Week 1 Scholarly Questions and Analytical Thinking

Review and know the main structures of the heart.
What are the wall thicknesses (mm) of the different chambers of the heart? CHECK your answer below.
What is a pressure gradient and how does it relate to blood flow through the heart.
Know the blood flow through the pulmonary and systemic circuit TEST yourself at this LINK
How much blood passes from the atrial to the ventricles (in %) before the atria contract. What is another name for the atrial contraction? (answer: atrial 'kick' from our text)
Explain and describe the cardiac cycle. There are THREE specific phases. CHECK YOUR WORK AT THIS LINK
Who is William Harvey? Who is Augustus Waller? Who is Willem Einthoven?
What does autoconduction mean? What is another name for autoconduction? (If you answered pacemaker or autorhythmic you are correct)
Explain in detail the cardiac electrical conduction system. Starting from the SA node, make sure you can draw and explain the electrical conduction pathway to the purkinje fibers. CHECK YOUR WORK HERE. What is Bachmann's bundle (name after Jean George Bachman)? What does the word sinus mean (from Latin roots)? (Yes, sinus is Latin for 'pocket' or 'curve,' The SA node is actually shaped like an almond nut.

Cardiovascular physiology review
Explain depolarization and repolarization.
What is the difference in efflux and influx?
Note (just for observation, NOT for exam) the difference and similarities in skeletal muscle motor unit (nerve, neuromuscular junction, muscle cell) activation and cardiac muscle (autorhythmic cell, gap junction, cardiac contractile cell) activation.
Name and Explain in DETAIL all Phases of Depolarization and Repolarization of a cardiac contractile cell. Make sure you state the ions associated with each Phase (differentiate the slow and fast sodium channels) CHECK YOUR WORK HERE.
What are the two main types of heart cells we are discussing in class? (i.e., pacemaker and contractile)
A vector has direction and amplitude. An EKG tracing is a vector?
As the cell depolarizes, is the inside of the cell becoming more positive or negative?
As depolarization advances TOWARDS a positive electrode, which way is the deflection on the tracing?
As depolarization advances TOWARDS a negative electrode, which way is the deflection on the tracing?
As depolarization advances PERPENDICULAR TO A lead, which way is the deflection on the tracing?
What does biphasic mean with an EKG deflection?
CHECK YOUR WORK ABOVE AT THIS LINK
Describe an EKG tracing and explain what is happening electrically and mechanically (i.e, P wave is atrial depolarization, QRS is....etc).

ANSWER TO WALL THICKNESS QUESTION ABOVE:
Right atrial wall=2mm
Left atrial wall=3mm
Right ventricle wall=3-5mm
Left ventricle wall=13-15mm

EKG Page