It all starts with the nose. OK, in humans maybe not the nose pictured above, but one similar to the nose below. Though the passage of air is probably similar in cows and humans. Air comes in and then where does it go?
The organs of the respiratory system that bring air into the body are divided among the upper respiratory tract and lower respiratory tract. These organs are shown in Figure below. In addition to the lungs, these organs include the pharynx, larynx, trachea and bronchi. The nasal cavity is also part of the respiratory system. The nose and nasal cavity filter, warm, and moisten the air we inhale. Hairs and mucus produced in the nose trap particles in the air and prevent them from reaching the lungs.
The organs of the respiratory system move air into and out of the body.