CH 11-13 cardio system Flashcards
Primary functions of blood
Transportation- nutrients, waste, products, gases, hormones
Regulation- fluid-electrolyte balance, acid-base balance, body temperature
Protection- against pathogens by wbc and the blood clotting mechanism
stabilization of body temperature
Restriction of fluid losses at injury sites
Composition of blood
Blood is a complex connective tissue in which living blood cells, the formed elements are suspended in a nonliving fluid matrix called plasma.
Formed elements (rbc, wbc, and platelets) (45%of volume) suspended in a nonliving fluid plasma (55%) of volume
What is plasma?
55% of whole blood. Plasma is the liquid part of blood and is appox. 92% water
Transports: Proteins (albumin) Nutrients Waste products Hormones Antibodies
Hormones produced by endocrine glands are carried in the plasma to their target organs.
Plasma proteins
The other 9% (by volume) of the plasma is made up of circulating plasma proteins
Clotting factors- circulate until activated to form a clot in a ruptured or damaged blood vessel.
Formed elements
1 molecule of hemoglobin= 4 molecules of O2
RBC, WBC, and platelets (cell fragments that clot)
Accounts for 45% of whole blood
What does aspirin do to platelets?
Makes them not stick. So they won’t continue to clot.
RBC transport what?
Also known as erythrocytes, transport o2 and CO2
WBC function?
Also called leukocytes
Part of the body’s defense mechanism
Ph of blood
Co2 normal levels of blood
7.35 to 7.45
35-45
Albumins
Constitue 60% of all plasma proteins
Major contributor to osmotic pressure
Globulins
Constitue 35% of plasma proteins Includes antibodies and transport proteins Antibodies, also called immunoglobulins Attack foreign proteins and pathogens Transport proteins
Fibrinogen
Functions in blood clotting
Form large insoluble strands of fibrin.
Which part of blood doesn’t clot?
Serum-Fluid that remains after clotting proteins removed
What does the liver do for blood?
Synthesizes more than 90% of plasma proteins (al albumins and fibrinogen)
Most globulins
Liver disorder=clotting problems
What do antibodies take out?
Antigens. They also neutralize them.
3 formed elements
RBC=erythrocytes
WBC= leukocytes
Platelets= Cell fragments for clotting
Purpose of hemoglobin
A protein Binds and transports oxygen and carbon dioxide
Misfolded hemoglobin= sickle cell anemia
Anemia
Blood has a low hematocrit (low oxygen carrying capacity)
RBC’s have reduced hemoglobin content which results in reduced oxygen carrying capacity
Jaundice
Caused when bile ducts are blocked
Hep A
Bilirubin defuses into peripheral tissues
Causes a yellowing of the skin and sclera
Erythropoieses
Red blood cell formation
Occurs in red bone marrow or myeloid tissue
Antigen
Substances that can trigger an immune response
Surface antigens
Present on all cells
Recognized as normal by immune defenses
RBC and 3 antigens of blood type
Presence or absence of 3 antigens determines blood type.
A, B, Rh
Type A has antigen A only
Type B has antigen B only
Type AB has both antigen A and B
Type O has neither antigen A nor B
antigen vs antibody
Antigen is attached to the cell
Antibody is attached to the plasma.
Antigen type A on cell, looing for type B in plasma
Agglutinaion
RBC’s clumping together when foreign blood cells enter the blood stream. B antigen and B on plasma bind together
WBC’s differences from RBC’s
Larger size
Nucleus and other organelles present
Lack hemoglobin
Defend the body against pathogen invasion
Remove toxins, wastes, and abnormal damaged cells
heparin and histamine
heparin- prevents blood clotting
Histamine- enhances local inflammation initiated by mast cells in damaged tissues
Leukopenia vs leukocytosis
Leukopenia- indicates a reduced quantity of WBC’s
Leukocytosis- refers to an excessive of WBC’s (leukemia)
Cancer of blood-forming tissue
normal WBc count is 5000-10000
Low platelet count
Referred to as thrombocytopenia
Less than 80,000 per microliter
thrombocytosis
Platelet count exceeds 1,000,000
Results from accelerated platelet formation
Response to infection, inflammation, or cancer
3 overlapping phases of homeostasis
Phase 1: vascular phase: vascular spasm, local contraction triggered by cutting the wall of a blood vessel, vasoconstrict, lasts about 30 minutes
Phase 2: platelet phase: Platelets attach to sticky endothelial surfaces and exposed collagen fibers, begins within 15 seconds of the injury
more platelets arrive and attach to each other, mass of platelets that may close the break in the vessel wall
Phase 3: coagulation phase: Does not start for more than 30 seconds after vessel is damages. Coagulation; blood clotting
Fibrinogen*
Becomes fibrin threads
3 pathways for blood clot formation
Extrinsic pathway: begins outside the bloodstream, in the vessel wall. Factor 7 and factor 10. Another clotting protein, forms an enzyme capable of activating factor 10
Intrinsic pathway: begins inside the bloodstream
Common pathway is the joining of the 2 other pathways
Common pathway*
Begins with the activation of factor 10
factor 10 forms the enzyme prothrombinase
converts the clotting protein prothrombin into the enzyme thrombin
Thrombin converts fibrinogen to fibrin.
3 major types of blood vessels
Arteriers: Carry blood away from the heart
Capillaries: which enable the actual exchange of water and chemicals between the blood and the tissues
Veins: carry blood from the capillaries back toward the heart
3 layers of arteries and veins*
Tunica interna (thinnest layer)
Tunica Media (thickest layer in arteries) Rich in vascular smooth muscle in a framework of connective tissue composed of mostly elastin with some collagen fibers
Tunica externa (tunica adventitia) (thickest layer in veins)
Artery vs vein
Artery is high pressure
Arteries don’t have valves
Arteries have a thick tunica media
Vein is low
Vein has a valve
Veins have a thick tunica externa
Blood flow through heart and lungs
Right A to right V to pulmonary artery, (only artery that carries deoxygenated blood). Goes to capillary network around alveoli. Pulmonary artery to pulmonary vein (only vein to carry oxygenated blood) which goes to left A to left V pumps blood to rest of body.
Sytolic vs diastolic
Systolic pressure is the pressure of your heart at contraction
Diastolic is the pressure of your heart at rest
Pulse pressure
Difference between the systolic and diastolic pressures. Want it to be around around 40
How to find mean arterial pressure
Take diastolic pressure, multiply it by 2, add it to systolic, divide it by 3.
Want it over 60.
What is cardiac output*
Cardiac output=Heart rate x stroke volume
How much blood is coming out with each contraction
Hepatic portal system
Drain in the organs of digestion to the liver
The hepatic portal system does just that by absorbing the nutrients, wastes and toxins from the digestive system and transporting them to the liver for processing before they make their way into the system.
Pulmonary circuit vs systemic circuit
Pulmonary circuit: carries blood to and from exchange surfaces of the lungs
Systemic: transports blood to and from the rest of the body
Arteries
Efferent vessels
Carry blood away from the heart
Heart Right side
Right atrium: receives blood from systemic circuit
Right ventricle: Discharges blood into pulmonary circuit
Heart left side
Left atrium: receives blood from pulmonary circuit
left ventricle: discharges blood into the systemic circuit
Top two beat at the same time, bottom two beat at the same time.
visceral pericardium
Also referred to as the epicardium, covers the outer surface of the heart
Parietal paricardium
Lines the inner surface of the pericardial sac
3 distance layers of the heart
Epicardium or visceral pericardium: covers the outer surface of the heart
Myocardium: muscular wall of the heart
Endocardium: covers the hearts inner surfaces and valves
Atrioventricular valve
Opens between the atria and ventricle on the same side
Ensures a one way flow of blood
Valves TPMA
Tricuspid Valve: right atrium to right ventricle
Pulmonary valve: right ventricle to pulmonary vein
Mitral or bicuspid valve: left atrium to left ventricle
Aortic valve: left ventricle to ascending aorta
Blood supply to the heart
Right coronary artery: supplies to the right atrium, supplies blood to portions of both ventricles
Left coronary artery: supplies blood to left atrium, supplies blood to the left ventricle
2 branches of the left coronary artery
Circumflex branch
Anterior inter ventricular (descending) branch
Infarction
Area of dead tissue
Caused by interruption in blood flow
Myocardial infarction
Coronary circulation becomes blocked
Cardiac muscle cells die from a lack of oxygen
Most often occurs as a result of coronary artery disease (build up of fatty deposits in the walls of the coronary arteries)
Contractile cells
99% of all cardiac muscle cells
Action potential in ventricular muscle cells proceeds in 3 steps
Step 1 Rapid depolarization: sodium channels open, influx of sodium depolarizes the sarcolemma, sodium channels close when transmembrane potential reaches +30 mV
Step 2: plateau: cell begins to actively pump sodium out, calcium channels open, calcium gain roughly balances sodium loss
Step 3: repolarization: Calcium channels begin to close, potassium channels open and rushes out of the cell, and restores the resting potential
The normal rate of contraction is established by
Pacemaker cells.
Location of pacemaker cells
SA node (sinoatrial) AV node (atrioventricular) Purkinje fibers
Bradycardia vs tachycardia
brady: HR below 60
Tachy: HR above 100
P wave
atrial depolarization
QRS complex
ventricles depolarization
T wave
Ventricular repolarization
Stroke volume is..
Amount ejected by 1 ventricle
Cardiac output is..
CO= SV x HR
Amount pumped by each ventricle in 1 minute
Frank-starling principle
More in=more out
More cardiac muscle is stretched the stronger contraction and better cardiac output you get
