Cardiovascular System Flashcards
it transports and circulates materials throughout the body and has extensive connection with organ systems that exchange materials with the environment, linking the various tissues of the body
cardiovascular or circulatory system
pumps blood through a network of blood vessels extending throughout the body
heart
tubular structures carrying blood to the tissues and organs
blood vessels
delivers necessary substances and picks up waste products at the body tissues
blood
it is a pump that keeps the blood moving through the blood vessels
heart
the heart is located in the __________, a midline portion of the thoracic cavity that also contains the trachea, the esophagus, the thymus, and associated structures
mediastinum
the adult heart is shaped like a __________ __________ and is approximately the size of a closed fist, with an average mass of 250 grams in females and 300 grams in males
blunt cone
blunt rounded point, directed to the left with with approximately 2/3 of the heart’s mass lies to the left of the midline of the sternum
apex
the apex is located deep to the __________ __________ __________, approximately 7-9 cm to the left of the sternum and medial to the midclavicular line
fifth intercostal space
larger flat part at the opposite end of the apex, located deep to the sternum and extends to the second intercostal space
base
the base is located deep to the sternum and extends to the __________ __________ ___________
second intercostal space
contraction of the heart __________ __________ ________, which is responsible for moving blood through the blood vessels
functions
generating blood pressure
the heart separate the pulmonary and systemic circulations and ensure better oxygenation of the blood flowing to the tissues
functions
routing blood
the valves of the heart ensure a one way blood flow of blood through the heart and blood vessels
functions
ensuring one way blood flow
the rate and force of heart contractions change to meet the metabolic needs of the tissues, which vary depending on such conditions as rest, exercise, and changes in body position
functions
regulating blood supply
a double sac membrane that encloses the heart for protection
pericardium or pericardial sac
this outer layer is a tough fibrous connective tissue layer that prevents over distention of the heart and anchors it within the mediastinum
fibrous pericardium
the inner layer of simple squamous epithelium
serous pericardium
the two parts of the serous pericardium
- parietal pericardium
- visceral pericardium
the part that lines the fibrous pericardium
parietal pericardium
also called as the epicardium, the part covering the heart surface
visceral pericardium
the space between the visceral and parietal pericardia filled with serous pericardial fluid, helping reduce friction as the heart moves within the sac
pericardial cavity
swelling of pericardium
pericarditis
heart walls (from superficial to deep)
epicardium
myocardium
endocardium
the visceral pericardium, it is the superficial layers of thin serous membrane that constitutes the smooth outer surface of the heart
epicardium
thick middle layer of the heart and is composed of cardiac muscle cells and is responsible for the heart’s ability to contract
myocardium
the smooth inner surface of the heart chambers, consists of simple squamous epithelium allowing blood to move easily through the heart and is also covers the surfaces of the heart valves
endocardium
inflammation of the heart muscles
myocarditis
a life-threatening inflammation of the inner lining of the heart’s chambers and valves
caused by infection
endocarditis
the __________ are 2 upper chambers in the heart
they are the primer pumps that send blood to the ventricles
atria
receives deoxygenated blood from the body and pumps blood to the right ventricle
right atrium
receives oxygenated blood from the lings and pumps blood to the left ventricle
left atrium
wall of tissue that separates the right and left atria from each other
interatrial septum
they are 2 lower chambers in the heart
they pump the blood to the lungs or the rest of the body
ventricles
receives deoxygenated blood from the right atrium and pumps blood to the lungs for gas exchange
right ventricle
receives oxygenated blood from the left atrium and pumps blood to the body
left ventricle
a thick muscular wall that separates the left and right ventricles
interventricular septum
located between the atria and the ventricles
these keep the blood from moving back into an atrium when a ventricle contracts
atrioventricular valves
located between the right atrium and right ventricle which prevents back flow of blood into the right atrium
tricuspid valve
located between the left atrium and ventricles which prevents back flow of blood into the left atrium
bicuspid / mitral valve
heart strings, strong connective tissue attaching the papillary muscles (cone shaped muscular pillars) of the ventricles to the cusps of the atrioventricular valves
chordae tendineae
located between the ventricles and the major blood vessels leaving the heart
these prevent back flow in the ventricles from the arteries leaving the heart
semilunar valves
located between the right ventricle and the pulmonary artery which prevents back flow of blood into the right ventricle
pulmonic valve
located between the left ventricle and the aorta which prevents back flow of blood into the left ventricle
aortic valve
known as the natural pacemaker of the heart
this region of specialized cardiac muscle cells sets the tempo of the beat with electrical signals
sinoatrial (SA) node
each time the cells of the pacemaker fire, they stimulate the cardiac cells of the __________ to contract
atria
a cluster of cells situated in the center of the heart between the atria and ventricles that receives the electrical signals from the SA node
atrioventricular (AV) node
the __________ __________ then sends the electrical stimulation to the ventricle walls for ventricular contraction
atrioventricular (AV) node
the conducting bundle of the heart rising from the atrioventricular node
this bundle passes through a small opening in the fibrous skeleton to reach the interventricular septum, where it divides to form the right and left bundle branches
bundle of His / the atrioventricular bundle
the inferior terminal branches of the bundle and are large diameter cardiac muscle fibers
they have fewer myofibrils than most cardiac cells and do not contract forcefully
purkinjie fibers
the heart is __________ because it stimulates itself to contract at regular intervals
autorhythmic
it records the electrical signals of the heart
electrocardiogram
a type of arrhythmia, or irregular heartbeat, that affects your heart’s ventricles
defibrillation can restore your heart to its normal rhythm
ventricular fibrillation
a single beat of the heart that consists of the events that occur with each contraction and relaxation of the heart muscle
cardiac cycle
it refers to the repetitive pumping process that begins with the onset of cardiac muscle contraction and ends with the beginning of the next contraction
cardiac cycle
__________ means to contract
__________ means to dilate
systole
diastole
events in the cardiac cycle
atrial systole
ventricular systole
ventricular diastole
the atria contract, increasing atrial pressure and completing ventricular filling while the ventricles are relaxed and remain in diastole
active ventricular filling
ventricular contraction begins with the initial rise in intraventricular pressure closes the AV valves, preventing backflow of blood into the atria
the semilunar valves were closed in the previous ventricular diastole and remain closed during this period
atrial diastole begins, allowing atrial filling
period of isovolumetric contraction
continued ventricular contraction causes a greater increase in ventricular pressure, which pushed the blood out of the ventricles causing the semilunar valves to open
the atria remains in diastole, still relaxed and fills with blood
period of ejection
the ventricles begin to relax in diastole, blood flowing back from the aorta and pulmonary trunk toward the relaxing ventricles causes the semilunar valves to close
the AV valves remain closed
period of isovolumetric relaxation
ventricular relaxation continue, the AV valves open, and blood passively flow from the atria into the relaxing ventricles
the semilunar valves are closed
passive ventricular filling
low pitched sound “lubb” occurs at the beginning of ventricular systole and is caused by the vibration of the atrioventricular valves and surrounding fluid as the valves close
first heart sound
higher pitched sound “dupp” occurs at the beginning of ventricular diastole and results from closure of the aortic and pulmonary semilunar valves
second heart sound
the cardiovascular system comprises of the heart and two sets of blood vessels:
pulmonary vessels and systemic vessels
transport blood from the right ventricle, through the lungs, and back to the left atrium
pulmonary vessels
transport blood through all parts of the body from the left ventricle back to the right atrium
whereas the heart provides the major force that causes blood to circulate
systemic vessels
blood vessels carry blood from the heart to almost all the body tissues and back to the heart
functions
carries blood
nutrients and oxygen diffuse from blood vessels to cells in all areas of the body
waste products and carbon dioxide diffuse from the cells, where they are produced, to blood vessels
functions
exchanges nutrients, waste products, and gases with tissues
hormones, components of the immune system, molecules required for coagulation, enzymes, nutrients, gases, waste products, and other substances are transported in the blood to all areas of the body
functions
transport substances
the circulatory system and the heart work together to maintain blood pressure within a normal range of values
functions
helps regulate blood pressure
the circulatory system directs blood to tissues when increased blood flow is required to maintain homeostasis
functions
directs blood flow to tissues
innermost layer which consists of endothelium, a delicate connective tissue, and a fenestrated layer of elastic fibers
tunics intima
middle layer which consists of smooth muscle cells arranged circularly around the blood vessel
tunica media
the amount of blood flowing through a blood vessel can be regulated by contraction or relaxation of the smooth muscle in the __________ __________
tunica media
outermost layer which is composed of connective tissue, which varies from dense connective tissue near the tunica media to loose connective tissue that merges with the connective tissue surrounding the blood vessels
tunica externa / tunica adventitia
the narrowing of blood vessels that occurs when smooth muscle in the blood vessel walls contract
vasoconstriction
the widening of blood vessels when the smooth muscles of the blood vessels relax
vasodilation
are large vessels that conduct oxygenated blood away from the heart
arteries
are smaller vessels that branch out from the arteries and carries oxygenated blood to the capillaries
arterioles
delivers oxygenated blood to head and neck
common carotid artery
carries oxygenated blood away from the heart, largest artery in the body
aorta
delivers oxygenated blood to lower extremities, digestive tract, and pelvic organs
abdominal aorta
supply oxygenated blood to various structures between the aortic arch and the diaphragm
thoracic aorta
carry deoxygenated blood from the heart to the lungs
pulmonary arteries
deliver oxygenated blood to the heart muscles
coronary arteries
delivers oxygenated blood to the arm
brachial artery, axillary artery, subclavian artery
delivers oxygenated blood to the kidney
renal artery
delivers oxygenated blood to thigh and inner knee
femoral artery
large vessels that carry deoxygenated blood back to the heart
have diameters greater than 2 mm contain valves
veins
smallest vessels collecting deoxygenated blood from the capillaries
venules
receives deoxygenated blood draining from head and neck
jugular vein
carries deoxygenated blood to the heart, largest veins in the body
vena cava
receives deoxygenated blood from all areas above the diaphragm
superior vena cava
receives deoxygenated blood from all regions below the diaphragm
inferior vena cava
delivers oxygenated blood from the lungs to the heart
pulmonary veins
carry deoxygenated blood from the heart mucles
cardiac veins
carry deoxygenated blood from the upper limbs
brachial vein, axillary vein, subclavian vein
carries deoxygenated blood from the gastrointestinal tract, gallbladder, pancreas and spleen to the liver
hepatic portal vein
receives deoxygenated blood from thigh and inner knee
femoral vein
the tiniest blood vessels where the arterioles diverge
capillaries
water and dissolved substances like oxygen, carbon dioxide and glucose diffuse between each capillary and the interstitial fluid
capillary
fluid that surrounds the body’s cells
this fluid exchanges materials with the tissue cells
interstitial fluid
carries blood to the lungs for gas exchange and return it to the heart
pulmonary circulation
it is the system of blood vessels that carries blood from the right ventricle of the heart to the lungs and back to the left atrium of the heart
pulmonary circulation
the heart pumps blood from the right ventricle into a short vessel called the ___________ __________
it then branches into the right and left pulmonary arteries, one transporting blood to each lung
pulmonary trunk
a pressure wave that travels rapidly along the arteries as blood is ejected from the left ventricle into the aorta
pulse
what is the clinical importance of the pulse
determine the heart rate and rhythm
blood flows in long, smooth walled tubes as if it were composed of large number of concentric layers
laminar flow
is caused by numerous small currents flowing cross or obliquely to the long axis of the vessel, resulting in flowing whorls and eddy currents
turbulent flow
is a measure of a liquid’s resistant to flow
viscosity
as the viscosity of liquid increases, the pressure required to force it to flow also __________
increases
it is the tendency for blood vessel volume to increase as blood pressure increases
the more easily the vessel wall stretches, the greater is its compliance
vascular compliance
it is a measure of the force of blood exerts against blood vessel walls
blood pressure (BP)
pressure in your arteries when your heart beats
systolic
pressure in your arteries when your heart rest between beats
diastolic