Circulation and Gas Exchange

1) Describe the diversity of basic mechanisms by which animals move molecules (gases, nutrients, waste) throughout their bodies.

2) Compare and contrast an open circulatory and closed circulatory system with respect to anatomy and function.Why do most large and endothermic animals have a closed circulatory system?  Describe the evolutionary trends among animals associated with internal transport systems as they relate to motility, metabolism, and complexity.

3) Compare and contrast the anatomy of the cardiovascular system in each of the following groups of vertebrates: fishes, reptiles and amphibians, birds and mammals.  Explain the physiological significance of each of these circulatory systems to metabolic rate and activity level of the animal.

4) Describe the pathway of blood through the mammalian cardiovascular system, including the heart (chambers and valves), pulmonary and systemic circuits. What is systoleDiastole?  What is the condition (open vs. closed) of the heart valves during each phase of the heart cycle?

5) Describe the electrical excitation of the heart by nodal tissue.  Describe the spread of electrical impulse, during both the systolic and diastolic phases of heart muscle contraction.  What controls the rate of impulse production by nodal tissue?  How does sympathetic and parasympathetic stimulation affect nodal tissue?

6) Describe the basic structure of arteries, veins and capillaries.  How are capillaries different from other blood vessels?  Describe the relationship between blood volume and blood pressure?  Describe the relationship between blood flow velocity and cross-sectional area of blood vessels.

7) What are pre-capillary sphincters and what is their function in the body?

8) Describe the 3 mechanisms of exchange of nutrients, gases, waste, etc... between the blood in capillaries and surrounding interstitial fluid.  If blood pressure is constantly filtering fluid from capillaries, how does blood volume remain constant?  What is the function of the lymphatic system and how does it act to maintain blood volume?  What might cause fluids to accumulate outside the circulatory system?

9) What is blood plasma?  What kinds of molecules do we find dissolved in blood plasma?  Why does blood plasma have a much higher concentration of proteins than interstitial fluid?

10) What are the “cellular elements” of the blood?  Which is most numerous?  What is the BASIC function of each of these elements?  What is a stem cell?  Where might one find them?

11) What is atherosclerosis and arteriosclerosis?  What are the factors that contribute to these diseases?  What role does hypertension play in atherosclerosis and arteriosclerosis?  In heart attacks?

12) Describe the diversity of types of gas exchange organs used by aquatic and terrestrial animals.

13) What are the advantages and disadvantages of using water as the respiratory medium?  How do the gas exchange organs of aquatic animals counteract these disadvantages?  What do we mean by counter-current exchange and how does it increase the efficiency of gills of fishes?  What are the advantages and disadvantages of using air as a respiratory medium? How do the gas exchange organs of terrestrial animals counteract these disadvantages?

14) Describe the pathway of air through the respiratory track of a mammal.  What are alveoli?  Describe the anatomy and function of alveoli and the capillaries that surround alveoli.  How do mammals breathe (i.e. what draws air into and pushes air out of the lungs)?

15) Compare and contrast breathing in birds to that of mammals with respect to how the lungs of birds maximize oxygenation of blood.

16) What is partial pressure and how does it influence the loading and unloading of respiratory gases?

17) Describe the general structure and function of the respiratory pigment - hemoglobin. What is the oxygen dissociation curve and what factors alter hemoglobin’s affinity for oxygen?

18) How is carbon dioxide transported in the blood?

19) What are some adaptations the diving mammals have that allow them to stay under water for long periods of time?