Science Homework Help

help answer a few questions must be detailed answer should be 1-2 paragraphs.1. Hearts are vascular pumps, but the myocardium also needs an oxygen supply. Use a comparative approach to discuss different solutions to this problem in mammals and birds; in teleost fish; and in tunas, salmonid fish and sharks. Feel free to use your artistic skills to draw the structure of spongy and compact myocardia in relation to their vascular supply. (10 points)

2. Discuss the differences between myogenic and neurogenic hearts, and explain what is the role of regulatory neurons to control cardiac output. If possible, include in your answer examples from different organisms for each type of heart. (10 points)

3. Explain how the cross sectional area of vessels (in cm2, range from 0 to 5000) affects the mean linear velocity of blood (in cm/s, range from 0 to 50) and blood pressure (in mm Hg, range from 0 to 100). Hint, draw a general model of vascular structure from the aorta to the vena cava, and plot how the variables mentioned above change as blood moves along the vessel system. (10 points)

4. Why is the pulmonary circulation considered to be a circuit that keeps the lungs dry? (10 points)

5. Discuss the physiological role of countercurrent mechanisms and blood pressure in water regulation. (10 points)

6. List the major types of blood vessels in the systemic circuit of a mammal, and outline the functions of each type of vessel. (10 points)

7. Explain what is the relationship between flow rate, the difference in blood pressure between the two ends of a horizontal vessel system and the resistance of blood to flow in the horizontal vessel system. Think of the analogy between blood flow and Ohm’s law. Include in your answer what is the role of vasomotion in flow rate. (1