Lab Questions Flashcards
What is the Law of Mass Action?
If the concentration on one side of a reversible rxn increases, the reaction is driven towards the opposite side
What is the principal factor determining the extent of Hb saturation?
PaO2
What does Beer’s Law state?
Concentration of a substance in solution is directly proportional to the amount of light absorbed by the solution
What is the formula for the proportion method which involves absorbance and concentration?
Concentration of known/absorbance of known = concentration of unknown/Absorbance of unknown
What is Drabkin’s reagent?
Drabkin’s reagent is a solution where we dissolve our blood in, and contains potassium cyanide & potassium ferricyanide.
The proportion of Hb that is bound to O2 is referred to as what?
Percent oxyHb saturation (%SO2)
Arterial blood = 97.5%
Venous blood = 75%
What is the formula for total O2 content of blood?
O2 bound to Hb + O2 dissolved in plasma
What are you multiplying to get total amount of O2 dissolved in plasma?
0.003ml O2/100mL blood/mmHg
What do you multiply to get O2 bounded to Hb?
Hb concentration x 1.34 mL O2/g Hb x %SpO2 level
Clinical significance of Hb?
Hb is closely tied to its molecular structure; changes in molecular structure impacts function
What does sickle cell anemia do?
Mutation which then will cause the cells to clump together and obstruct blood flow through capillaries
What is iron-deficiency anemia?
Iron is required for heme-synthesis, & diet deficient in iron impairs Hb production
What is polycythemia?
Abnormal increase in RBC production, Hb concentration increases.
Major functions of Hb?
Transport O2, CO2 and
Buffering H+
Why is the myocardium able to contract?
Electrically conductive which allows them to squeeze
How does the myocardium get stimulated if it is electrically conductive?
Self-stimulation in the absence of neural input
What cells in the right atrium regulate the electrical cycle of the myocardium?
SA node and AV node
What does Isoelectric activity mean?
When the voltage is 0
What is the purpose of ECG signals?
It tells you about the heart rate, rhythm, presence or absence of cardiac hypertrophy, ischemia, infarction
What are the mechanical events of the cardiac cycle?
Cardiac muscle contraction, Opening/Closing of heart valves, blood flow
What is contributing to low and high frequency?
Low: Muscle contraction
High: Valve action + Blood Flow
What is the Lub and Dub associated with on the EKG?
Lub is the closing of the AV valves.
Dub is the closing of aortic and pulmonary semilunar valves at ventricular diastole
What is Phonocardiography?
The technique of recording and displaying heart sounds
What happens to blood flow for someone who is lying in supine position
Venous return ↑ ==> SV ↑
