Main inspiratory muscle is -
Ans. is 'd' i.e., Diaphragm Respiratory musclesInspiratory muscles1. During quiet breathing : Diaphragm (most important), external intercostal and interchondral part of internal intercostal.2. During forced inspiration : Sternocleidomastoid, serratus anterior, serratus posterior superior, pectoral is major and minor, erector spinae, scaleni and levator costarum.Expiratory' muscles1. During quiet breathing : Passive process due to passive recoil of the lungs and thoracic wall.2. During forced expiration : Internal intercostal, innermost intercostal, transversus thoracis, serratus posterior inferior, subcostalis, lattissimus dorsi and abdominal muscles (rectus abdominis, internal and external oblique and transversus abdominis).
Lattissimus dorsi
Transversus thoracis
Serratus anterior
Diaphragm
Thorax