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158 Cards in this Set

  • Front
  • Back
"internal sea" of the body
circulatory system
3 Major Parts of the Circulatory System
A fluid that serves as a medium of transport
a system of channels that conduct the blood throughout the body
blood vessels
a pump that keeps the blood circulating
two major types of circulatory systems:
open and closed
____ circulatory systems are present in invertebrates
An animal with an open circulatory system has one or more hearts, a network of blood vessels, and a large open space within the body called a
____ circulatory systems are present in some invertebrates; but mostly vertebrates
In closed circulatory systems, the blood (whose volume in only 5% to 10% of body volume) is confined to ___ and ___
heart and blood vessels
the ____ system supports all the other organ sytems in the body
chambers of the heart called ____ collect blood
Chambers of the heart whose contractions circulate blood throughout the body
blood that has picked up oxygen from the lungs/gills
blood without oxygen
parts of 3 chamber heart
2 atria and 1 ventricle
warm-blooded animals need a 4 chamber heart to meet a certain demand which is?
high metabolic rate...need more blood & faster
One pump [or side of the 4 chamber heart] consists of the __ and __ wich deal with deoxygenated blood from the body
right atrium
right ventricle
the right atrium receives oxygen-depleted blood form the body through to large __: superior vena cava and inferior vena cava
vessels that carry blood toward the heart
contractions of the right atrium force the blood to enter the
right ventricle
contractions of the right ventricle sends the oxygen-depleted blood to ___ via ___
the lungs via the pulmonary arteries
vessels that carry blood away from the heart
one pump [side of the 4 chamber heart] consists of the ___ and __ and deals with oxygenated blood
left atrium
left ventricle
Oxygen-rich blood from the lungs enters the left atrium through ___ and then is squeezed to the ___
pulmonary veins
left ventricle
the hearts most muscular chamber
left ventricle
contractions of the left ventricle send the oxygenated blood coursing out through a major artery the ___ to the rest of the body
the human heart beasts about ___ times each day
parts of the cardiac cycle
atriums contract
ventricles contract
atra and ventricles relax
At a normal resting heart rate, the cardiac cycle lasts
just under 1 second
the cardiac cylce is involved in _____ measurement
blood pressure
systolic pressure
the highter of the two readings--measured during ventricular contraction
diastolic pressure
measured between contractions
___ maintain the direction of blood flow in the heart
____ coordinate the sequence of contractions
electrical impulses
___ valves allow blood to flow from the atria to into the ventricles
____ valves allow blood to enter the pulmonary artery and the aorta when the ventricles contract
The contraction of the heart is initiated and coordinated by a ____, a cluster of specialized heart muscle cells that produce spontaneous electrical signals at a regular rate
The heart's primary pacemaker is the
sinoatrial (SA) node
where is the sinoatrial node located?
in the upper wall of the right atrium
Individual cardiac muscle cells communicae directly with one another through
gap junctions
How is the delay between the atria contracting and the ventricles contracting produced?
atrioventricle node
a small mass of specialized muslce cells locatted in the floor of the right atrium
atrioventricle node
Uncoordinated, irregular, weak contractions of the heart
measures the electrical activity underlying the contractions of the heart
electrocardiogram (ECG)
Plasma Protein which helps maitain the blood's osmotic pressure
Plasma protein which transports nutrients and plays a role in the immune system
Plasma Protein which is important in blood clotting and
Red Blood Cells carry oxygen fomr the ____ to the ____
lungs to the tissues
most abundant cells in the blood
red blood cells
red blood cells are also called
Why do red blood cells have a "hole"
lose their nunclei during develop
why is the "hole" good for the red blood cells
allows for great surface area

better absorption and release of oxygen and nutrients
the red color of the erythrocytes is caused by the pigment
large, iron-containing protein accounts for about one-third of the weight of each red blood cell and carries 97% of bloods oxygen
One hemoglobin molecule can bind and carry up to ___ molecules of oxygen
oxygen concentration high in blood capillaries or tissues of the body?
blood capillaries
Red blood cells are formed in
the bone marrow
Erythrocytes have an average life span of about _____
4 months
every second, more than ____ (#) red blood cells die and are replaced by new ones from the bone marrow
2 million
Dead or damaged red blood cells are removed from ciruculation, primarily in the ___ and ___, and broken down to release their ___
liver and spleen
____ regulates red blood cells numbers
negative feeback r
a hormone produced by the kidneys and released into the blood in response to oxygen deficiency
Blood is classified as type A, B, C, AB, or O, depending on the presence or absence of specific glycoproteins on the plasma mebrane of ____ cells
red blood cells
Rh-positive blood dominant or reccessive trait?
there are __ different types of white blood cells
white blood cells are also called
All white blood cells are derived from cells that originate in the _____
bone marrow
Most white blood cells function in the same way: ____
to protect your body from microbes
White blood cells use the _____ to travel to the site of invasion
circulatory system
type of white blood cell that change into amoeba-like cells after leaving the capillaries. they engulf foreign particles
"big eaters"
macrophages usually die after engulfing the foreign particle and their dead bodies accumulate to form
type of white blood cell that are responsible for the production of antibodies that help provide immunity against
macrophages engulf the foreign particle by ______
2 different types of lymphocytes
T Cells
B Cells
B cells are produced in the ___ and differentiated in _____
bone marrow
bone marrow
T cells are produced in the _______ and differianted in the _______
bone marrow
thymus gland [part of lymphatic system]
type of white blood cell that kills cancer cells and cells with an viral infection
Natural Killers
How do to Natural Killers kill the infected cells?
by secreting enzymes
type of white blood cell that "mops up" dead cells, dying cells, cellular debris, and microbes
cell fragments that aid in blood clotting
platelets are pieces of large cells called
platelets lack a _____
life span of platelets?
10-12 days
do megakarycytes stay in bone marrow or leave with platelets
stay in bone marrow
complex process that keeps animals fomr bleeding to death, not only from trauma, but also from normal wear and tear on the body
blood clotting
the process of blood clotting
1. tissue damage ruptures cells and causes platelets to aggregate

2. ruptured cells release chemicals that stimulate production of thrombin

3. aggrgated platelets release chemicals that stimulate production of throbin

4. thrombin catalyzes the conversion of fibrinogen to fibrin

fibrin traps platelets and red blood cells to aggregate and for a scab on top of the aggregated platelets
blood flows in well-defined channels called
blood vessels
As it leaves the heart, blood travels from ___ to ____ to ___ to ___ to ____, which return it back to the heart
arteries to
arterioles to
capillaries to
venules to
___ and __ are thick-walled vessels that carry blood away from the heart
Arteries carry blood ___ (to) (from) the heart
away from
arteries branch into vessel sof smaller diameter called
blood vessel that plays a major role in determining how blood is distributed within the body
microscopic vessels that allow the blood and body cells to exchange nutrients and wastes
arterioles conduct blood to ____
the tiniest of all blood vessels
where the actual process of diffusion occurs in the blood
what causes interstitual fluid to leak out of the capillaires on the aterioles sie?
high pressure within the capillaires
charged molecules cannot diffuse through the capillary membranes..where do they travel?
in the interstitual fluid around adjacent capillaries
why can't large plasma proteins, red blood cells, and platelets leave the capillaries
too large to fit through plasma membrane channels
the exchange of materials between capillary blood and nearby cells occurs through ____, which bathes nearly all the body's cells
interstitual fluid
pressure within the capillary drops as blood travels toward the _____
what does the high osmotic pressure of the blood that remains inside the capillaries do??
draws water back into the vessels by osmosis as blood approaches the venous end of the capillaries
much of the interstitual fluid is restored to the bloodstream thorugh the capillary walls on the ____ side of the capillary metwork
____ and _____ carry blood back to the heart
venules and veins
why does contractions of skeletal muscle during exercise and breathing help return blood to the heart by squeezing the veins and forcing blood through them?
because blood pressure is low in the veins
long periods of inactivity can contribute to the formation of _____, in which the vavles become stretched and weakened and the veins become permanetly swollen
varicose veins
Musculare arteriole walls are under the influence of ____, _____, and _____ produced by nearby tissues
the flow of blood in capillaries is regulated by tiny rings of smooth muscle called ______
precapillary sphincters
Precapillary sphincters srround the junctions between ____ and ____
arterioles and capillaries
3 main purposes of lymphatic system:
return excess fluid & dissolved substances that leak from the capillaries to the bloodstream

transport fats from the small intenstine to the bloodstream

defend the body by exposing bacteria and viruses to white blood cells
_____ resemble the veins and capillaries of the circulatory system
lymphatic vessels
two organs considered part of lymphatic system
chest pain associated with reduced blood flow to the heart muscle, caused by the obstruction of coronary ateries
a small artery that empties into capillaries. contraction of this blood vessel regulates blood flow to various parts of the body
a vessel with muscular, elastic walls that conducts blood away from the heart
a disease characterized by the obstruction of arteries by cholesterol deposits and thickening of the arterial walls
a specialzed mass of muscle @ the base of the right atrium through which the electrical activity iniated in the sioatrial node is transmitted to the ventricles
atrioventricular (AV) node
a heart valve that separates each atrium from each ventricle, preventing the backflow of blood into the atria during ventricular contraction
atrioventricle valve
a chamber of the heart that received venous blood and passes it to a ventricle
a fluid consisting of plasma in which blood cells are suspended; carried within the circulatory system
a complex process by which platelets, the protein fibrin, and red blood cells block an irregular surface in or on the body, such as damaged blood vessel, sealing the wound
blood clotting
a channel that conducts blood throughout the body
blood vessel
the smallest type of blood vessel, connecting arterioles with venules. capillary walls, through which the exchange of nutrients and wastes occur, are only one cell thick
the alternation of contraction and relaxation of the heart chambers
cardiac cycle
the type of circulatory system, found in certain worms and vertebrates, in which the blood is always confined within the heart and vessels
closed circulatory system
a red blood cell, active in oxygen transport, that contains the red pigment hemoglobin
a hormone produced by the kidneys in response to oxygen difiency that stimulates the production of red blood cells by the bone marrow
a clotting protein formed in the blood in response to a wound; binds with other fibrin molecules and provides a matrix around which a blood clot forms
the inactive form of the clotting protein fibrin. is converted into fribrin by the enzyme thrombin, which is produced in response to injury
a muscular organ responsible for pumping blood within the circulatory system throughout the body
a severe reduction or blockage of blood flow through a coronary atery, deprving some of the heart muscle of its blood supply
heart attack
a blood cavity within the bodies of certain invertebrates in which blod bathes tissues directly; part of an open circulatory system
the iron-containing protein that gives red blood cells their color; binds to oxygen in the lungs and releases it to the tissues
arterial blood pressure that is chronically elevated above the normal level
fluid, similar in composition to plasma [except lacking large proteins], that leaks from capillaries and acts as a medium of exchange between the body cells and the capillaries
interstitual fluid
any of the white blood cells circulating in the blood
a pale fluid, within the lymphatic sysem, that is composed primarily of interstitual fluid and lymphocytes
a system consisting of lymph vessels, lymp capillaries, and lymph nodes, and the thymus and spleen; helps protext the body against infection, absorbs fats, and returns the excess fluid and small proteins to the blood circulatory system
lymphatic system
a small structure that filters lymph; contains lymphocytes and macrophages, which inactivate foreign particles such as bacteria
lymph node
a type of white blood cell that engults microbes and destroys them by phagocytosis; also presents microbial antigens to T cells, helping stimulate the immune response
a type of circulatory system found in some invertebrates, such as arthropods and mollusks, that includes an open space [the hemocoel] in which blood directly bathes body tissues
open circulatory system
a cluster of specialized muscle cells in the upper right atrium of the heart that produce spontaneous electrical signals at a regular rate; the sinoatrial node
a deposit of cholesterol and other fatty substances within the wall of an artery
the fluid, noncellular portion of the blood
a cell fragment that is formed from megakarycytes in bone marrow and lacks a nucleus; circulates in the blood and plays a role in blood clotting
a ring of smooth muscle between an arteriole and a capillary that regulates the flow of blood into the capillary bed.
precapillary sphincter
a protein on the red blood cells of some people (__-postive) but not other (__-negavitive); the exposure of _-negative individuals to _-positive blood triggers the production of antibodies to __-positive blood cells
Rh factor
a paired valve between the ventricles of the heart and the pulmonary arer and aorta; prevents the backflow of blood into the ventricles when they relax
semilunar valve
a small mass of specialized muscle in the wall ofthe right atrium; generates electrical signals rhymically and spontaneiously and serves as the heart's pacemaker
sinoatrial (SA) node
an organ of the lymphatic system in which lymphocytes are produced and blood is filtered past lymphocytes and macrophages, which remove foreign partricles and aged red blood cells
an interruption of blood flow to part of the brain caused by the rupture of an artery or the blocking of an artery by a blood clot. loss of blodd supply leads to rapid death of the area of the brain affected
an enzyme produced in the blood as a result of injury to a blood vessel; catalyzes the production of fibrin, a protein that assists in blood clot formation
an organ of the lymphatic system that is located in the upper chest in fron of the heart and that secretes thymosin, which stimulates lymphocyte maturation; begins to degenerate at puberty and has litte function in the adult
a patch of lymphatic tissue consisting of connective tissue that contains many lymphocytes; located in the pharynx and throat
in vertebrates, a large-diameter, thin-walled vessel that carries blood from venules back to the heart
the lower muscular chamber on each side of the hear, which pumps blood out through the arteries. the right ventricle sends blood to the lungs; the left ventricle pumps blood to the rest of the body
a narrow vessel with thin walls that carries blood from capillaries to veins