Biology Questions

Biology Questions


Directions: Answer each question below in an essay format.You are required to use at least 3 references (published research studies; no: magazine articles, websites, or textbooks) in each response.  I do not care what format you use to make your bibliography (APA, Chicago), just be consistent throughout.  Each answer should be typed with proper grammar and punctuation.  You will be graded on the content along with your writing.  The length of each response is up to you, be concise, but be complete. Please take pride in your responses, and demonstrate your advanced understanding of these topics.


NOTE: this is an individual assignment, and I want you to think on your own.  I ask that you not work in groups and refrain from consultation with colleagues.



1.     Please discuss the mechanisms of how cardiac output increases during exercise (provide mechanisms for each component).  Please discuss why cardiac output might decrease at high heart rates and during advanced arrhythmias such as ventricular tachycardia.



2.     Please describe how the heart increases oxygen consumption during exercise.  In your response, discuss the following: 1. The myocardial supply and demand components; and 2. The components of Fick equation as it relates to myocardial oxygen consumption (MVO2 = Q x a-V O2diff).  If you recall, one component is at or near capacity, please explain.



3.     Discuss how blood pressure is maintained during exercise, and the major components that influence blood pressure during exercise.  What does a drop in SBP during exercise represent in terms of hemodynamics and why?



4.     Describe the mechanisms (3 discussed) that prepare and influence (i.e., the pre-emptive response) the cardiovascular response to acute exercise.



5.     As discussed, the heart is under intrinsic (pacemaker) and extrinsic control (autonomic).  What are the mechanisms of how the pacemaker alters heart rate (i.e., pacemaker action potential), and how does the autonomic nervous system influence each of these mechanisms?