airways that supply one lobe of a lung are called respiratory.
airways that supply one lobe of a lung are called?
respiratory
the left main bronchus is smaller in caliber but longer than the right, being 5 cm long. it enters the root of the left lung opposite the sixth thoracic vertebra. it passes beneath the aortic arch, crosses in front of the esophagus, the thoracic duct, and the descending aorta, and has the left pulmonary artery lying at first above, and then in front of it. the left bronchus has no eparterial branch, and therefore it has been supposed by some that there is no upper lobe to the left lung, but that the so-called upper lobe corresponds to the middle lobe of the right lung. the left main bronchus divides into two secondary bronchi or lobar bronchi, to deliver air to the two lobes of the left lung—the superior and the inferior lobe.
bronchus
the earliest vtec-e implementation is a variation of sohc vtec which is used to increase combustion efficiency at low rpm while maintaining the mid range performance of non-vtec engines. vtec-e is the first version of vtec to employ the use of roller rocker arms and because of that, it forgoes the need for having 3 intake lobes for actuating the two valves—two lobes for non-vtec operation (one small and one medium-sized lobe) and one lobe for vtec operation (the biggest lobe). instead, there are two different intake cam profiles per cylinder: a very mild cam lobe with little lift and a normal cam lobe with moderate lift. because of this, at low rpm, when vtec is not engaged, one of the two intake valves is allowed to open only a very small amount due to the mild cam lobe, forcing most of the intake charge through the other open intake valve with the normal cam lobe. this induces swirl of the intake charge which improves air/fuel atomization in the cylinder and allows for a leaner fuel mixture to be used. as the engine's speed and load increase, both valves are needed to supply a sufficient mixture. when engaging vtec mode, a pre-defined threshold for mph (must be moving), rpm and load must be met before the computer actuates a solenoid which directs pressurized oil into a sliding pin, just like with the original vtec. this sliding pin connects the intake rocker arm followers together so that, now, both intake valves are following the "normal" camshaft lobe instead of just one of them. when in vtec, since the "normal" cam lobe has the same timing and lift as the intake cam lobes of the sohc non-vtec engines, both engines have identical performance in the upper powerband assuming everything else is the same.
vtec