BMS 251 Exam 2
_________________ involves bulk flow of fluid out of the blood, whereas __________________is bulk flow back into the blood.
Filtration Reabsorption
Describe the arterial end of a capillary bed.
Filtration dominates and is driven by hydrostatic pressure
Compare filtration and reabsorption
Filtration involves bulk flow of fluid out of the blood, whereas reabsorption is bulk flow back into the blood.
attack abnormal and infected body cells
Natural Killer cells
The exchange of nutrients and gases between the blood and tissue cells is the primary function of
capillaries
The structure of a capillary wall differs from that of a vein or artery because
capillary walls have only endothelium and a basement membrane.
which baroreceptors are more sensitive to blood pressure changes?
carotid sinus baroreceptors
which baroreceptors monitor the BP changes in the head and neck and are important in monitoring the BP that affects the brain?
carotid sinus baroreceptors
Valves in veins
cause venous blood flow to go in only one direction
leukocytes are attracted to the site of infection by molecules released by dead cells, damaged cells, or invading pathogens. This is called
chemotaxis
arteries and veins that supply the same body region tend to lie next to one another and are called
companion vessels
When sphincters are ___________, blood bypasses capillary bed
constricted
Which is the most common type of capillary?
continuous
Oxygen and carbon dioxide are transported between the blood and interstitial fluid by way of
diffusion from areas of higher concentration to lower concentration.
Oxygen and carbon dioxiode are transported between the blood and interstitial fluid by way of
diffusion from areas of higher concentration to lower concentration.
Fibrinogen gets converted to ___________, which has what function?
fibrin -polymer -long strong cords that wrap around platelet plug =clot
following trauma to the walls of blood vessels, ______________ is converted into long, soluble strands of ____________, which help form a blood clot
fibrinogen fibrin
To destroy the fibrin framework of the clot, plasmin degrades the fibrin strands through __________________
fibrinolysis
colony-stimulating factors
influences the maturation and division of hemopoeic stem cells
Net filtration pressure (NFP) is equal to the
net hydrostatic pressure minus the net colloid osmotic pressure.
Considering the bulk flow that occurs at capillary beds, the lymphatic system is needed to
reabsorb excess fluid from the interstitial fluid
oxygen rich blood is bright red/scarlett due to
the oxidation/reduction of iron in the blood
The most important force in venous flow is
the pressure generated by the heart.
Blood colloid osmotic pressure is largely due to
the proteins in the blood, and it promotes reabsorption.
What blood vessel type serves as a storage area for blood?
the veins
Arteriosclerosis is characterized by
thickening of the tunica intima and loss of elasticity in the tunica media.
Which kind of vessel provides a bypass for a capillary bed?
thoroughfare channel
The iron component of the RBC is removed and transported to the liver by a protein called
transferrin
Beta globulins
transport iron ions and lipids in blood
Alpha globulins
transport lipids and some metal ions
When medication is taken, the blood delivers it to body cells. What function of blood does this describe?
transportation
True of false: At rest, most blood is within the venous system.
true
True or false: The contraction of skeletal muscles play an important role in the movement of blood in the veins.
true
The ____ is composed of an endothelium and a subendothelial layer made up of a thin layer of areolar connective tissue.
tunica intima
Which coat of an artery contains endothelium?
tunica intima
Arteries can constrict or dilate as needed because of the smooth muscle found in the
tunica media
Distributing arteries contain a thick ____.
tunica media
In arteries, the thickest layer of the wall is the
tunica media
The ___ is composed of circularly arranged layers of smooth muscle cells.
tunica media
Valves similar to the semilunar valves of the heart are found in medium and large ____.
veins
Waste products are taken up by the capillaries at their ___ end.
venous
centrifuge separates blood based on
weight
What is the most important means by which capillary exchange occurs?
diffusion
Most blood is in the
veins
How to fix high BP?
-ACE inhibitor stunts ANG II formation and everything else cons: effects are too global can make BP too low b/c baroreceptors can mediate BP quickly but they aren't long lasting -ANG II receptor block blocks vasoconstriction eliminates cascade of blockages and allows just the receptor to be blocked
3 functions of erythrocytes
-O2 transport -acid/base regulation -CO2 transport
Thromboxane A2
-actinomyosin a contractile protein that squeezes platelet plug together -squeezes out any fluid/plasma -makes platelet plug tighter
process of recycling/elimination of erythrocyte components
-aged erythrocytes are phagocytize by macrophages -the three components of hemoglobin (heme, iron, globes) are separated -iron is stored in liver attached to ferritin and transported to red bone marrow as needed -globin proteins are broken down into amino acids released into blood; may be used to make RBCs -bilirubin is transported by albumin then released as a component of bile--> urobnillinogen in small intestine --> stercobilin and expelled in feces
Where are the two baroreceptors located?
-aortic artch -carotid sinus
respiratory pump
-assists the movement of blood within the thoracic cavity -when the diaphragm contracts and flattens, intra-abdominal pressure increases and places pressure on vessel in abdominal cavity -thoracic volume increases -intrathoracic pressure decreases
these are the short term mechanisms for BP regulation
-autonomic reflexes involving nuclei within the medulla oblongata
component of capillary
-basement membrane -endothelium
how does the greater amount of muscle in the muscular arteries affect them differently than the elastic arteries?
-better ability to vasoconstrict and vasodilatate -lessened ability to stretch
How EPO regulates erythrocyte production
-blood O2 levels can decrease due to high altitude, removal of aged RBCs, or blood loss -the kidney detects the low blood oxygen -kidney cells release EPO into the blood -EPO stimulates myeloid cells in the red bone marrow to increase rate of erythrocyte production -net effect: increased number of erythrocytes into a circulation, lungs oxygenate blood and the blood O2 increases
consequence of lack of plasma proteins
-causes osmotic pressure to decrease -fluid retention in interstitial space
continuous capillaries
-complete lining of endothelial cells around lumen -plasma and its components & some leukocytes pass through vessel wall -found in most capillaries
how do you vet a BV to vasodialate
-decrease firing of sympathetic nervous system -decrease norephinephrine
What occurs regarding the baroreceptors when the blood pressure decreases?
-decreased stretch in the blood vessel walls -barorecepters decrease frequency of firing rate -sympathetic system stimulates an increase in HR, SV, and CO -blood vessels vasoconstrict -increase in peripheral resistance -blood leave venous reservoirs and enter circulation
blood flow is ____________ (directly/inversely) related to pressure gradient
-directly -as BP gradient increases, total blood flow increases
direct stimulation (vasodilation)
-directly stimulating arterioles to dilate
process of vesicular transport
-endothelial cells use pinocytosis to form fluid-filled vesicles that are transported to the other side of the cell and released via exocytosis
Kidneys release this enzyme that binds to a substrate in the liver, which makes Angiotensin I
-enzyme= renin -substrate= Angiotensinogen
structures that have no capillaries
-epithelial tissue, cartilage, cornea/lens in eye
Albumin
-exerts osmotic force to retain fluid in blood -contributes to blood viscosity -responsible for fatty acid and hormone transport
hydrostatic pressure
-force exerted per unit area by the blood as it presses against the vessel wall -promotes filtration from the capillary
blood flow is _____________ (directly/inversely) related to resistance
-inversely -if resistance increases, blood flow decreases
Which organ works to make sure that the MAP stays relatively constant?
-kidneys
sinusoid capillaries
-lining of endothelial cells incomplete around lumen -basement membrane incomplete or absent -large substances, formed elements, and large plasma proteins can pass through -found in: red bone marrow, spleen, liver
differential count
-measures the amount of each type of leukocyte in blood -determines whether or not any circulating leukocytes are immature -useful in diagnosing conditions such as cancer
leukopoiesis involves these three types of maturation
-monocyte -lymphocyte -granulocyte
Fibrinogen
-participates in blood coagulation
Gamma globulins
-participates in blood coagulation
Autoregulation
-process by which a tissue regulates itself or controls its local blood flow in response to changing metabolic needs -inadequate perfusion due to increased metabolic activity of tissue -causes nutrient levels and oxygen levels to decrease -levels of CO2, H+, and lactate increase -vasodilation occurs -more blood enters capillaries -perfusion increases in tissues -regulated through negative feedback
These vasoactive chemicals cause vasoconstriction
-prostaglandins and thromboxanes -help prevent blood loss from damaged vessels
The return of blood vessels to their previous state. (ex: when a once physically active person becomes sedentary)
-regression
thickness of blood (viscosity) depends on
-relative % of particles in fluid and their interactions with one another
stimulation of the adrenal medulla by the sympathetic system causes
-release of epinephrine and norepinephrine -increased peripheral resistance -larger circulating blood volume -redistribution of blood flow: more to active muscles and heart, less to inactive muscles
fenestrated capillaries
-same as continuous but also contain fenestrations -large amounts of materials are filtered, released, and reabsorbed -some smaller proteins pass through vessel wall -found in: small intestine, ciliary process, choroid plexus, most endocrine glands, kidneys
Plasmin role in clot retraction
-scissors that cuts the fibrin polymer -allows healthy cells to replace the fibrin clot
adult red bone marrow is found where
-sternum -vertebrae -roofing bones of the skull
Angiotensin II
-stimulates thirst, hypothalamus to release ADH (causes water retention in kidneys)
this vasoactive chemical causes vasodilation via indirect stimulation
-stimulating endothelial cells of vessel to release nitric oxide which causes vasodilation
How does the body attempt to maintain blood pressure when over 10% of blood volume is lost?
-sympathetic division of ANS is activated -blood vessels vasoconstrict, HR increases, and there is an increased force of contraction in the heart
TPA-tissue plasmin activator
-takes plasminogen in circulation to active plasmin -plasmin does fibrinolysis
When muscles are inactive, what happens to the blood in the veins?
-the blood pools in the veins -increased risk of deep vein thrombosis
colloid osmotic pressure
-the pull of water back into the tissue via osmosis due to the tissue's concentration of proteins
If a patient has elevated levels of hematocrit, what does that mean?
-they are either dehydrated or participating in blood doping
components of artieries
-tunica intima -tunica media -tunica externa
reactive hyperemia
-when local blood flow is restored, there is an increased blood flow to affected tissue -resupplies tissue with O2 and nutrients -eliminates accumulated wastes -ex: when checks turn red when entering warm room after being in the cold
Blood loss greater than _____% results in insufficient blood volume within the blood vessels, and BP decreases to levels unable to support life
40
This WBC secretes heparin, which prevents all blood from clotting
Basophil
become plasma cells and produce antibodies
B-lymphocytes
Tendons and ligaments have a a low degree of vascularization. What does this mean about their perfusion and healing?
Low perfusion Slow healing
manage and direct immune responses; attack infected and foreign body cells
T-lymphocytes
when erythrocytes are removed from circulation, what happens to the proteins that were in the plasma membrane?
They are broken down into amino acids, which can be used to make erythrocytes
Which are found in the capillary wall? a: Endothelium b: Subendothelial layer c: Internal elastic lamina d: Intercellular clefts e: External elastic lamina f: Basement membrane
a: Endothelium d: Intercellular clefts f: Basement membrane
clot retraction occurs as the clot is forming when __________________, a contractile protein, contracts and squeezes the plasma out of the developing clot
actinomyosin
Serotonin
activates other platelets to adhere to each other
angiogenesis is stimulated in ___________ ____________ which occurs due to the deposition of fat
adipose tissue
Exert the greatest colloid osmotic pressure to maintain blood volume and pressure
albumins
ACE
angiotensin converting enzyme -forms Angiotensin II
Y-shaped proteins that are designed to recognize and immobilize specific antigens that are perceived as foreign to the body
antibodies
Are arteries or veins more resilient to changes in blood pressure?
arteries
What is the order of the blood vessel that a red blood cell would pass through as the blood leaves the heart, travels to a tissue, and then returns to the heart?
artery, arteriole, capillary, venule, vein
Movement of blood flow through a capillary ved
artieriole --> met arteriole --> true capillaries --> thoroughfare channel --> post capillary venule
ANP
atrial naturetic peptide -released when atria stretches more (from high salt conc., water diffuses more, and there is a higher BP) -when volume is lower, pressures lower
bilobed; blue-violent dark staining cytoplasmic granules
basophil
why does a blood pressure gradient exist?
because blood pressure is highest in arteries and lowest in veins
Why Is the blood pressure gradient in veins insufficient to move blood through veins without assistance?
because the blood pressure gradient is very small
The most important force driving reabsorption at the venous end of the capillary is
blood colloid osmotic pressure.
The most important force driving filtration at the arterial end of a capillary is
blood hydrostatic pressure
the relatively large amount of blood within veins allows veins to function as __________________ __________________
blood reservoirs
Sinusoids are found in
bone marrow, spleen, liver
Where are sinusoids found?
bone marrow, spleen, liver
vasoconstriction and vasodilation depends on receptors in smooth muscle cells of the tunica media of the BV wall. -stimulation of A1 receptors cause muscle cells to _______________ in response to norepinephine -stimulation of A2 receptors cause muscle cells to _____________ in response to norepinephrine
contract relax
What are the functions of the precapillary sphincters?
control blood flow into the true capillaries; cause blood to flow directly from the metarteriole into the postcapillary venule; open when the tissue needs nutrients; close when the tissues needs have been met
Precapillary sphincters
control the blood flow into capillary beds.
functions of lymphocytes
coordinate immune responses attack abnormal body cells
What would lead to relaxation of the precapillary sphincter?
decreased oxygen levels in tissue cells served by the capillary
As blood moves from the arterial end to the venous end of a capillary, net filtration pressure _________________ (decreases/increases) as blood hydrostatic pressure _________________ (decreases/increases)
decreases decreases
Leukocytes participate in the process of _____________, or squeezing through endothelial cells of BV walls
diapedesis
Filtration
dominates at the arterial end of a capillary bed and is driven by hydrostatic pressure.
The function of the postcapillary venule is to
drain the capillary bed
The blood vessels that are under the greatest pressure are the
elastic arteries
From heart to body tissues, what is the correct sequence of vessels?
elastic artery, muscular artery, arteriole, capillary
The lining of a capillary is called the
endothelium
This WBC helps rid the body of parasites
eosinophil
This WBC phagocytosis everything that isn't "you" and plays a role in allergic reaction
eosinophil
lower layer in centrifuge
erythrocytes/formed elements makes up 44%
this type of RBC have specific granules in their cytoplasm
granulocytes
Compared to veins, arteries
have a thicker tunica media, a narrower lumen, and more elastic and collagen fibers
% of all formed elements in the blood
hematocrit
-a pigment -a protein -transports O2 and CO2 -is suspended in the cytosol of erythrocytes
hemoglobin
If someone were to have abnormally low levels of protein in their blood, then would the net filtration pressure be higher or lower than normal?
higher
why do adult males have a higher percentage of hematocrit?
higher level of testosterone= kidneys produce more EPO
This vasodilator increases cell permeability
histamine
basophil releases _________________, which can cause vasodilation
histamine
Filtration dominates at the arterial end of a capillary bed, and is driven by _______________ pressure.
hydrostatic
A portal system:
is one in which blood flows through two capillary beds before being sent back to the heart.
Why is blood considered a colloid?
it contains proteins in its plasma
why does water provide us with a stable medium blood-wise?
it has a high specific heat does not allow us to evaporate or boil easily
What organ works to regulate MAP
kidneys
____ arteries have the thickest tunica media.
large (or elastic or conducting arteries)
What components of the blood protect us from harmful substances?
leukocytes plasma proteins
high levels of these types of WBCs are indicative of chronic infection
monocytes
organs that are very metabolically active need ______________ (more/less) vascularization
more
Concerning the exchange between blood and interstitial fluid and systemic capillaries
more fluid is filtered and then reabsorbed.
This WBCs degranulate into lysosomal enzymes, proteases, and free radicals to help fight bacterial infections
neutrophil
increased levels of this will indicate a bacterial infection
neutrophils
Is there parasympathetic innervation of blood vessels
no
is oxygen a vasodialator?
no
is water thicker than blood?
no
how do you get a BV to vasoconstrict
norepinephrine
the cardioaccelatory center causes the release of ____________________ from ganglionic neurons, which __________ the firing rate of the SA node and ____________ the delay at the AV node. It also stimulates the myocardium to produce a more ________________ contraction
norepinephrine increases decreases forceful
The hepatic portal system is an unusual vein in that it is transporting ___.
nutrient-rich blood
which type of pressure (hydrostatic/osmotic) is relatively unchanging?
osmotic b/c of proteins
force responsible for drawing in fluids in blood and preventing excess loss from blood capillaries to the interstitial fluid
osmotic force
When capillary sphincters are relaxed, the capillary bed is well ___________
perfused
top layer in centrifuge
plasma straw-colored liquid makes up 55% of blood sample
_________________ cells can differentiate and develop into many types of cells
pluripotent cells
hemopoesis
process of making formed elements occurs in red bone marrow (myeloid tissue) begins in hemocytoblasts produces two lines: myeloid and lymphoid
Blood contains___________ and ___________ that exert osmotic pressure which pulls fluid back into capillaries
proteins and ions
Capillary walls serve as effective permeability barriers for
proteins.
heat is related at the body surface as blood is transported through the vessels of the skin. What function of blood does this describe?
regulation (of temp)
Arteries are sometimes called the ___ vessels of the cardiovascular system because they have strong-resilient tissue structure.
resistance
Endothelium
simple squamous epithelium of capillaries
angiogenesis is stimulated in ____________ ____________ in response to aerobic training
skeletal muscle
Vasomotion is associated with the presence of
smooth muscle in the tunica media.
A latticework of ____________ protein supports the membrane of the RBC on its internal surface and provides flexibility as it moves thru the capillaries
spectrin
Tissue damage can trigger local release of histamine, which can
stimulate the release of nitric oxide, a vasodialator
At a capillary bed, a vasoconstrictor:
stimulates precapillary sphincters and decreases local blood flow
Describe arteries
strong, elastic vessels that carry blood under high pressure
cause venous blood flow to go in only one direction.
valves in veins
A network of small arteries called the ___ provides a blood supply to the tunica externa of very large vessels.
vasa vasorum
This network of small arteries provides a blood supply to the tunica externa of very large vessels
vasa vasorum
Blood flow is increased by
vasodilation
carbon dioxide causes ___________________
vasodilation increases perfusion to help rid the body of CO2
histamine, carbon dioxide, nitric oxide are examples of
vasodilators