Exam 3 Flashcards
What carries oxygen poor blood to the lungs and back to the heart?
Pulmonary ciruit
What carries blood from the heart to the rest of the body?
Systemic circuit
What is the right AV called?
Tricuspid
What is the left AV called?
Bicuspid
The aortic valve is also called?
Semilunar valve
Explain cardiac action potential?
1) Na+ enters (depolarization)
2) Transient K+ exit
3) Ca2+ enters and K+ exits (plateau phase)
-this doesn’t happen in skeletal muscle
4) K+ exits (re-polarization)
Explain the step in heart beat coordination?
-Pacemaker cells (generate own AP)
1) SA node Pacemaker (right atrium) depolarization of both atria
3) AV node
4) Bundle of his
5) Purkinje fibers
What occurs during atrial excitation? and what occurs on EKG
1) SA node and AV node excite
2) *** P-wave (atrial depolarization)
What occurs during ventricular excitation/ depolarization? and what occurs on EKG
1) Ventricles contract
2) QRS wave
***when this occurs it masks atrial re-polarization/ relaxation
What occurs during Ventricular re-polarization (relaxation)? and what occurs on EKG
1) Ventricles relax
2) T wave
What is the process of producing an electrocardiogram (ECG or EKG), a recording of the electrical activity of the heart using electrodes placed on the skin, represented as a graph?
Electrocadiography
What is a record or graph of a person’s heartbeat produced by electrocardiography?
Electrocardiogram (ECG or EKG)
What requires the temporary threading of a thin, flexible tube called a catheter through an artery or vein into the heart?
Cardiac angiography
What is a noninvasive technique that uses ultrasound?
Echocardiography
this is a conducting cell that takes over excitation in the conduction system?
-If the SA node is damaged the AV node can take over. This is still adequate for normal circulation.
Ectopic pacemaker
What are uncoordinated atrial and ventricular contractions caused by a defect in the conduction system?
Arrhythmias
What is a rapid and irregular (usually out of phase) where the SA node is no longer controlling heart rate:
There are 2 types?
1) Fibrillation
-Atrial fibrillation
-Ventricle Fibrillation
(these are Arrhythmias)
What is the application of an electrical stimulus to shock the heart back into a normal SA rhythm? For chronic conditions _____________ can be implanted. This is a device that delivers the electrical stimulus rather than the SA node.
1) Defibrillation
2) Pacemaker
(heart sounds)
Normal open valve
Laminar flow= quiet
(heart sounds)
Stenotic Valve
Narrow valve = Turbulent flow = murmur
(heart sounds)
Normal closed valve
No flow = quiet
(heart sounds)
Insufficient valve
Leaky valve = turbulent backflow = murmur
_______ is 90% water and carries electrolytes and nutrients (glucose, amino acids, vitamins) as well as wastes (urea, bilirubin, creatine), gases (O2 and CO2), and hormones
Plasma
__________ is plasma with fibrinogen and other proteins involved in clotting removed.
Serum
Explain Erythrocyte (or RBC) Formation
1) Kidney secretes EPO in Blood
2) EPO enters bone marrow causing (Erythropoiesis) forming erythrocytes
3) Erythrocytes travel through the blood to the spleen
4) Spleen breaks down Erythrocytes into iron and Brilirubin
5) Bilirubin enters liver and is converted into bile
6) Bile is excreted by the kidney into the urine
If there is an increase in the breakdown of Erythrocyte by the spleen this causes an increases in brilirubin which increases bile production by the liver which leads to which disease?
Jaundice/ Splenomegaly
What happens to patients who kidney have failed?
they have to little erythropoietin and need to have synthetic forms administered to maintain normal RBC count
What also enhances RBC production by increasing EPO production?
Testosterone
What is defined as a decrease in the oxygen-carrying capacity of blood?
Anemia
What are cytoplasmic fragments derived from megakaryocytes, these are cell fragments have NO ORGANELLES, but they do have GRANULES and are important in blood clotting?
Platelets also known as thrombocytes
the Granules contain secretory products:
1) ADP
2) Serotonin
3) epinephrine
What is the physiological mechanisms that stop bleeding called?
Hemostasis
What are the 3 steps in hemostasis?
1) Vasular spasm
2) Formation of platelet plug
3) Blood coagulation (clotting)
After hemostasis intact blood vessel then secretes NITRIC OXIDE (NO) and PROSTACYCLIN which causes respective:
1) Vasodilation
2) Inhibit platelet aggregation
What are anticoagulants?
Prevent clot formation
What are some anticoagulants?
1) Aspirin (inhibit prostaglandins)
2) Heparin (inhibits thrombin activity)
3) Citrate (inhibits clotting factors)
What are phagocytes, and their production and release from the bone marrow increase during infection
Neutrophils
What fights off invasions by eukaryotic parasites; they either release toxic chemicals that kill parasites, or they phagocytize parasites
Eosinophils
What secretes anti-clotting factors called heparin at the site of infection, which helps the circulation flush out the infected site; they also secrete histamine to attract infection-fighting cells and proteins to the site?
Basophils
What are phagocytes that circulate in the blood for a short time, after which they migrate into tissues and organs and develop into macrophages?
Monocytes
What are large phagocytes capable of engulfing viruses and bacteria?
Macrophages
What are composed of T- and B- lymphocytes that protect against specific pathogens?
Lymphocytes
What is the cardiac cycle?
1) Diastole
2) Systole
What is the relaxation phase of the cardiac cycle?
Diastole
What is the contraction phase of the cardiac cycle?
Systole
What is the filling phase of the cardiac cycle?
Diastole
What is the pumping phase of the cardiac cycle?
Systole
What is the volume of blood in one ventricle at the end of diastole called?
End diastolic volume (EDV)
What is the volume of blood in one ventricle at the end of systole called?
End systolic volume (ESV)
What is the volume of blood ejected from one ventricle in each cycle called?
Stroke volume
What is the stroke volume equation?
SV= EDV - ESV
What happens to the SV if EDV increases?
SV increases
What happens to the SV if ESV increases?
SV decreases
What is the ability of the VENTRICLES to STRETCH and fill with blood?
Pre-load
What is the ability of the VENTRICLE TO EMPTY (has to push against aortic pressure)?
After-load
What is considered the venous return?
a) Pre-load
b) After-load
a) pre-load
what is the amount of blood pumped out of each ventricle in one minute called?
Cardiac Output
How do you calculate cardiac output?
SV*HR=CO
What causes an increase in heart rate?
Positive chronotropic factors (Norepinephrine = Sympathetic nervous system)
What causes heart rate to decrease?
Negative chronotropic factors (Acetylcholine = parasympathetic nervous system)
What states that the critical factor controlling stroke volume is PRELOAD?
-The most important factor in causing stretch is the amount of blood in the ventricles. The amount of blood in the ventricles is controlled by venous return.
Starlings law
this is defined as the ratio of stroke volume to end-diastolic volume (SV/EDV)
Ejection fraction
If you have increase contractility what happens to the ejection fraction?
Increases
What factors increase Cardiac Output?
1) Increase in EDV
2) Increase in sympathetic activity
3) Increase in epinephrine
4) Decrease in parasympathetic activity
What has more smooth muscle veins or arteries?
Arteries
During systole what happens to the arteries?
Vasodilation
During diastole what happens to the arteries?
Vasoconstriction
If compliance increases what happens to stretch in the arteries?
It increases
What is the maximum pressure reached during the peak of ventricular contraction and ejection?
Systolic pressure (SP)
What is the minimum arterial pressure reached just prior to ventricular ejection?
Diastolic pressure (DP)
what is SP/DP?
Arterial blood pressure
what is SP-DP called?
Pulse pressure
What is the average pressure driving blood to the tissues over cardiac cycle?
Mean arterial pressure
A decrease in arterial compliance occurs in ___________________
arteriosclerosis (stiffening of the arterioles)
In arterials the changes in diameter impacts ________________
blood pressure
If there is vasoconstriction what happens to blood flow?
Less blood flow