<prompt> All of the following statements about bronchial circulation are true, Except:Contribute 2 of systemic circulationContribute to gaseous exchangeCause venous admixing of bloodProvide nutritive function to lung  <response>: B i.e. Contribute to gaseous exchangeBronchial circulation does not take pa in gaseous exhangeQ. Gaseous exchange takes place in pulmonary circulation.Bronchial Circulation- Bronchial aeries arise directly from aoa and provide nourishment oxygenated blood to lung parenchymaQ. Bronchial aeries are usually 3 in number, accompany the bronchial tree and divide with it.- The main function of bronchial aery is to provide oxygenated systemic blood nutrition to lungs i.e. walls of conducting airways bronchi, bronchioles down to and including respiratory bronchioles, blood vessels eg pulmonary aeries, nerves, lymph nodes and most of the visceral pleura.- Bronchial circulation receives 1-2 of total cardiac output, which increases as much as 10 to 20 of CO in cystic fibrosis. Approximately 13 of blood returns to right atrium bronchial veins; whereas the remainder drains into the left atrium pulmonary veins. The erosion of inflamed tissue into these vessels secondary to bacterial infection is responsible for hemoptysis.- Bronchial circulation causes venous admixingQ i.e. mixing of un-oxygenated bronchial venous blood directly into oxygenated pulmonary venous blood as its 23rd blood returns through pulmonary veins.- Gaseous exchange i.e. removal of CO2 from deoxygenated blood and mixing of 02 oxygenation takes place in pulmonary circulation of lung. 