Ch 8 The Circulatory System Flashcards
What does the circulatory system include?
the heart, arteries, arterioles, capillaries, venules and veins
Is the circulatory system entirely closed?
yes
What are the two circuits in the body?
systemic circulation and pulmonary circulation
Which circuit travels throughout the body?
the systemic circulation
Which circuit travels only between the heart and lungs?
the pulmonary circulation
The process of blood cell formation
hematopoiesis
The blood components and the organs involved in their development and production
the hematopoietic system
The primary site of hematopoietic cell production
the bone marrow
Secondary hematopoietic organs
the lymphoid tissues, consisting of the thymus, lymph nodes, and spleen
The ______ is involved with the filtering and breakdown of RBC’s, assists with the production of lymphocytes, and has an important role in providing homeostasis and infection control.
spleen
What two types of hematopoietic tissue are found in the body?
myeloid and lyphoid
What tissue is mainly found in the bone marrow and produces RBC’s, WBC’s, and blood platelets?
myeloid tissue
What tissue is found in the lymph nodes, spleen, and thymus and is the home to lymphocytes and other cells derived from them, such as plasma cells?
lymphoid tissue
What do plasma cells do?
produce antibodies to destroy antigens or antigen-containing particles
Name the five functions of the blood
respiratory, nutritional, excretory, regulatory and defensive
What is blood primarily composed of?
plasma (55%) and formed cellular fragments (45%)
The liquid portion of the blood in which the formed elements of blood are suspended
plasma
What comprises the major portion of the whole blood?
plasma
The formed elements are a mixture of ____, _____, and ______.
RBC’s, WBC’s, and platelets
What is plasma composed of?
water, proteins (albumins, globulins, fibrinogen), gases (oxygen, carbon dioxide, nitrogen), electrolytes, nutrients, vitamins, hormones, and wastes
Regulate oncotic pressure, and thereby control the movement of water into and out of the circulation
albumins
Important for blood clotting and makes up about 4% of the plasma proteins
fibrinogen
Antibodies made by the liver that make up around 36% of the plasma proteins
globulins
These are produced in the lymphatic tissue and they include proteins that act as antibodies in the immune system
gamma globulins
What carries oxygen to the tissues?
RBC’s
What gives RBC’s their red color?
hemoglobin
How many molecules of oxygen is each hemoglobin capable of binding to?
up to four
The ongoing process by which RBC’s are made
erythropoiesis
A hormone produced mainly by the kidneys that stimulates the production of RBC’s by stem cells within the bone marrow.
erythropoietin
The part of the hemoglobin that is not recycled is converted to
bilirubin
WBCs are derived from
stem cells
Functions of WBCs include
phagocytosis, production of antibodies, secretion of heparin and histamine, and secretion of other chemokines
Most WBCs are motile and leave the blood vessels by a process known as
diapedesis
The three types of granulocytes are
neutrophils, eosinophils and basophils
The two types of agranulocytes are
monocytes and lymphocytes
____ are normally the most common type of granulocyte in the blood, widely dispersed in the body, are highly specialized for finding and destroying bacteria, a primary defense against bacterial infection, and are also a major component of the inflammatory response.
neutrophils
____ release substances that damage or kill parasitic invaders, have a major role in mediating the allergic response, release chemotactic factors, which are substances that cause cells to migrate into an area.
eosinophils
The least common of all granulocytes that play a role in both allergic and inflammatory reactions.
basophils
____ dilates blood vessels, speeds blood flow to injured tissue, and makes blood vessels more permeable so that neutrophils, clotting proteins, and other blood components can enter connective tissues more quickly.
histamine
When activated, these cells release histamine and heparin
basophils
A substance that inhibits blood clotting and enhances the mobility of other WBCs in the area
heparin
The smallest of the granulocytes and are found in the lymphoid tissues and in circulating lymph and blood as well
lymphocytes
Two major types of lymphocytes
T lymphocytes and B lymphocytes (B cells)
Lymphocyte that is formed in the thymus and mainly works to rid the body of bacteria and viruses through direct invasion
T lymphocytes
Lymphocytes that are formed in the bone marrow and mainly work to rid the body of bacterial and viral organisms through the production of antibodies
B lymphocytes
One of the first lines of defense in the inflammatory process
monocytes
In response to infection, _____ migrate out of the blood vessels and into the tissues where they differentiate into macrophages
monocytes
A key component in the formation of clots, or coagulation
platelets (thrombocytes)
A protein hormone that is related to erythropoietin and controls platelet production.
thrombopoietin
Cells in the liver and kidneys secrete
thrombopoietin
Cessation of bleeding
hemostasis
What is the immediate physiologic response to bleeding?
vasoconstriction, to clamp down and cut off blood flow at the affected site
What happens if the bleeding proves to be a significant threat to homeostasis?
the adrenal glands release epinephrine (a potent vasoconstrictor), leading to systemic vasoconstriction
What is the secondary response to hemorrhage?
platelet plugging (the first platelets to be activated release chemicals that cause the aggregation (clumping) of additional platelets at the site of injury)
A set of interactions that lead to the formation of a clot
clotting cascade (coagulation cascade)
The two steps in the coagulation cascade that occur at the same time
extrinsic pathway and intrinsic pathway
The result of damage to the tissues, which then release clotting factors that react with other clotting factors and calcium.
extrinsic pathway (tissue factor pathway)
The final product of the extrinsic pathway
tissue thromboplastin
The result of damaged platelets releasing clotting factors that react with other clotting factors and calcium
intrinsic pathway (contact pathway)
The final product of the intrinsic pathway
platelet thromboplastin
Both tissue thromboplastin and platelet thromboplastin join at the common pathway, ultimately converting prothrombin (produced by the liver) to its active form, _____
thrombin
Thrombin acts on another blood protein called
fibrinogen
When activated, fibrinogen is converted into
fibrin
Long branching fibers that produce a weblike network in the wall of the damaged blood vessel
fibrin
The clot-dissolving portion of coagulation
fibrinolysis
What happens during fibrinolysis?
the enzyme plasminogen is converted to plasmin, which dissolves the fibrin fibers of the clot
Any process that interferes with the activation or continuation of the clotting cascade or hemostasis is known as
coagulopathy
Bleeding disorders that can lead to heavy or prolonged bleeding
coagulopathies
The RBC classification types are O, A, B, and AB, which indicate the antigens found in the plasma embrane
ABO system
RBCs contain _____ on their surfaces
antigens
The process of classification based on the presences or absence of specific antigens
blood typing
Blood that contains RBCs with type A surface antigens and plasma containing type B antibodies
Type A blood
Blood that contains type B surface antigens and plasma containing type A antibodies
Type B blood
Blood that contains both types of antigens but the plasma contains no ABO antibodies
Type AB blood
Blood that contains neither A or B antigens but contains both A and B plasma antibodies
Type O blood
Blood that has no ABO antigens and can be given to anyone, also known as a universal donor
Type O blood
Blood that has no ABO antibodies and is known as the universal recipient
Type AB blood
The secondary antigen in blood
Rh antigen (discovered in rhesus monkey)
Antigen that determines the immune response
Rh antigen D (Rh factor)
Sits in the chest, above the diaphragm, behind and slightly to the left of the lower sternum
the heart
The tip of the heart
apex
The top of the heart
base
The large vessels that carry blood to the heart
the superior and inferior venae cavae (vessels that return venous blood from the upper and lower parts of the body to the right atrium), and the pulmonary veins (vessels that return oxygenated blood from the lungs to the left atrium)
The large vessels that carry blood away from the heart
the aorta (which delivers blood from the left ventricle to the body) and the pulmonary arteries (which deliver unoxygenated blood from the right ventricles to the lungs)
A thick fibrous membrane that surrounds the heart
pericardium (pericardial sac)
The two membranes of the pericardium
outer fibrous membrane (parietal) and the inner membrane (visceral)
Between the parietal and visceral layers is the ______ ______, containing a small volume of serous fluid that reduces friction between the pericardial membranes as the heart moves within them.
pericardial cavity
The wall of the heart consists of three layers:
the epicardium (outer layer), the myocardium (the middle layer), and the endocardium (the inner layer)
This protects the heart by reducing friction
the epicardium (outer layer)
The four chambers of the heart:
the left and right atria (the two receiving chambers) and the left and right ventricles (the two pumping chambers)
The heart is divided into right and left halves by a tough piece of tissue called the
septum
What separates the two atria?
the interatrial septum
What separates the right and left ventricles?
the interventricular septum
Long, branching cells that fit together tightly at intercalated disks
cardiac muscle fibers
The four valves of the heart:
two atrioventricular (AV) valves (right AV valve is the tricuspid valve and the left AV valve is the mitral valve or bicuspid valve); and two semilunar (SL) valves (the right SL valve is the pulmonic valve and the left SL valve is the aortic valve) *T, P, M, A mnemonic is (toilet paper my ass)
These valves direct the flow of blood between the chambers and also prevent backward flow during ventricular contraction (regurgitation)
the right AV valve (tricuspid valve) and the left AV valve (mitral or bicuspid valve)
Fibrous bands of tissue attached to each part, or cusp of the valve
chordae tendineae
Attached to the chordae tendineae and the endocardium of the ventricles are
papillary muscles
These valves separate the ventricles and their associated great vessel and have three cusps
the SL valves (the right SL which is the pulmonic valve) and (the left SL valve which is the aortic valve)
The AV valves are closed during
ventricular contraction (ventricular systole)
Blood enters the right atrium by way of the
superior and inferior venae cavae and the coronary sinus
Where is oxygen and carbon dioxide exchanged?
the alveolar-capillary membrane
The left atrium receives oxygenated blood from the lungs by
the four pulmonary veins (two from the right lung and two from the left lung)
A repetitive pumping process that includes all the events associated with blood flow through the heart
cardiac cycle
The two phases of the cardiac cycle
systole and diastole
The period during which the chamber is contracting and blood is being ejected
systole
The period of relaxation during which the chambers are allowed to fill
diastole
The efficiency of the heart may be affected by
abnormalities of the cardiac muscle, the valves, or the conduction system
Blood flows from one heart chamber to another if the pressure in the chamber is
more than the pressure in the next
The conduction system of the heart provides the necessary timing of events between
atrial and ventricular systole
The low pressure right side of the heart is responsible for
pulmonic circulation
The high pressure left side of the heart is responsible for
systemic circulation
As both atria undergo systole, the ventricles are in
diastole
As both ventricles undergo systole, the atria are in
diastole
The first heart sound (lub)
S1
The second heart sound (dub)
S2
Occurs near the beginning of ventricular contraction (systole) when the tricuspid and mitral valves close
S1
Occurs near the end of ventricular contraction (systole) when the pulmonary and aortic valves close
S2
When S3 is heard in older adults, it is often associated with abnormally increased filling pressures in the atria secondary to
moderate to severe heart failure
The S4 sound represents either
decreased stretching of the left ventricle or increased pressure in the atria
An abnormal whooshing sound heard over the heart that indicates turbulent blood flow through the heart valves
murmur
An abnormal whooshing sound heard over a main blood vessel that indicates turbulent blood flow within the blood vessel, (often indicates localized atherosclerotic disease)
bruit
Indicate abnormal cardiac valve function
ejection clicks and opening snaps
The amount of blood that is pumped by the ventricles in 1 minute
CO cardiac output
The amount of blood pumped out by either ventricle in a single cardiac contraction (heartbeat)
SV stroke volume
The number of cardiac contractions per minute (the pulse rate)
HR heart rate
The percentage of blood that leaves the heart each time it contracts
EF ejection fraction
The volume of blood in the ventricle at the end of diastole and is primarily a reflection of venous return
preload (end-diastolic volume)
The force against which the ventricles must contract to eject blood
afterload
When cardiac muscle is stretched, it contracts with greater force to a limit, a property called
the Frank-Starling mechanism or Starling’s law
What is the Cardiac Output equation?
CO = SV x HR
The heart can vary the degree of contraction of its muscle without changing the stretch on the muscle, a property called
contractility
Refers to affecting the contractility of muscle tissue
inotropic
Related to the effect of the rate of contraction of the heart
chronotropic effect
The pressure that the blood exerts against the walls of the arteries as it passes through them
blood pressure
One mechanism of evaluating the effectiveness of CO is
the measure of blood pressure
The resistance to blood flow within all of the blood vessels except the pulmonary vessels
systemic vascular resistance
