All of the following statements about bronchial circulation are true, Except:

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 1/3 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 2/3rd 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.