Cardiovascular system Flashcards
What major organs compromise the cardiovascular system?
Heart, Blood Vessels (Arteries, Capillaries, Veins)
What are the functions of the cardiovascular system?
transports nutrients, wastes, water and hormones and helps regulate body temp.
What are the 3 tissue layers in the heart wall (outermost to inner)?
Epicardium, Myocardium, and Endocardium
What is the Epicardium made up of?
connective and epithelial tissue
What is the Myocardium made up of?
composed of cardiac muscle that pumps blood out of the heart
What is the Endocardium made up of?
connective and epithelial tissue
What is the pericardium?
A fibrous sac that encloses the heart
What are the two layers of the pericardium?
Visceral pericardium (Innermost layer) Parietal pericardium (Outside)
What are the functions of the A-V valves? What are they called?
ensure one way flow of blood from atria to ventrilce
- tricuspid and bicuspid valve
What is another name for the bicuspid valve?
Mitral valve
What are the cusps of the A-V valves connected to?
chordae tendinae
What are the semilunar valves?
Aortic valve and pulmonary valve
What does the aortic valve do?
opens to allow blood to leave heart into the body
What does the pulmonary valve do?
opens to allow blood to leave heart into the lungs
What are characteristics of the semilunar valves?
3 cusps and no chordae tendinae
What is the path of blood flow?
Right atrium - tricuspid valve-right ventricle-pulmonary valve- pulmonary trunk-pulmonary arteries- into lungs- pulmonary veins-left atrium- bicuspid valve-left ventricle- aortic valve- aorta- body
What are the 5 types of blood vessels?
arteries, arterioles, capillaries, venules, veins
What are the characteristics of arteries?
Strong, elastic
High pressure
carries blood away from heart
When arteries become smaller and divide, what forms?
arterioles
What are the 3 layers of an artery wall? What are the made of?
Tunica interna(Endothelium) Tunica Media(Smooth muscle) Tunica Externa(Connective)
What are the characteristics of capillaries?
Smallest vessels
Substances exchanged with tissue cells
What areas have more capillaries?
areas with great metabolic activity
What are the characteristics of veins and venules?
venules leading from capillaries merge to form veins
Same 3 layers as arteries
Have flap like valves that prevent backflow
thinner and less muscular
What does diastole mean?
relaxed
What does systole mean?
Contracted
What causes the “lub dub” sound?
lub: AV valves closing
dub: semilunar valves closing
What causes heart murmurs?
back flow through valve heart
What is the function of the SA node?
hearts pacemaker, stimulates atria to contract
What is the function of the AV node?
causes ventricles to contract after stimulated by SA node
How does the parasympathetic and sympathetic systems regulate the heart beats?
sympathetic- increases
parasympathetic- slows
What is the electrocardiogram?
a recording of electrical changes that occur during ther cardiac cycle
What happens during the P wave?
contraction of atria
What happens during the QRS complex?
contraction of ventricles, hides relaxation of atria
What happens during the T wave
ventricular relaxation
What is arrhythmia?
change from the normal sequence of electrical impulses
What is blood pressure?
The force of blood against the inner walls of blood vessels
When is arterial pressure the highest? The lowest?
highest- during ventricular contraction
lowest- ventricles relaxing
What is the way to find normal blood pressure?
systolic/ diastolic
What is the average systolic? (pressure in blood vessels when heart beats)
100-140
What is the average diastolic? (pressure in blood vessels between resting beats)
60-90
What is the normal heart rate?
60-100 BPM
