Pulmonary circuit
Carries blood to and from gas exchange gas exchange surfaces of lungs
Systemic circuit
Carries blood to and from the body
Blood alternates between pulmonary circuit and systemic circuit
How many types of blood vessels
3 arteries, veins, capillaries
Arteries
Carry blood away from the heart
Veins
Carry blood to the heart
Capillaries
(Single layer wall)
�Networks between arteries and veins
�exchange vessels-exchange materials between blood and tissue
�materials include dissolved gases nutrients waste products
How many chambers in the heart
Four
Right atrium
Collects blood from systemic circuit
Right ventricle
Pumps blood to pulmonary circuit
Left atrium
Collects blood from pulmonary circuit
Left ventricle
Pumps blood to systemic circuit
Anatomy of the heart
�great veins and arteries at the base
�pointed tip is apex
�surrounded by pericardial sac
�sits between to plural cavities in the mediastinum
The heart is actually(1,2,3) pumps?
Two pumps
Which chamber receives blood from the superior and inferior vena cavae?
Right atrium
Which chamber receives blood from the pulmonary veins?
Left atrium
Which heart chamber pumps unoxygenated blood out the pulmonary trunk?
Right ventricle
Which chamber pumps oxygenated blood out of the aorta to the systemic circuit?
Left ventricle
The epicardium is also known as the
Visceral pericardium
The papillary muscles function to
Prevent the AV valves from reversing into the atria
The pulmonary veins carry ___blood to the ____atrium
Oxygenated ; left
The adult heart is roughly the size of
A mans clenched fist
Tetanic muscle contractions don't occur in a normal cardiac muscle because
The refractory period lasts until muscle relaxes
Intercalated discs serve to transfer____from cell to cell
�electrical signals
�action potentials
�the force contraction
�ionic currents
The cusps of atrioventricular valves attach directly to
Chordae tendineae
The right ventricle pumps blood to the
Right and left lungs
Coronary veins empty into the
Right atrium
The ____ delivers blood to the myocardium
Coronary arteries
The ____ valve prevents backward flow into the left atrium
Bicuspid
The foramen ovale in the fetal heart is located in the
Interatrial septum
The circumflex branch and the anterior inter ventricular artery are branches of the
Left coronary artery
The___ is a remnant of an important fetal blood vessel that once linked the pulmonary and systemic circuits
Ligamentum arteriosum
Heart rate is controlled by
Both right vagus and sympathetic nerves
The plateau phase of the ventricular action potential corresponds to the __ phase of the electrocardiogram
ST segment
Which wave is the largest in the EKG
R
The normal pacemaker of heart is located in
The sinotrial node
If the connection between the SA node and AV node became blocked
The ventricles will beat more slowly
The T wave on an ECG tracing represents
Ventricle repolarization
____is to slow the heart rate as___is to fast the heart rate
Bradycardia ; tachycardia
The property of heart muscle contraction in the absence of neural or hormonal stimulation is called
Automaticity
The volume of blood remaining in the ventricle as diastole begins is called
End systolic volume
The wall of the left ventricle is thicker than the right; the left ventricle pumps more blood than the right. Are these two statements true
The first is true
During ventricle systole the blood pressure___and ventricle volume____
Increases; decreases
The first heart sound "lub
Associated with closing of the mitral valve
A heart murmur might be caused by
�swirling of blood in ventricle
�pulmonic valve insufficiency
�mitral valve insufficiency
�aortic valve insufficiency
At a heart rate of 60 beats/minute a cardiac cycle lasts
1 second
The contraction phase of the cardiac cycle is called
Systole
As the heart rate slows____gets longer
Diastole
Which of these is not needed to determine cardiac output
Blood pressure
The volume of blood ejected from each ventricle during a contraction is called the
Stroke volume
The heart is innervated by___nerves
Both parasympathetic and sympathetic
Drugs that block the beta one adrenergic receptors will
Decrease heart rate
___is when the heart can't maintain adequate cardiac output
Heart failure
The amount of blood returning to the heart is
Venous return
The qrs complex represents
Ventricular depolarization
The p wave represents
Atrial depolarization
The P wave represents
Atrial depolarization
The T wave represents
Ventricular depolarization
The contractile cells of the myocardium reach threshold because of an influx of
Cations
The conduction delay that occurs at the AV node allows
The atria to contract before the ventricles begin to contract
QRS complex
Represents the depolarization of ventricles
Contraction of the chambers of the heart is
Systole
Relaxation of the chambers of the heart is
Diastole
The first sound lubb marks the point when
The atrioventricular valves close
There are ___ heart sounds
4
The stroke volume of the heart is approximately
80ml
Stroke volume
The amount of blood ejected from each ventricle during ventricular systole