Blood
What are the formed elements of blood after being centrifuged?
RBCs, WBCs, platelets
Is it normal for a patient to have a WBC count of 50,000/mm3? What does this usually suggest?
No, it is way above normal and it could suggest leukemia
What mechanical event causes the first heart sound (lub)?
The closure of the AV valves
Which vessel layer is the only layer present in capillaries
Tunica interna because it allows efficient exchange
A typical blood pressure reading reflects pressure in which vessels and during which phases?
Arteries during ventricular systole and diastole
Why don't the red blood cells survive for more than 120 days
They have no nucleus, so no synthesizing new proteins to repair damage
A patient has a parasitic worm infection, which leukocyte increases?
Eosinophils will increase
On the ECG, what electrical do the P, QRS, and T wave represent, and what mechanical event follows them?
P: Atrial depolarization and atrial contraction
QRS: Ventricular depolarization and ventricular contraction
T: Ventricular repolarization and ventricular relaxation
Which layer of arteries is much thicker than the veins? How does that relate to its function?
The tunica media; it has thicker smooth muscles which allow the arteries to withstand higher pressure
Why is MAP considered a better indicator of tissue perfusion than systolic pressure alone?
It reflects the average pressure pushing blood though tissues over the entire cardiac cycle
A person has type B+ blood, what are the antigens and antibodies?
Antigens: B and Rh
Antibodies: anti A
Why is vasospasm considered the first and beneficial response to vessel damage?
It immediately reduces the blood flow and it limits blood loss by constricting the damaged vessel
Why is there a delay of the electrical impulse at the AV node, and why is this delay important for proper cardiac function?
It allows time for the atria to fully contract and empty blood into the ventricles before ventricular contraction. It ensures efficient ventricular filling and coordinated pumping
A patient experiences vasoconstriction of peripheral arterioles. What happens to peripheral resistance and to blood pressure?
They both increase because narrowing arterioles decreases the vessel radius which increases resistance
What structural feature if arterioles allow them to control peripheral resistance? During vasoconstriction, what happens to Bp?
Thick tunica media w/ smooth muscle cells allowing them to change diameter
Vasoconstriction increases peripheral resistance and raises blood pressure
As the number of erythrocytes in circulation increases, what happens to the oxygen carrying capacity and why?
It will increase because there will be more hemoglobin available to bind and transport O2
Explain the blood clotting in order
1. Vasospasm
2. Platelet plug formation
3. Prothrombin into Thrombin
4. Fibrinogen into Fibrin
5. Stable clot formation
Explain the cardiac conduction system in order
SA node -> internodal fibers -> AV node -> AV bundle -> bundle branches -> Purkinje fibers
At the arterial end of a capillary, fluid moves out of the capillary. What is this pressure called and why does the fluid move in that direction at the arterial end?
Hydrostatic pressure, it is greater than the osmotic pressure, so the net movement is out of the capillary into the tissues
Arterial end, fluid is pushed out into the interstitial space. Which pressure is greater at the arterial end? The venular end? Why is the lymphatic system necessary?
Hydrostatic
Osmotic
Not all filtered fluid returns to the capillary, so it will be collected and returned
Explain erythropoiesis in order
1. Low O2 is detected by kidneys
2. Kidneys release erythropoietin
3. Erythropoietin stimulates in red bone marrow
4. Increased RBC production
5. O2 carrying capacity rises
Explain the hemoglobin recycling in order
1. Hemoglobin splits into heme & globin
2. Globin is recycled into amino acids
3. Heme is broken down into iron & biliverdin
4. Iron is recycled
5. Biliverdin is converted into bilirubin then excreted into bile
Explain the cardiac cycle in order
1. Late diastole
2. Atrial systole
3. Isovolumic ventricular contraction (lub)
4. Ventricular ejection
5. Isovolumic ventricular relaxation (dub)
6. Cycle repeats
Where are continuous capillaries most likely found?
The brain because tight control is need for the blood brain barrier
Explain the blood flow pathway in order
Vena cava (I/S), RA, tricuspid valve, RV, Pulmonary semilunar valve, Pulmonary trunk/arteries, lungs, Pulmonary veins, LA, Mitral valve, Left ventricle, Aortic semilunar valve, Aorta, Body