Study Guide Unit 3 Flashcards
Function of the valves
Valves prevent back flow of blood. They allow blood to move one way through the heart and body.
Know how systemic circuit differs from pulmonary circuit.
a. Systemic circuit- much longer, higher workload, larger blood volume, higher pressure.
b. Systemic arteries carry oxygenated blood, veins deoxygenated.
c. Pulmonary arteries carry deoxygenated blood and vein carry oxygenated blood.
Coronary circuit
a. Coronary circulation supplies the heart wall.
b. Coronary arteries bring oxygenated blood to myocardium.
c. 2 coronary arteries.
d. Coronary veins collect deoxygenated blood and drain it into the coronary sinus.
Fetal circulation. What is the difference between fetal circulation and circulation after birth?
a. During fetal development the lungs do not function so there is more pressure on the right side of heart. After birth when lung’s function pressure increases on the left side of heart and actually causes more pressure to be on the left side of heart then on the right side of heart.
5 phases of cardiac cycle
atrial systole, early ventricular systole, late ventricular systole, early ventricular diastole, late ventricular diastole
Atrial systole:
atria contracted, and ventricles relaxed, moves remaining blood from atria to ventricles, AV valves open, semilunar valves closed.
Early ventricular systole
beginning of ventricular contraction, ventricular pressure increased more than atrial pressure, AV valves closed-first heart sound is heard, semilunar valves are still closed ventricles should generate more pressure to open them
Late ventricular diastole
atria relaxed, and ventricles contracted, ventricular pressure increases, semilunar valves open, blood ejection termed ventricular ejection
Early ventricular diastole
atria relaxed, and ventricles relaxed, ventricular pressure decreases, blood flowing backward slightly (caught in semilunar valves, which close-second heard sound is heard-S2), prevents backflow into ventricles
Late ventricular diastole
atria relaxed, and ventricles relaxed, ventricular pressure decreased, atrial pressure increased, semilunar valves remain closed, most ventricular filling occurs (70% of EDV)
Cardiac output: definition, CO (CO=SV x HR). factors that affect it (heart rate, SV)
Cardiac output is the amount of blood ejected per set amount of time (usually a minute) This is affected by the stroke volume (average is usually 70 CC) and Heart Rate.
Positive chronotropic agent
(increase cardiac output): sympathetic stimulation-norepinephrine, thyroid hormone, nicotine, and cocaine.
Negative chronotropic agents
(decrease cardiac output): parasympathetic innervation- acetylcholine, beta-blocker.
Know main factors that affect SV
preload, afterload, contractility
Stroke volume
amount of blood ejected in one beat.
Preload
filling time (lower filling time lower EDV, higher filling time higher EDV), venous return (blood volume, H2O, and position).
Contractility
Increased contractility increased stroke volume, decreased contractility decreases stroke volume
Afterload
increases afterload decreases stroke volume, decrease afterload increases stroke volume
Plasma components
92% water. 8% dissolved molecules and ions
Main plasma protein
Albumins
Globulins
Fibrogens
Albumins
Maintain osmotic pressure
Globulins
(alpha and beta transport) (gamma antibodies produced by lymphocytes).
Fibrogen
Blood clot formation or coagulation
RBC recycling
The iron is removed and transported to the liver and red bone marrow by plasma protein transferrin and used to created new RBC.
EPO function
Kidney stimulation increases EPO which increases RBC which increases blood flow which goes to the kidney which stimulates a decrease in EPO which decreases RBC thus decreasing blood flow to the kidney.
Know anatomy of the heart and blood flow
Right atrium – Right atrioventricular valve (tricuspid) – Right ventricle – Pulmonary Semilunar valve – pulmonary trunk – Right/Left pulmonary artery – pulmonary capillaries (O2 enters, CO2 leaves) – pulmonary veins (4) (2 right, 2 left) – Left atrium – Left atrioventricular valve (mitrael, bicuspid) – aortic semilunar valve – aorta – systemic capillaries (O2 leaves, CO2 enters) – veins – superior and inferior vena cava – Right atrium.
Filtration capillary exchange
Occurs on arterial end of capillary
Reabsorption capillary exchange
Movement of fluid back into blood (on the venous end)
Hydrostatic pressure
pushes fluid out of the capillary
blood colloid osmotic pressure
proteins pull water into capillaries
Edema
Is swelling it is an increase in interstitial fluid
Conducting system of the heart: know components, describe electrical events, ECG waves, and cardiac cycle.
P wave
QRS
T wave
PR interval
P wave
Atrial depolarization
QRS
Ventricular depolarization
T wave
Ventricular repolarization
PR interval
Aerial depolarization + delay in AV junction
Arterial BP
pressure exerted on blood vessel walls by blood.
BP
CO x PVR
PVR
is affected by vessel diameter, length, and viscosity
CO
is affected by vessel diameter, length, and viscosity
stroke volume and Heart rate.
These are affected by preload, contractility, and afterload.
Short term control through baroreceptor reflex (explain how)
Long term control through endocrine system (explain how, know in details renin angiotensin aldosterone system)
Three main factors that alter PVR: blood viscosity, total blood vessel length, blood vessel diameter. Which one is the most significant?
Blood vessel diameter is the most significant in the main factors that alter PVR.
Control of arterial blood pressure: short term and long term
Arterial blood pressure is controlled both in the short term (baroreceptor reflex) and in the long term (endocrine system)
Arteries
carry blood away from the heart
Veins
carry blood to the heart
Capillaries
gas exchanges (Pulmonary capillaries- O2 enters CO2 leaves; Systemic capillaries- O2 leaves CO2 enters)
Systolic pressure
the highest pressure experienced by arteries.
Diastolic pressure
baseline pressure in arteries
Pulse pressure
the range of pressure experienced by arteries each heartbeat
Mean arterial pressure
the average pressure in the arteries over time/perfusion pressure N-70-110 mmHg.
Vascular phase
blood vessel constricts, limits blood able to leak from vessel, lasts from few to many minutes.
Platelet plug formation
platelets swell and assume irregular form when in contact with collagen fibers. Become sticky so they can adhere to collagen in tissue. Activated platelets aggregate at the injury site forming the platelet plug.
Coagulation cascade
converts inactive proteins to active form and forms a blood clot. Complex interplay of reactions resulting in the conversion of soluble fibrinogen to insoluble fibrin strands. Clot is composed of meshwork of fibrin fibers entrapping blood cells.
Coagulation requires
calcium, clotting factors, platelets, and vitamin K.
Coagulation; the sympathetic response to blood loss
Homeostasis disturbed falling blood pressure – baroreceptors inhibited – vasomotor centers stimulated, cardioaccelerator centers stimulated, cardioinhibitory centers inhibited – vasoconstriction occurs/increased CO ( increased HR and SV) – Homeostasis restored blood pressure rises – normal range of blood pressure.
