Blood Vessel structure
walls are composed of endothelial tissue, smooth muscle, and connective tissue
lumen
space within blood vessel blood flows through
arteries
large, thick-walled blood vessels that propel O2 rich blood
aorta
largest artery; branches into smaller arteries (branches straight off the heart)
radial artery
artery located near the thumb side of wrist; most common site for obtaining a pulse rate
carotid artery
artery located near the side of the neck; the most accessible site to check for a pulse rate in an emergency
brachial artery
artery located in the antecubital space of the elbow; the most common place to obtain a blood pressure reading
femoral artery
artery located in the groin area; may be used for arterial punctures by specially trained personnel
pulmonary artery
only artery that does not carry oxygenated blood (carries blood from heart to lungs)
veins
thinner walls carry O2 poor blood, CO2, other waste products back to heart; have one way valves
capillaries
smallest vessel; contain arterial and venous blood
superior vena cava
vein that carries blood from the upper body to the heart
inferior vena cava
vein that carries blood from the lower body to the heart
great saphenous
principle vein in the leg and longest vein in the body
pulmonary vein
only vein carrying oxygenated blood (from lung to heart)
heart location
hollow, muscular organ located in thoracic cavity between lungs and to the left
heart layers (outer to inner)
epicardium, myocardium, and endocardium
heart chambers
right and left atrium (collect blood), right and left ventricles (pump blood)
right side of heart
pump for pulmonary circulation
left side of heart
pump for the systemic circulation
Blood pathway #1
superior and inferior vena cava bring O2 poor blood to R.A.
blood pathway #2
blood passes through the tricuspid valve to R.V.
Blood pathway #3
R.V. contracts and pumps blood through the pulmonary semilunar valve
Blood pathway #4
blood is transported by the pulmonary arteries to both lungs for oxygenation
blood pathway #5
oxygenated blood is brought back to the left atrium by the pulmonary veins
blood pathways #6
blood passed through bicuspid (mitral) valve into L.V.
blood pathway #7
blood leaves the L.V. through aortic semilunar valve into aorta
Heart disorders
angina pectoris, bacterial endocarditis, congestive heart failure, myocardial infarction, pericarditis, rheumatic heart disease
Cardiac Cycle
contraction (systolic) and relaxation (diastolic) of the cardiac muscle that occurs in one heartbeat
Cardiac Cycle Path
1.SA Node
2.AV Node
3.Bundle of His
4.R/L Bundle Branches
5.Purkinje Fibers
SA node
in upper right atrium, pacemaker of heart, initiates the heartbeat
AV node
in lower interatrial septum, receives the electrical impulse, both right and left atria contract, forcing blood into ventricles
purkinje fibers
covers ventricles, causes ventricular contraction
electrocardiogram
measures cardiac cycle with electrodes, P wave represents transmission of the SA node to atria, GRS complex and T wave represents activity of ventricles
heart rate/pulse rate
60-80 times per minute
arrhythmia
irregular heart rate
bradycardia
<60 bpm
tachycardia
> 100 bpm
blood pressure
pressure exerted by the blood on the walls of blood vessels during contraction and relaxation
Blood components
plasma, erythrocytes, leukocytes, platelets
plasma
55% of total blood volume; clear pale-yellow fluid that is 91% water
plasma contents
proteins, nutrients, mineral, gases, vitamins, hormones, waste products, 91% water; has Abs that react with Ags on RBCs
RBCs
contain hemoglobin for transporting O2 and CO2; contain surface Ags that make up ABO and Rh type
WBCs
provides immunity; 5 types
neutrophils
kill bacteria, respond to inflammation
lymphocytes
kill viruses; make antibodies
monocytes
digest foreign material
eosinophils
kills parasites, respond to allergies
basophils
release histamine
platelets
small irregular cell fragments that cause blood to clot
Coagulation Stage 1
blood vessels constrict (minimize blood loss), platelets become sticky; platelets clump to form a plug at the site of vascular damage
Coagulation Stage 2
coagulation cascade; series of proteins that get activated, form hairlike strands to fill in gaps between platelets to make a more secure clot
Coagulation Stage 3
clot retracts bringing the torn vessel edges closer together
Coagulation Stage 4
damage to vessel is repaired, clot gets dissolved
