Flashcards in PHYS 1 MIDTERM 1 Deck (500):
What is Physiology?
The study of living function.
About how many cell do humans have?
What is Homeostasis?
Maintenance of constant conditions within the body.
What does it mean to function as an automaton?
The vast Majority of operations are carried out by automatic control systems.
Physiology sometimes is thought of as the study of _______ systems.
What is the more typical approach to control systems?
Negative feedback involves what type of a response?
The negative feedback consists of what?
A sensor and an output system.
Negative feedback is like what system in a house?
The furnace. It is an on/off system
Homeostasis is a _____ balanced state of self-regulation.
For negative feedback the degree of effectiveness of the control is a function of what?
The "Gain" of the feedback system.
Negative feedback system leads to what?
How common is positive feedback and it leads to what?
Uncommon and leads to instability.
Positive feedback involves what type of response?
In the Positive or same direction.
Positive feedback leads to what?
a vicious cycle that circles until death.
When is positive feedback helpful?
in short-term situations like blood clotting and action potentials.
What does thrombocytopenia mean?
Low levels of platelets.
Idiopathic thrombocytopenia purpura is what type of disorder?
One of decreased platelet numbers. normal platelet numbers 200,000-400,000 down to 50,000 or less.
what are the 2 versions of idiopathic thrombocytopenia purpura?
Childhood version that seems to self-resolve Adult version needs ongoing therapy.
What are the signs of idiopathic thrombocytopenia purpura?
easy bleeding micro-bleeds easy brusing nosebleeds
What are the laboratory findings of idiopathic thrombocytopenia purpura?
Prolonged bleeding times anemia may develop deficient clot retraction.
What type of fluid is blood?
A transportation fluid.
What color is oxygenated and deoxygenated blood?
oxygenated = brighter red deoxygenated = darker red
What is the specific gravity of blood?
What is the ph and temperature of blood?
ph= 7.4 temp = 37 c or 98.6 f
How much more viscous is blood than water?
3-5 times more.
How much blood does the average person have?
5 liters 7.75% of body weight.
What % of blood is Plasma, WBC with platelets, and RBC?
Plasma= 55% WBC with platelets= very little RBC= 45 %
What is the thin veneer in the middle of a test tube of seperated blood called and made of?
Buffy coat made of Leukocytes and platelets.
The erythrocytes make up 45 % of the blood in a test tube and the volume of rbc in blood is known as?
What are the specific values for Hematocrit?
5,000,000 +- 500,000 per mm3
A decreased hematocrit is indicative of what?
You are considered anemic with a hematocrit count of how low?
4 million of lower
An increased hematocrit is indicative of what?
What is polycythemia?
A high amount of RBC.
What is the hematocrit count for polycythemia?
6 million or more.
Extreme polycythemia can result in what?
An interrupted blood flow to microvasculature.
Each RBC is packed with what, and what will it do?
Hemoglobin carries o2
How much hemoglobin is contained in 100 ml of blood?
Each RBC contains how much hemoglobin?
How much o2 can each rbc carry?
about 1 billion.
How many liters of o2 are found in the entire blood?
Total RBC numbers is a function of what?
What is erythropoiesis?
Making of RBC in Bone marrow.
What controls the amount of RBC made?
A hormone called Erythropoietin aka epo
Where is erythropoietin primarily produced at?
When will erythropoietin be made?
When blood oxygen is low the oxygen in the kidneys will be low and this signals the kidneys to make more erythropoitin.
Erythropoietin is an example of what type of feedback to maintain homeostasis?
What is physiologic polycythemia?
An increase in RBC in people who live in high altitudes.
What is hemoglobin made of?
It is a protein made of amino acids and Iron.
What is needed to make erythropoietin?
Vitamin b12 and folic acid.
How long will RBC last in the blood?
Without centrifuging blood just letting the RBC seperate out from the plasma and the WBC what would this process be called?
Erythrocyte sedimentation rate.
What is a normal erythrocyte sedimentation rate?
What would an increased erythrocyte sedimentation rate mean?
It is elevated during infection, cases of arthritis and inflammatory diseases.
Why will the erythrocyte sedimentation rate increase during infections?
Tissues release acute phase reactant proteins that stick on RBC and allow them to clump together and this increases the rate of sedimentation.
What besides water is the major component of Plasma?
What plasma protein helps with pressure of capillaries? And how? What is this called?
Albumins. The fluid will want to come inside the capillaries to establish an equillibruim with the albumins. Called Plasma colloidal osmotic pressure.
Plasma proteins are involved in what?
Carriers, defense, clotting/coagulation.
Name the 3 broad groups of Plasma proteins? List them in the order of smalles to largest.
Albumins, Glogulins, and Fibrinogens.
Nearly all the plasma proteins are made where?
In the liver.
What Plasma proteins help as a carrier function? what will they specifically bind?
Albumins. Fatty acids. Globulin
What are the 3 types of globulin?
alpha= a globulin Beta = b globulin gama = y globulin
List the 3 groups of plasma proteins starting with the least commn and ending with the most common.
Fibrinogen, Globulins, Albumins
Alpha a globulin does what?
Transports or carries: proteins, lipids (HDL), Steroid-binding proteins, and clotting factors.
Beta B globulin does what?
Transports or carries: Lipids (LDL), and Iron.
Beta B globulin carries iron as what?
Gama Y globulin does what?
it is a family of various antibodies.
What is fibrinogens main purpose?
Precursor to a clot.
clotting is a function of what?
Fibrinogen is a precursor to what?
What is fibrin?
A molecule that can polymerize to form an insoluble mesh used to minimize blood loss.
Fibrin does what to blood?
Coagulates it (turns from liquid to solid) aka clotting.
What happens to Fibrinogen to make a clott?
Fibrinogen ---------> Fibrin Monomer--------> Cross-linking fibrin Ca2+ Fibrin stabalizing and Thrombin Factor
What does hemostasis mean?
Blood same. This is the ability to maintain blood volume.
What 3 mechanisms help with hemostasis?
1. Vascular constriction. 2. Platelet 3. Clot formation.
What induces vasoconstriction?
Trauma to a vessels wall. This trauma releases a local vasoconstrictive factor from smaller vessels like endothelin-1.
How do platelets stimulate vasoconstriction?
They release thromboxane A2 and serotnin.
What will promote platelet aggregation to help make a platelet plug?
Thromboxane and thrombin.
While forming a platelet plug thrombin functions through what system?
Platelets are small fragments from where?
Bone marrow megakaryocytes.
What do Platelets have inside of them?
NO nucleus, but they have various organelles. They are also covered with lots of receptors.
What are the three processes a platelet goes throught when contacting a damaged vessel wall?
1. Adherence 2. Aggregation 3. Secretion.
What makes a platelet adhere to a damaged vessel wall?
Contact with damaged endothelia and contact with tissue proteins including collagen.
Simultaneous aggregation of platelets form what?
A Platelet plug
What are platelet plugs used for that clots are not?
Platelet plugs are useful in routine daily injuries that produce tiny holes in vessels.
Aspirin can effect platelets how?
It can inhibit platelet aggregation.
During normal hemostasis which pathway is used?
Both intrinsic and extrinsic pathways.
What are the major players in blood clotting besides factors?
Thrombin is the major player, but ca2+ and platelet phospholipids are also important.
What is calcium chelation?
A way to keep blood from clotting in a test-tube because it removes calcium and this stalls many clotting reactions.
What is the primary activation for the intrinsic pathway in blood clotting?
contact with collagen or trauma to the blood.
What is the primary activation for the extrinsic pathway of blood clotting?
Release of tissue factors.
How long will blood clotting take?
What makes the blood clotting system turn from positive feedback to negative feedback?
What specifically happens to Fibrinogen to make it fibrin?
Clipping off parts of Fibrinogen.
What is needed to change fibrinogen to fibrin?
ca2+ and thrombin.
What is needed to make thrombin?
You start with prothrombin and you need ca2+ and prothrombin activator. Then you get thrombin.
Prothrombin activator is a complex substance made of several molecules, but mostly what?
What has to happen to factor X for it to help make Prothrombin?
factor X ---------------> Factor Xa (a signals that it is the activated form) ca2+
What ways can prothrombin be activated?
Intrinsic pathway and Extrinsic pathway.
The intrinsic pathway used to activate prothrombin requires what factors?
IX, and VIIIa.
Which pathway is faster at activating prothrombin intrinsic or extrinsic?
Extrinsic pathway is the quickest.
Which pathway is most effective at activating prothrombin?
Intrinsic pathway because it is amplified.
which factors are required to use the extrinsic pathway?
The bl0od clotting system is an example of what type of feedback?
How is the endothelial lining of vessels engineered to act as a anti-clotting mechanism?
They are smooth simple squamous cells that are coated with glycocalyx which tends to repel clotting factors.
A formed clot will minimize blood flow to the area and how will this be an anti-clotting factor?
This will minimize the amount of clotting factors that can come into the area.
How will thrombin help with anti-clotting?
It will activate an alpha a globulin (plasma protein) called antithrombin III which will bind to thrombin and inactivate it in a delayed way that takes longer than clotting.
What will help antithrombin III destroy or inhibit thrombin? Where will it come from?
Heparin that comes from mast cells.
What is fibrinolysis?
Plasminogen is an inactive protease (a group of enzymes that degradates proteins) that will destroy fibrin when activated and this happens as fibrin is forming.
What is the active form of plasminogen and how is it activated?
Plasmin and it is activated by tpa
What is tpa? And where will it come from?
Tissue plasminogen activator. It is released from injured tissues a day or so later.
tPA has been commercially sold as a drug that is used for?
Acute heart attacks and strokes, but must be infused very soon after injury to be helpful.
What vitamin is required for synthesis of several clotting factors?
How is Vitamin K made?
By bacterial flora in the Intestine
What does coumarin do?
It is a competitive inhibitor for vitamin K sites in Hepatocytes. It is wrongly called a blood thinner it wont thin blood but it will minimize dangerous clotting in patients.
What results from a lack of factor VIII?
Hemophilia A and lots of uncontrolled bleeding.
What are 2 thromboembolitic conditions.
1. Thrombus 2. Embolism.
An abnormal clot that forms in vessels is called what?
What is an embolism?
A thrombus that breaks away and freely float in vessel.
Generally how will thromboembolic conditions arise?
From roughened endothelia or in area where blood moves slowly.
why is the platelet count down in Idiopathic thrombocytopenia pruprua?
They are destroyed and removed from the blood in the spleen.
What does idiopathic mean and why is idiopathic thrombocytopenia purpura idiopathic?
Unknown and the root cause of this disease is still unknown.
Why will people with idiopathic thrombocytopenia purpura have increased bleeding times?
Because they need platelets to participate in clotting pathways.
Why will people with Idiopathic thrombocytopenia Purpura bruse easy?
With low platelets they cant fix routine micro holes in the vessels and this leads to bleeding from membranes and dermal microvasculature.
What form of Idiopathic thrombocytopenia Purpura is more serious the childhood or adult form? And why?
Adult. Because of autoimmunity.
What are some treatment for idiopathic thrombocytopenia purpura?
Some receive a splenectomy. Some receive platlets. Some get corticosteroids.
How many children will show a functional murmur at some point in time?
How can you tell someone has a functional murmur?
Listen for a sound that can be heard during the ejection of blood from a normal heart. A noise between the lub and dub of the heart.
What specifically will the sound of a functional murmur sound like?
short and twangy low-pitched sound.
A functional murmur will often be seen with what other conditions?
Anxiety, stress, fever, anemia, hyperthyroidism, or pregnancy.
What is the physics formula for flow?
Q=delta P/R Q= flow Delta P = pressure differential R= vascular resistance.
What happens to Q (flow) if R (vascular resistance) is increased?
IT goes down.
How can we solve for R (vasculature resistance)?
R= 8nL/pi r^4 n= viscosity L= length r= radius
viscosity of blood is just a function of what?
Hematocrit (a measure of what percentage of blood is RBC).
What is more viscous plasma or water and why?
Plasma because of proteins.
What is the formula for blood flow after we take out all the factors that can't be changed?
Q = r^4
What is the single greatest determinant of blood flow through a vessel?
The diameter (or Radius).
Doubleing the diameter of a blood vessel will increase its flow by how much and why?
16 fold because the formula Q=r^4 and the radius is raised to the fourth power.
The normal result of blood flow moving through vessels takes what kind of profile?
a Parabolic velocity profile.
If a barrier was removed from a blood vessel what blood will travel the fastest and why?
The blood in the middle because there is not drag from the walls.
What is the name of the flow when blood moves faster in the middle and slower as we move towards the walls?
What are the qualities of laminar flowing fluids?
Very efficient, smooth, and quiet.
What happens when the streamlines of flowing blood are disturbed?
We get turbulent flow.
What are the qualities of turbulent flow?
Inefficient, rough, and noisy.
Noise from turbulent flow in vessels and in valves is known as what?
Vessels = bruit valves = murmur
Turbulent flow typically happens when?
With obstructions and high velocity.
Obstructions will disturb laminar streamlines into what?
What is stenosis and what will it cause?
A narrowing and it causes the velocity to increase and the total flow to decrease.
When we increase the diameter of a blood vessel what happens to flow and what happens to pressure of the blood upstream?
The flow will increase, but the pressure upstream will decrease as more blood is flowing through.
What other agents will help convert or activate plasminogen besides tPA?
What is Reynolds number?
The point when turbulence happens.
What is the destabilizing factor in reynolds number?
How will shear force effect blood flow?
Normaly it is minimal, but with turbulence (exceeding reynolds number) it causes clotting and additional injury.
What is carotid artery stenosis? what will it cause? how common is it?
The carotid artery becomes occluded by fatty plaque. It can cause a ischemic stroke common in aging process
During carotid artery stenosis what is reynolds number like?
It is exceeded and turbulence happens.
What are korotkoff sounds?
Normal arterial noises heard during routine assessment of blood pressure using the ausculatory method and using a sphygmomanometer and a stethoscope.
What is auscultation?
Listening to beats with the stethoscope.
What is compliance when talking about blood vessels?
Intravascular pressure that stretches blood vessels in proportion to their ability to absorb more blood.
How is compliance numerically defined?
a change in volume per a change in pressure: Compliance= delta V/delta p
What is more compliant an artery or a vein?
Arteries are not very compliant Veins are very compliant.
What type of stimulation can modify the performance of vessel systems?
What percentage of our blood is found in Veins/venules, and arteries/arterioles?
Veins/venules= 64% or about 2/3 artery/arterioles= 15%
What is the aorta used for?
Pulse dampening and distribution.
What are large arteries used for?
Pulse dampening and distribution.
What are small arteries used for?
Distribution and resistance.
What are arterioles used for?
Distribution and resistance.
What are capillaries used for?
Nutrient and waste exchange.
What are venules used for?
limited exchange and collection. Also some capacitance (blood storage).
What are Veins used for?
What is the Vena cava used for?
collection of blood sent into the heart.
What does it mean for a vascular compartment to be variably compliant?
Due to the capacity of the vascular system's smooth muscle cells to relax if exposed to sustained stretching forces the vessel can be enlarged if chronically overloaded with blood and this is a DELAYED COMPLIANCE.
Can delayed compliance also constrict vessels to increase pressure?
What is the major determinant of flow?
What causes the noise heard in a functional murmur?
due to the powerful ejections of blood from the left ventricle this can cause the blood to exceede reynolds number and become turbulent in the aortic arch.
Why is a functional murmur termed functional?
because it is of physciological and not anatomical origin.
What phase of heart contraction is the functional murmur heard?
What causes contact dermatitis? What will contact dermatitis cause?
Contact with an external agent. It causes a localized inflammation response in the integument.
What are the 2 types of contact dermatitis? Which one is more common?
1. Irritant (80%) 2. Allergic (20%)
What are the clinical features of contact dermatitis?
within minutes of exposure the skin becomes itchy, red and may blister.
How long will contact dermatitis last?
it disappears within a few days to weeks and blisters dry up.
What type of cells are the capillary beds made of?
Most blood vessles have _____ muscle around them in the form of a ______ _______.
Smooth, Tunica media.
What are the regulators of microvasculature (controlling the entry into capillaries)?
How is vascular smooth muscle innervated?
sympathetic branch of the autonomic nervous system.
Decreasing the radius of a blood vessel will do what to blood? This is aka?
decrease flow aka vasoconstriction
Increasing the radius of the blood vessels will do what to blood flow and it is aka?
It will increae flow and it is aka vasodilation.
What type of contractions will smooth muscle have?
slow sustained tonic contractions.
What is vascular smooth muscle like?
It is composed of small spindle shaped cells that lack the regulatory protein troponin. The actin and myosin are poorly organized. they can maintain a good slow level contracted state.
Is calcium needed for vascular smooth muscle to contract?
Yes. also needs atp.
What 3 ways can vascular smooth muscle tone be modified?
1. Mechanical stimulation 2. Electrical stimulation 3. Chemical stimulation
How is mechanical stimulation of vascular smooth muscle tone accomplished?
Rapid expansion of a vessel causes depolarization of the vascular smooth muscle (passive stretching lead to a contraction).
Why is the mechanical stimulation of vascular smooth muscle often described as autoregulation?
Because it stabilizes the flow.
Is the mechanical stimulation of vascular smooth muscle a slow or fast reaction?
If flow is increased in a vascular blood vessel what will mechanical stimulation do to it?
It will cause vasoconstriction and decrease the flow.
What happens to a vascular blood vessel with mechanical stimulation if the blood flow is decreased?
It causes vasodilation and increases flow.
How will mechanical stimulation of vascular blood vessels be effected by sustained force?
It may do the oppostie due to the slow delayed compliance.
What do endothelial cells of blood vessels do with increased shear stress?
They secrete nitric oxide.
What will nitric oxide do to vascular smooth muscle?
How will electrical stimulation of vascular smooth muscle work?
It will open voltage-dependent ca2+ channels and start an action potential in a neighboring smooth muscle cell.
How will the chemical stimulation of vascular smooth muscle cause a contraction or vasoconstriction?
The chemicals traveling from far or near will use the standard signal transduction pathway to increase intracellular ca2+ and elicit contraction.
Name the chemicals that are given that will cause vascular smooth muscle to contract?
norepineprine angiotensin II Vasopressin, Endothelin-1 Serotonin thromboxane a2
How will chemical stimulation cause vascular smooth muscle to relax or to vasodialate?
They cause a relaxation by inhibiting the contractile machinery.
Name the given chemicals that will chemicaly stimulate vascular blood vessels to vasodialate?
Nitric oxide prostacyclin local metabolites.
What will vascular smooth muscle need to respond to chemical stimulations?
Receptors or nothing will happen.
What are adrenergic receptors used to bind?
norepinephrine and epinephrine.
What specific adrenergic receptor is sensitive to norepinephrine? This receptor is released from what?This reaction will cause what?
alpha1 receptor axons of sympathetic fibers vasoconstriction
What will Beta2 receptors cause?
What is an alpha blockade?
it uses alpha adrenergic blockers that are specific to alpha1 receptors to manage blood pressure in hypertensive patients this causes widespread vasodilation.
What will endothelin-1 receptors and Angiotensin-2 receptors cause to happen when they get the proper chemical stimulant?
They cause vasoconstriction.
What chemical is cholinergic receptors sensitive to? What will this cause.?
acetylcholine causes vasodilation
Are the same receptors in different areas of the body equally receptive?
no cerebral vascular smooth muscle is not nearly as responsive as GI vascular smooth muscle.
Nitric oxide is secreted due to shear forces of the arterial walls and how else?
It is released by endothelial cells after shear force is excerted on them and when endothelial cells have hormones and paracrine compounds stiumlate them. Both ways nitric oxide is released and causes vasodiliation.
How will nitric oxide cause vasodiliation?
It acts as a paracrine agent and causes intracellular levels of ca2+ to drop.
How will prostacyclin specifically effect vascular smooth muscles?
When signaled to do so by blood borne agents endothelial cells will release prostacyclin(a hormone and paracrine agent) and this causes vasodilation working through the G-protein singal transduction system.
What is a vascular spasm?
A rapid and profound vasoconstriciton with endothelial injury. When the endothlia is damaged it loses it's ability to secrete nitric oxide and loses its ability to balance diameter and the diameter shifts towards vasoconstriction.
What is the purpose of nitroglycerin & amyl nitrite when talking about vascular vessels?
It is an organic nitrate drug that can cause profound vasodilation. They just serve as an extra source of nitric oxide. Used with chest pain to allow vasodilation and let more blood flow to the heart.
What will the production of H+ and co2 made in tissue cause to happen in vascular vessles?
It inhibits the ability of vascular smooth muscle to contract and this induces a local vasodilation.
What are the 2 broad sources of chemical agents that effect vascular smooth muscle?
Intrinsic- local control Extrinsic- Humoral or nervous control.
Generally intrinsic control causes what? Generally extrinsic control causes what?
Intrinsic- vasodilation Extrinsic- Vasoconstriction
Which control intrinsic or extrinsic is more rapid and more important?
Intrinsic control usually comes from where?
Local paracrine agents from tissue.
When is the extrinsic control most important?
During critical periods.
What makes extrinsic control more potent?
Receptors Non essential tissues can have lots of receptors and be very vasoconstricted Under these circumstances extrinsic control cna overide intrinsic control.
Increased metabolism will do what to blood flow?
Decreased metabolism will do what to blood flow?
Why will increased metabolism increase blood flow?
due to the production of tissue metabolites (waste) that needs to be removed. NOT due to oxygen demand.
What is active hyperemia?
Increased blood flow from activity/metablism.
With increased blood flow the tissue produces a reddening color called what?
What is the major metabolic waste from tissues or cells?
H+ This comes from co2 + h2o--> h2co3- + H+ so co2 is part of this process and is also a metablic waste.
Besides H+ and Co2 what are some metabolic waste from tissues or cells?
Adenosine Potassium ion Lactic acid
What is the primary control for setting tissue blood flow in the body and what is it like?
Local control and it is automatic and tissue centered.
Since all tissues are crying out I want blood, but they all cant get what they want and some become deprived of nutrients and this is called?
When tissues are ischemic they are not getting enough blood and are deprived of oxygen and accumulate deoxygenated blood and get a blue color called?
Ischemia will produce what in affected tissues?
Since automatic control of blood flow could lead to chaos how will body wide order be controled?
What is bradykinin?
Damaged blood that causes vasodilation.
What type of chemical stimulant is histamine on vascular vessels? Where will it come from?
vasodilation comes from mast cells.
What is reactive hyperemia?
After a tissue is ischemic it has had no blood for a while and when blood is restored blood will flow there in a massive way that nearly matches the amount of blood that would have been delivered there the whole time it is blocked. Lots of blood will flow here until complete restoration of oxygen levels and all metabolites are gone.
Extrinsic control of the vascular sytem involves what?
The Central nervous system.
What type of axons innervate vascular smooth muscle?
where do the autonomic axons come from that innervate the vascular smooth muscle?
The spinal sympathetic chain.
the axons that terminate on vascular smooth muscle will secrete what? what will it do?
They Secrete norepinephrine that lands on alpha1 adrenergic receptors and cause vasoconstriction.
what is vasomotor tone?
A steady low-level activity of autonomic nerves that produces a background tone(a vasoconstiction tone) in the peripheral vasculature.
How will most systemic blood vessels get innervated?
By spinal sympathetic chain axons NOT paraysmpathetic innervation.
Overall what effect will the autonomic nervous system have on blood vessels, blood pressure, and blood volume?
Blood vessels will vasoconstrict Blood pressure will rise Blood volume available to be used will increase, but actual volume remains the same.
Name another type of extrinsic control of vasculature besides autonomic control?
where is the adrenal medulla found at and what will it do?
it is located above the kidneys. It is an extrinsic control of vasculature.
what will the adrenal medulla release and what will this do?
Epinephrine 80% and norepinephrine 20% This will cause vasoconstriction.
What will cause the adrenal medulla to release it's hormones (epinephrine and norepinephrine)?
Sympathetic nervous system axons that originally are in the medulla of the brain.
After the adrenal medulla relase epinephrine and norepinephrine where will it go?
It goes to alpha1 adrenergic receptors on vascular smooth muscle and this causes vasoconstriction.
When wil the adrenal medulla release it's hormones?
After sympathetic nervous system tells it to, and this is probably a steady background release rate.
How fast and how powerful are the hormones released by the adrenal medulla on vasculature smooth muscle?
It is powerful, but slow.
How is the kidney involved in extrinsic control of the vascular smooth muscle?
The renal cortex relases renin.
What will renin released from the renal cortex do?
It causes the formation of angiotensin II.
What will angiotensin II do?
It will go to angiotensin II receptors on vascular smooth muscle and causes endothelin-1 production to result in vasoconstriction.
When will the renal cortex release renin?
This is probably a steady background release rate .
How powerful and how quick is the effect of renin on the vascular smooth muscle?
It is powerful and slow.
What will the posterior pituitary gland do to effect vascular smooth muscle?
It will release vasopressin.
What will vasopressin do?
It effects blood vessels and renal collecting ducts.
Where will vasopressin go?
It goes to vasopressin receptors at many locations.
How will vasopressin effect vascular smooth muscle and how will it effect collecting ducts of the kidneys?
It will cause vasoconstricion of the vascular smooth muscle. It will cause more aquaporins in cells and this results in retention of water.
When will the posterior pituitary gland release vasopressin?
This is also a steady background release rate.
How powerful and how fast are the effects of vasopressin?
Powerful and slow.
How will hormones effect the extrinsic control of blood vessels, blood pressure, and available blood volume?
Blood vessels will vasoconstrict Blood pressure will go up available blood volume will increase.
What is contact dermatitis?
Dermal inflammation due to exposure to an irritant or allergent.
How will harsh chemicals cause irritation?
They cause local mast cell degranulatoin.
How will allergents cause contact dermatitis?
Langerhans cells of the epidermis alert the rest of the immune system and the sensitization process begins.
In all cases of contact dermatitis what is released?
What will histamine do to the arteriols and the capillaries?
It will promote vasodilation and capillaries will be leaky.
How long after contact to irritant in contact dermatitis until the skin becomes itchy and red? Why?
minutes, because histamine must change vessels and it takes a short while to leak enough fluid out to accumulate faster than it can be removed.
Congestive heart failure is a condition wherein what happens?
The heart fails to adequately pump blood.
How long will it usually take to develop congestive heart failure?
It is a gradual disease.
What are 2 subforms of congestive heart failure?
systolic and diastolic.
How common is congestive heart failure?
Common in older people. over 50 -1% over 75 -5%
Name 3 clinical findings of congestive heart failure?
1. Dyspnea= A breathing Hunger. 2. peripheral edema= swelling in peripheral 3. fatigue
What are 2 laboratory findings in congestive heart failure?
1. Enlarged heart 2. Low ejection fraction
what are cardiac muscle cells like?
Small striated muscle cells anchored by intercalated disks.
What will intercalated disks act as?
A point of low electrical resistance.
What is functional syncytium?
Allowing the impulse/ action potential to propagate from cell to cell.
The heart is a demanding tissue that requires what?
An extensive capillary density within its endomysium to deliver a steady supply of oxygen.
What will happen to the cardiac muscle cells with even a slight reduction of oxygen?
Ishcemia, and cells will not be able to maintain its polarized state and will reach its action potential causing it to fire this will cause other cells to fire due to syncytium. Then everything fires out of control.
What happens to heart cells when they die?
They can't regenerate.
Can cardiac cells grow?
They can't regenerate or reproduce, but they can hypertrophy.
What are purkinje cells of the heart?
Special cells that have abandoned much of their myofiberillar appartus for rapid impulse conduction/propagation. They help get the depolarization stimulus everywhere at the right time.
What is the action potential of cariac cells like?
The action potential is very long (not the contraction, but the action potential)
When will a contraction of cardiac muscle occur in relationship to the action potential?
It comes shortly after depolarization not right away.
What are the 3 phases of cardiac muscle action potential?
1. Depolarization 2. Plateau 3. Repolarization.
How will cardiac muscle depolarization occur?
Rapid influx of na+ voltage gates that open Ca2+ channels.
What is the caridac muscle like during the plateau of an action potential?
cells are resistant to stimulation and can't contract called ABSOLUTE REFRACTORY PERIOD.
What is the repolarization phase of the cardiac muscle action potential like?
K+ is relocated to the interior and the cells are in a RELATIVE REFRACTORY PERIOD.
what is the end ot the relative refractory period called? And what is it like.
Supranormal excitability period. Where stimulation easily causes another depolarization.
What is digoxin?
A poison from foxglove leaves that binds sodium/potassium exchange pumps in cardiac muscles and inhibits them this leads to intracellular levels of na2+ increasing and the ca2+ levels will increase and the heart will have a stronger beat and can cause congestive heart failure.
What will happen to a cardiac muscle cell when the cell is lengthened during the relaxation?
It tends to produce a stronger contraction in the next cycle.
What type of stess is the heart responsive to?
What will chronic stress do to the heart?
Cause it to work harder and this leads to very serious hypertrophy.
Is the action potential of all cardiac muscle cells the same?
No it is variable.
What is the time like that sino-atrial nodal cardiac muscle cells spend depolarizing and repolarizing?
THey are slow to depolarize(send contraction) and quick to repolarize(get ready to contract).
What will regular cardiac muscle cells do/show before repolarization?
They have a broad plateau phase.
Why will different cardiac muscle cells have variable action potentials?
Due to different inoic gating systems.
What will the plateua phase before repolarization do in cardiac muscle?
It sets limits on the number of beats per minute.
What is auto-rhythmicity?
Spontaneous action potentials (cardiac cells can spontaneously create action potentials)
How will cardiac muscle cells create auto-rhythmicity?
They have naturally leaky membranes that allow ions to move intracellularly.
What type of cardiac muscle cells have the fastest cycle of polariztion and repolarization?
SA node (sino-atrial node). Even though the action potential isn't as fast in the depolarization phase.
Cardiac muscle cells are complexly covered with what? And this will lead to what?
Receptors. That make cells sensitive to hormones and neurotransmitters.
Name the 2 groups of receptors found on cardiac muscle cells?
1. Adrenergic receptors 2. Cholinergic receptors
What is the primary type of adrenergic receptor found on cardiac muscle cells? What are these receptors sensitive to and where will this come from?
Beta1 receptors They are sensitive to norepinephrine released from the axons of the sympathetic fibers.
What wil norepinephrine do to cardiac muscle cells once it comes in contact with the beta1 receptors(from the adrenergic receptor group)?
Increase the excitability and strength and rate of contractions by hypo-polarizing the plasma membrane of the cell.
What is the major cholinergic receptor and what is it sensitive to and where will it come from?
Ach "muscarinic" receptors sensitive to acetylcholine. Acetylcholine is released from parasympathetic fiber axons.
What will acetylcholine released from parasympathetic fiber axons do to cardiac muscle cells when it contacts cholinergic receptors(from the cholinergic receptors)?
Decrease the excitability and strenght and rate of contraction by hyperpolarizing the membranes.
What are the main pumps of the heart?
What type of pump are the atria?
What is the valve of the heart that is between the right atrium and the right ventricle?
Right Atrioventricular valve aka Tricuspid.
What is the name of the valve between the left atrium and left ventricle?
Left atrioventricular valve aka mitral.
What are the right and left valves that leave the venticles?
Right and left semilunar valves Right aka pulmonic left aka aortic
What is the shape of the right ventricle?
Crescentic or "c" shaped.
What will the high pressure pump aka the left ventricle look like?
What are the 2 circulatory systems of blood flow?
1. Systemic circulation= extensive body wide. 2. Pulmonary circulation= small and goes to lungs.
What are the names for the contraction and relaxation periods of the heart?
Contraction= systole relaxation= diastole
What is the cardiac cycle?
The full action of the heart per beat.
What are the 6 parts to the cardiac cycle?
1. Ventricular pressure 2. Aortic pressure 3. Ventricular volume 4. Electrocardiogram 5. Phonocardiogram 6. Atrial pressure.
How will blood flow into the ventricles at rest?
75% comes from normal blood flow through the veins. 25% is done by systolic atrial contractions
Since only 25% of blood in ventricles comes from atrial contractions what is the purpose of the atrium?
Maximizes the efficiency of each ventricluar beat.
What is isovolumetric relaxation?
A very brief period of no filling of the ventricle during diastole.
What is rapid inflow?
It is 1/3 of the time of blood inflowing and filling the ventricles where 75% of the blood is passively brought in.
What is diastasis?
1/3 of the time for filling the ventricles where minimal filling happens.
What is the atrial systole phase?
1/3 of the time for filling the ventricles where the atria actively fill the last 25% of the ventricals.
What are the valves doing during isovolumetric contraction?
The valves are closed.
When will the isovolumetric contraction take place?
During the systole phase at the begining.
What happens after isovolumetric contractions of the systole phase?
Ejection of blood.
What is the end-diastolic volume measuring and what is the number?
Volume of blood in the ventricle at the end of diastolic phase. about 130ml.
What is end-systolic volume measuring and what is the number?
It measures the volume of blood in the ventricle at the end of systole about 60ml
What is the stroke volume measuring and what is the normal number.
It is the volume of blood that the heart ejected so take the end-diastolic volume and minus the end-systolic volume and we get the stroke volume normal is about 70ml.
What will the ejection fraction measure and what is the normal number and when will it be a problem?
stroke volume divided by end-diastolic volume which is a percentage of blood volume ejected and should normaly be 50% problems if it is less than 40%.
What part of the electrocardiogram is systole slightly preceded by?
What will the QRS complex do?
It causes the Ventricles to contract. Then ejection happens.
What is the T wave?
The part of the electrocardiogram where the ventricle cells repolarized near the end of ejection.
What is a P wave?
A P wave causes atrial systolic filling not just blood gussing into the ventricles.
What happens to ventricular pressure at the onset of systole and why?
It skyrockets because of the imediate closure of the mitral valve.
What is the period of isovolumetric contraction?
The volume of blood will stay the same because the mitral and aortic valves are both closed and ventricular pressure increases because no blood can get out and the ventricle is contracting.
When will the peroid of ejection begin?
As the pressure inside the ventricle exceeds the pressure in the aorta then the aortic valve will open and ejection happens.
What happens during the period of ejection?
The aortic and ventricular pressure both increase until they reach a peak and then they both start to drop.
What happens when the aortic and ventricular pressures fall during the period of ejection?
The Ventricular pressure will fall below the aortic and this will cause the aortic valve to close.
What happens after the aortic valve closes?
Isovolumetric relazation because both mitral and aortic valves are closed this allows aortic pressure to remain almost the same and ventricular pressure to fall off to zero.
What is the ventricular pressure like during filling of the ventricle?
It remains at essentialy zero and rises briefly during atrial systol filling.
What is the normal systolic pressure and what is it?
It is about 120 mm Hg and it is the peak aortic pressure derived from systole.
What is diastolic pressure and what is the normal pressure?
It is the lowest aortic pressure found at the end of diastole and it is normaly about 80 mm Hg
What could make the Diastolic pressure lower?
Lower heart rates because the aortic pressure would have more time to drop.
What is the Dicrotic notch?
It is a small increase in aortic pressure due to elastic recoil following the aortic valve closure.
What causes heart noise?
Valve action most likely valves closing.
What causes S1 and S2 and what sounds will they make?
S1- Closure of the AV valve and makes the Lub sound S2- Closure of the semilunar valves makes a dub sound
What is heart auscultation?
Listening to the heart.
What 2 things can cause valvular abnormalities in general?
1. Stenosis- difficulty pushing blood through. 2. Insufficiency- valve fails to prevent backflow.
What is Aortic Stenosis? What will it cause and it is known as what?
Difficulty pushing blood through the aortic valve. This creates a loud murmur heard during left ventricular ejection. Can be heard by standing by someone and is called a Thrill.
What is aortic insufficiency?
The aortic valve fails to prevent backflow into left ventricle a murmur is heard during diastole.
What is mitral stenosis?
Difficulty pushing blood through the mitral valve creates a murmur during second half of diastole.
What is mitral insufficiency?
Mitral valve fails to prevent blood to backflow into the left atrium and creates a murmur heard throughout systole.
What is chamber dilation?
When the heart has vascular abnormalities it works harder to maintain the net stroke volume and this causes hypertrophy and can overload the heart and this leads to chamber dilation and failure.
What is cardiac output?
Combine the stroke volume(volume of blood pumped inot aortic arch each beat) and multiply it by the heart rate (beats per min.) This gives us the volume of blood pumped into the aortic arch per minute.
What is the normal cardiac output?
Cardiac input can rise from the normal 5L/min to what?
Up to 30L/min
What are 2 basic regulations of cardiac output?
1. Intrinsic autoregulation 2. Reflex (extrinsic) control
What is the mechanism for intrinsic autoregulation of cardiac output?
Frank-starling mechanism or Law of the heart.
What is Frank-starling mechanism or law of the heart?
When Diastolic filing goes up the chamber is stretched and this will increase the end diastolic volume this will increase the strength of contraction and this decreases the end systolic volume and this will increase the stroke volume.
According to intrinsic autoregulation of cardiac output what happens when venous return to the heart is increased?
Increase cardiac output in other words put more blood in more comes out.
since the heart pumps all the blood that comes to it, it will be described as what type of pump?
A permissive pump.
What is most important in regulating cardiac output?
The peripheral factors that affect returining blood flow.
What is preload?
An incoming force that creats a tensile load on the chamber muscle prior to contraction
What are the limits to increasing cardiac output with just the intrinsic autoregulation? What happens after the top?
it tops out at about 15 L/min. Performance will decline.
What else will happen when the right atrium stretches besides frank-starling mechanism?
The SA node is stretched and this will increase rate of discharge (heart rate increaes).
What is afterload?
The tensile load the heart or a muscle must exert itself.
Will blood pressure affect cardiac output?
not normally only when aterial pressure becomes so high that it is too dificult to pump against.
How is reflex (extrinsic) control of cardiac output done? How much can it increase the cardiac output?
Mostly by nerves of the autonomic nervous system. Can increae up to 30 L/Min.
What part of the heart will sympathetic and the parasympathetic innervations mainly go to?
Sympathetic- The Ventricles. Parasympathetic- The Nodal tissues.
what nerve supplies parasympathetic innervation for the heart?
Vagus or X cranial nerve.
What will the sympathetic nervous system activate the body to do?
Cope with stress or situations of heightened response.
What will the parasympathetic nervous system do for the body?
attends to digestive, elimination and glandular functions.
What will sympathetic and parasympathetic neurons secrete?
Sympathetic- norepinephrine parasympathetic- acetylcholine.
What will the autonomic nervous system mostly do to the cardiovascular system?
Readiness regulator. Or sympathetic
In what 3 ways will nerves effect cardiac muscle?
1. Dromotropic effect- conduction speed 2. Chronotropic effect- rate of contraction 3. Inotropic effect- strength of contraction
What receptors will work with norepinephrine and where are they found at?
Beta 1 adrenergic receptors and they are found on cardiac myocytes.
What happens to cardiac muscle cells when their beta1 adrenergic receptors bind with norepinephrine?
This will increase dromotropism, chronotropism, and inotropism This increases the heart rate to about 200 beats/min. And this increases stroke volume to 100%
What else will norepinephrine do to cardiac muscle cells?
Renders them receptive to circulating epinephrine that comes from adrenal glands.
When we exercise how will sypmathetic nervs effect stroke volume and heart rate?
They both increase, but stroke volume is increased early and heart rate steadily increases with work.
What is the maximum efficiency of the heart?
140-160 beats per minute.
What is tachycardia?
a heart rate greater than or equal to 100 beats/min.
Is Tachycardia normal?
If not at rest then it can be, but at rest this would be a problem.
If sympathetic nervous system stops what effect will this have on the heart? Will this ever happen if so when?
It can reduce the cardiac output by 25%. It should never happen because there is a background level of sympathetic activity from the brain.
What will Beta2 receptors found on cardiac vasculature do when sympathetically stimulated?
What is beta blockade?
Drugs called beta blockers limit the cardiac output like a governor on a car by blocking the beta 1 adrenergic recpetors from receiving their signals from the sympathetics.
When cardiac muscles have the acetylcholine receptors they will respond to what?
Acetylcholine from the parasympathetic system.
Where will most acetylcholine receptors be found at?
On the SA and AV nodal cells.
What will happen to the cardiac cells stimulated by acetylcholine through acetylcholine receptors?
A negative dromotropism, chronotropism, and inotropism Leading to a decreased heart rate at about 30-40 beats/min. And a decreaed stroke volume of 25%.
What happens to the parasympathetics of the heart when the heart receives sympathetic innervation?
It is attenuated, and vice versa.
What is bradycardia?
a heart rate at or below 60 beats per minute.
Is bradycardia normal?
In healthy people it can be and abnormal in other conditions.
Reflex control of the heart generally enhances what?
What type of control is rapid and even anticipatory?
What happens when preload of the heart becomes too great?
The heart enters a state of decompensation and decreased ejection and increases venous return. This leads to congestive heart failure.
What is congestive heart failure?
An inability of the heart to produce an adequate cardiac output.
Congestive heart failur is also considered to be a form of what?
A decompenstaed heart.
What type of condition is congestive heart failure?
What are the physciological findings of congestive heart failure?
Failure of the law of the heart. More blood in does not give us more blood out anymore.
Where will blood backup into with congestive heart failure?
commonly in lungs and periphery like the ankels, and feet.
People with congenstive heart failure get fatigued due to what?
decreased cardioac output.
what is CAD?
Coronary artery disease.
What is CAD a major source for?
Congestive heart failure.
What is A-V heart block due to?
An arrhythmia due to a blockage in the electrical conduction system.
What are the subtypes of A-V heart block?
1st degree- mild interruptions, second degree- moderate interruption, third degree- severe interruption/disruption.
How common are the different types of A-V heart block, and what symptoms will they have?
First degree is common and symptom free. Second degree is less common and causes irregular heart beats, thrid degree is a complete disruption and results in cardiac output problems.
What are the laboratory findings for A-V heart block?
How will all heart cell contractions originate?
With a myocyte action potential.
Since each cardiac cell has its own unique action potential that allows them to spontaneously depolarize and impulse and then propagate this to the neighboring cells how will the heart not get out of control?
It has a wiring system called the conduction system.
What makes cardiac conduction system cells different from cardiac muscle cells?
They lost ability to contract a lot, but can conduct depolarization impulses rapidly.
What region of cardiac muscle cells is fastest to recycle (have a short refractory period)?
Because the SA node is fastest at recycling what will it be able to do?
It usually leads the pack and is known as the pacemaker because it produces a sinus rhythm.
What else besides the SA node can become the pacemaker of the heart?
Any patch of cardiac tissue that fires faster than the SA node.
Why will cardiac muscle cells usually not mis-fire (impulsing before the SA node)?
They have a longer refractory period.
What happens when the SA node is stretched?
It tends to fire faster and increase the heart rate.
Will contraction impulses spread faster across the atria or ventricles?
Faster across the atria.
What will the fibrous skeleton do with the electrical impulses?
It will prevent it from leaking into ventricles except at the AV node.
What will the AV node do to the impulse propagation?
It holds it up for 1/10th of a second.
Why is the impulse delayed at the av nodes?
it allows the atria to have enough time to physically contract before ventricles contract allows them to be topped off.
Besides creating a pause in the impulse propagation what will the AV node do to the electrical impulse?
It wont allow it to go backwards a one way street.
What will the parasympathetic and sympathetic stimulation do to the SA and AV nodes?
Paraympathetic- hyperpolarizes the SA and AV nodes, Sympathetic- hypo-polarizes the nodes.
What is the electrocardiogram?
a display from a supersensitive voltmeter called and electrocadiograph.
What will an electrocardiogram represent?
a collective voltage of thousands of cells.
What will the ECG's P wave correspond to?
What will the ECG's QRS complex correspond to?
What will the ECG's T wave correspond to?
What will the Q wave from the QRS complex correspond to?
Depolarization of the emerging bundle of AV nodes.
What will ther R wave from the QRS complex correspond to?
Rapid depolarizatoin of the ventricles.
What will the S wave from the QRS complex correspond to?
rapid reversal of the impulse directoin at apex and now towards the base.
The QRS complex happens real fast and what will it mean if it is not smooth or slow?
indication of a serious problem in the ventricles.
What is the flat line on the ECG called?
What is a combination of waves or wave segment on an ECG?
What is the PR segment of an ECG due to?
AV nodal slowdown.
What is the ST segment of an ECG due to?
IT is during the absoluted refractory period.
Why would the ST segment be examined?
To see if there is serious problems in the muscle cells of the ventricles.
How did the pr segment get its name?
Beacuse this happens when the Q wave is absent.
What is the PR segment showing?
A long delay in the AV node that indicate some sort of electrical system blockage between atria and ventricals.
What is an interesting use of an ECG?
To calculate the direction of specific voltage directions.
What is it called when we plot the direction of electrical current flows in the heart?
How can one synthesize a mean QRS vector? This is AKA?
By summating the QRS voltage. AKA electrical axis of the ventricles.
What is the average location of the electrical impulse?
60 degrees going from the subjects left arm.
What will changes in the vector of the electrial axis of the ventricles show?
Changes/ damage to the ventricles.
What is the normal range of the QRS vector? What will a shift out of this range be termed?
-10 degrees to 100 degrees. known as axis deviation
What is an ECG Lead?
The specific location of the volt-meter electrodes on the subject not the electrodes themselves.
Why are there so many different ECG leads?
So we can get different views of the heart.
What is the key purpose of the conduction system?
TO create a synchrony.
What is asnchronous contractions called?
What are 4 different ways in which an arrhythmia can occur?
1. Abnormal rhythmicity of the pacemaker itself. 2. Blocks in the conducting system. 3. Abnormal impulse pathways. 4. Spontaneous generation of spurious impulses in the heart.
What 2 things can cause tachycardia?
1. Increased body temperature. 2. Sympathetic stimulaton of the heart.
How many beats per minute will the heart increase with a body temperature increase of 1 degree F? And what is the limit on this?
10 BPM increase per 1 degree F and this only goes up to 105 Degrees F.
What 3 things will make the sympathetic system increase the Heart beat?
1. Exercise. 2. Reflex acton due to decreased Cardiac output. 3. Thoughts= anxiety, excitement.
Bradycardia is usually due to what?
When will bradycardia be abnormal?
When we have a decreased resting heart rate due to parasympathetic stimulation that is a result of pressure sensors in the neck that have become compressed.
What is sinus arrhythmia due to? What will it cause?
Ventilation when we inhale it increases the heart rate and when we exhale it decreases heart rate. It causes chages in sympathetic and parasympathetic signals.
What is a atrioventricular block?
a disturbance in the conduction impulses from the atria to the Ventricles.
An atrioventricular block is often due to what?
Ishemia of the AV node.
Name 3 subtypes of atrioventricular block and what they are like?
1st degree- minor lengthening of the PR interval. 2nd degree- a serious lengthening of the PR interval, and occasionaly missing a beat in the ventricles. 3rd degree- Ventricular escape
What is an intraventricular block?
The same as an artrioventricular block, but in the purkinje system which gives an abnormal QRS interval.
What is ectopic mean?
Out of place.
What is ectopic foci?
An electrical event out of proper location.
What are 2 types of ectopic foci?
1. Premature contraction. 2. Fibrillation
A premature contraction is often termed as what?
An extrasystole or premature beat or ectopic beat.
What are 2 types of premature contractions and how serious are they?
1. Atria- harmless. 2. Ventricle- can be deadly.
What causes a premature contracion?
hyper-excitablity of myocardial tissue and it will depolarize at the wrong time.
What are 2 ways myocardial tissues can depolarize at the wrong time?
1. Over-use of stimulants and lack of sleep. 2. Local ischemia.
How will local ischemia cause premature contractions?
It will not have the oxygen to make the atp that is needed to run pumps and maintain the membrane potential.
What can premature contractions lead to?
an abnormal impulse pathway like a electrical chaos.
What is Fibrillation?
When electrical chaos will have impulses spread and split and re-enter areas.
What will atria and ventricular fibrillation lead to?
Atria- tolerable, but not good for the atria. Ventricles- Deadly within 2-3 minutes.
Why will ventricular fibrillation be deadly within 2-3 minutes?
It will give no true contraction so no ejection of blood.
Name 2 ways fibrillation starts?
1. Electrical shock. 2. Myocardial ischemia (most common cause).
What is Impulse re-entery mechanism?
impulse goes around and the cells are past the refractory period when the impulse gets back and so they impulse again and this can get out of control.
What will cause impulse re-entery?
slow impulse conduction, or long impulse paths.
What is defibrillation?
A technique to interrupt ventricular fibrillation by applying a large electrical shock, and after the full depolarization the hope is that the SA node will impulse first and bring the heart out of fibrillation.
When is fibrillation done intentionaly?
During surgeries to keep the heart still.
How long after ventricular fibrilation will defibrillation need to occur to stop fibrillation?
1 minute or heart is too weak unless cpr has been done to help minimize damage to the heart prior to defibrillation.
What is A-V heart block?
an arrhytmia due to a blockage in the electrical system of the heart.
What are 2 causes of A-V heart block?
1. Coronary artery disease. 2. Inflammation of nodal tissue.
What are the treatments for A-V heart block?
mediaction for mild cases and a pacemaker for severe cases.
Renal artery stenosis is a disorder of what?
Vascular occlusion in the kidneys.
What are 2 clinicl features of renal artery stenosis?
1. Hypertension. 2. Abdominal bruit (a noise).
What type of people are associated with renal artery stenosis?
Obesity, tobacco, retinopathy (disease of the retina)
People with renal artery stenosis when scaned show what?
A narrowing of the renal artery that decreases flow into kidneys by 70 % or higher.
What happens to a kidney that has a decreased blood flow from renal artery stenosis?
What is one of the most important negative feedback loops in the entire body?
The control of blood pressure.
What is it called when we compress a fluid in a finite container?
Blood pressure is high in the left ventricle and in the aorta and the large vessels and the pressure does what?
What happens to blood pressure as it gets into the arterioles?
It starts to dampen out so it wont pulsate as much.
What is pulse pressure?
Take systolic blood pressure and subtract the diastolic blood pressure from it. This is usually 40 mm hg
when will pulsatile pressure be gone normaly?
In the capillaries.
What helps arteries dampen the pulsatile pressure?
The elastin in the large vessels.
When we measure blood pressure in clinics what type of blood pressure are we measuring?
Systemic arterial blood pressure.
What is the average blood pressure in the larger arteries?
100 mm Hg
What is augmentation?
it is due to pulse reflection in the arterial tree causing a summation of pulse waves.
What may augmentation correlate to?
An aneurysm in large arteries