The respiratory tracts- Structure and function, pulmonary gas exchange mechanics of respiratory, compliance surfactant, lung volumes and capacities uptake and delivery of respiratory gasses with reference to oxygen and carbon dioxide transport. Pulmonary function test, response to hypoxia higher altitude, exercises etc.  Artificial respiratory, chemical and neural control of respiration.  Organization and structure of aorta and large arteries and arterioles- as resistance vessels, capillaries as sites of tissues fluid exchange. The heart - Properties and functions of cardiac muscles.  Regulation of heart’s rate and cardiac output.  Bar receptors and control of arterial blood pressure. Regional circulation, heart, hemorrhage, exercises, posture and altitude.