Studied by 10 people
The heart
the organ responsible for pumping blood through the vessels of the cardiovascular system.
pericardial cavity
contains the heart
Base
The superior end of the heart, to which the "great veins and arteries," are attached
Apex
The inferior tip of the heart
Atrium
small chamber in the human heart that receives blood from the veins
Ventricule
A larger chamber of the heart that pumps blood out to the lungs and body
Pulmonary
pertaining to the lungs
pulmonary circuit
Blood vessels that carry blood from the heart, to the lungs, then back to the heart
Systematic circuit
Blood vessels that carry blood from the heart to all other parts of the body and then back to the heart.
Pericardium
A set of membranes that cover the heart
Fibrous pericardium
outermost layer of pericardium, anchors the heart in place
Parietal Pericardium
outer layer of the pericardium, lines the pericardial cavity
Visceral Pericardium
innermost layer, covers the heart
Outermost layer of the heart
Pericardial Fluid
fills the space between the parietal and visceral layers, lubricates the heart, and reduces friction as it pumps.
3 layers of the heart
epicardium, myocardium, endocardium
Epicardium
outermost layer of the heart, additional layer of protection from trauma or friction for the heart under the pericardium.
Myocardium
thickest layer of tissue that makes up the heart,made of cardiac muscle, blood vessels, and nerves.
Endocardium
a thin layer of epithelial tissue that lines the chambers of the heart.
Septa
Walls of tissue separating the four chambers of the heart
interatrial septum
thin layer of myocardium that separates the two atrias
interventricular septum
a thick layer of myocardium that separates the two ventricles
atrioventricular septum
layer of tissue between the atria and ventricles
Orfice
an opening
Valves
prevent back flow of blood
tricuspid valve
prevents blood from flowing back into the right atrium from the right ventricle
bicuspid valve/ mitral valve
prevents blood from flowing back into the left atrium from the left ventricle
chordae tendineae
Connective tissue fibers that help to prevent the valves from being forced to open backwards
pulmonary semilunar valve
prevent blood from flowing back into the right ventricle
aortic semilunar valve
of prevents blood from flowing back into the left ventricle
Contractile cells
contracts and generates the force to pump blood
Conducting cells/ "autorhythmic cells"
control electrical activity of the heart, and set the heart beat
hypertrophic cardiomyopathy
A condition in which the heart muscle becomes abnormally thick.
Shape of heart
cone-shaped, similar to a pinecone
Size of heart
size of fist
Left ventricle
pumps blood into the systemic circuit via the opening to the aorta.
Right Ventricle
pumps blood into the pulmonary circuit via the opening to the pulmonary trunk.
Left Atrium
flows into the left ventricle through the bicuspid orifice
Right Atrium
flows into the right ventricle through the tricuspid orifice.
Intercalated discs
Link cardiac muscle cells together
Desmosomes
Help link the cells together with strength
functional syncytium
describes how branches and gap junctions link the entire myocardium into a single functional unit
Cardiac muscle cells structure
Short, small in diameter, and branched
4 Great vessels
Superior + inferior vena cava
aorta
pulmonary trunk
Pulmonary veins
4 Chambers
Left atrium
Right atrium
Left ventricle
Right ventricle
4 Valves
Tricuspid
Bicuspid (mitral)
Pulmonary semilunar
Aortic Semilunar
Flow of Blood
Superior and inferior vena cavae - right atrium - tricuspid valve - right ventricle - pulmonary semilunar valve - pulmonary artery - pulmonary veins - left atrium - bicuspid valve - left ventricle - aortic semilunar valve - aorta
Left side of heart (Systemic circuit)
pumps blood to the body
Right side of heart (Pulmonary circuit)
Pumps blood to and through lungs
serous membrane
Thin, shiny lining covering the heart. Also lines the inside of the heart
5 layers of the heart + membrane
Fibrous pericardium
Parietal pericardium
visceral pericardium/ epicardium
myocardium
endocardium
Functional syncytium
multiple cells coming together and acting as one unit
Cardiac cycle
period from the beginning of one heartbeat to the beginning of the next
Systole
Contraction of the heart
diastole
Relaxation of the heart
Interatrial septum
Thin layer of myocardium
Interventricular septum
thick layer of myocardium
Intrinsic and extrinsic control mechanisms
Controls the rate at which the heart beats
contractile cells
Contract and generate the force to pump blood
Where are contractile cells located
myocardium
Conducting cells
control electrical activity of the heart and set the heart beat.
functional syncytium
branches and gap junctions link the entire myocardium into a single functional unit.
Which node depolarizes at the fastest rate?
The Sinoatrial (SA) Node
Atrioventricular node
picks up electrical impulses and spreads it across the atria and carries it to the ventricles at a slower speed
Purkinje Fibers
picks up electrical activity and rapidly spreads a wave of depolarization across the myocardium of the ventricles.
Cardiac cycle
the period from the beginning of one heartbeat to the beginning of the next one.
Atrial systole
contraction of the atria
End-diastolic volume (EDV)
the volume of blood in the ventricles is maximal after atrial systole
End- systolic volume( ESV)
The volume of blood in the heart at the end of ventricular systole
Stroke Volume
the quantity of blood ejected by the ventricles
Ejection Fraction
Percentage of blood pumped out
Isovolumetric contraction
Volume of fluid remains constant while all ventricles are contracting
Isovolumetric relaxation
All four valves are closed simultaneously
Cardiac Output
The volume of blood pumped by each ventricle in a minute
Contractility
The force exerted by the myocardium
Positive inotropic effect
Any factor that increases contracitility
Negative inotropic effect
Any factor that decreases contractiility
Afterload
the amount of force the ventricles must produce to eject blood through the semilunar valves
Filling time
The duration of ventricular diastole
Venous return
the rate of flow back to the heart from the body
Stroke Volume equation
SV= EDV- ESV
Cardiac Output equation
CO(ml/min)= HR (beat/min) x SV (ml/beat)
intercalated disk
Links cardiac muscle cells
Ejection fraction equation
SV/EDV x100
Cardioacceleratory center
stimulates sympaatheric neurons to send signals to the heart
Vagus nerves
release acetylcholine (ACh)
P wave
Depolarization of atria
QRS complex
Contraction of ventricles
T wave
Repolarization of the ventricles
Depolarization
Contracting
Repolarization
Relaxed
Note 
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