Cardiac System & Circulation Flashcards
4 components of blood
plasma, erythrocytes, leukocytes, platelets
aneurysm
a bulge that weakens the wall of the artery and could lead to rupture
arteries are high/low pressure blood carriers
high pressure carriers
arteries carry blood to/from the heart
from the heart
arteries have narrow/wide lumens
narrow lumens, to keep pressure high. has thicker walls in order for this to occur
atheromas
fatty deposits that develop and narrow the size of the lumen, and reduce elasticity of artery wall
atherosclerosis
the hardening and narrowing of arteries due to a buildup of plaque
damage to artery walls created by high blood pressure causes chronic inflammation, leading to accumulation of debris like lipids and cholesterol
atrioventricular node (AVN)
node that delays signal from the SAN to allow atria to contract before the ventricles and ensure they are at 70% capacity
autonomic control
means that there is no voluntary control over the heart by the brain, it only happens automatically
bachman’s bundle
group of nerves that bring the signal from the SAN to the left atrium from the right atrium
blood pathway through the heart
- Superior vena cava
- right atrium
- right ventricle
- pulmonary artery
- lungs
- pulmonary vein
- left atrium
- left ventricle
- aorta
- rest of body
bundles of his (or AV bundle)
nerves found in the septum, splits the signal to go to both ventricles
capilliaries
involved with material and oxygen transport, are very small and thin, walls are a single layer to help with diffusion
coronary arteries
network of arteries surrounding the heart that provide the heart muscle with nutrients and oxygen
when blocked, heart attack occurs as the heart muscle dies
coronary thrombosis
the buildup of atheromas, resulting in a clot/blockage in the coronary arteries, leading to acute myocardial infarction (heart attack)
diastole
relaxation of the heart
erythrocytes
red blood cells, responsible for transferring O2
features of cardiac muscle
mononucleated, myogenic, involuntary control, y-shaped cells, shorter and wider
fibrillation
erratic and irregular heartbeat
hemorrhagic stroke
stroke caused by the rupture of blood vessels, caused by high BP, blood thinners, anneurisms, trauma, and protein deposits
how does diastole occur?
once blood flows into the arteries from the systole, pressure in ventricles drop, closing the semilunar valves and making the “dub” sound
when pressure in ventricle drops below atrial pressure, AV valves open again and cycle repeats
how does systole occur?
blood moves freely from atria to the ventricles, then, when the ventricles reach 70% capacity, the SAN fires, contracting the atria. contraction of the atria causes the blood to be forced into the ventricles, maxing out their capacity.
after delay from the AVN, the ventricles are told to fire, and increased pressure causes closing of AV value, and opening of semilunar valves and blood moves into arteries, decreasing pressure in the ventricles
how is the first “lub” heart sound created?
when the ventricles contract, the increased pressure in the ventricles closes the AV valve, making the “lub” sound
intercolated disks
special junctions between cardiac cells that allow for fast electric transmission (action potential) and nutrient exchange (allows all heart cells to beat TOGETHER)
