Bones that protrude into the nasal cavity- they increase surface area for filtering dust and dirt particles by the mucous membrane.
Cavities in the skull, ducts connect them to the nasal cavity, lined with mucous membrane to warm and moisten the air. Give resonance to voice.
When food is swallowed, this closes over the opening to the larnyx, preventing food from entering the lungs.
Windpipe. 4.5" long. Walls are alternate bands of membrane and c-shaped rings of hyaline cartilage to keep it open. Lined with ciliated mucous membrane. Coughing and expectoration gets rid of dust-laden mucous.
Similar to trachea with ciliated mucous membrane and hyaline cartilage. Lower end of trachea divides into right and left this.
Thinner walls of smooth muscle, lined with ciliated epithelium. Subdivision of bronci. At the end, alveolar duct and cluster of alveoli.
Composed of single layer of epithelial tissue. Inner surfaces covered with surfactant to keep from collapsing. Each surrounded by capillaries. Oxygen and carbon dioxide exchange takes place between these and capillaries.
Thin, moist, slippery membrane that covers lungs. Double-walled sac. Space is pleural cavity- filled with pleural fluid to prevent friciton.
functions of the respiratory system
Respiration (external, internal, and cellular). Production of sound (vocal cords). Pulmonary venilation. Inspiration (intercostal muscles lift ribs outward, sternum rises and the diaphragm contracts and moves downward- this increases the volume of the lungs and the air rushes in).
1 inspiration and 1 expiration= 1 respiration. Normal adult= 14-20 respirations per minute. Increases with exercise, body temperature, and certain diseases. Age (newborn= 40-60 per minute). Sleep= respirations go down. Emotion can bring respirations up or down.
Spasm of diaphragm and spasmotic closure of the glottis- irritation to diaphragm or phrenic nerve.
neural factors of breathing control
Respiratory center located in medulla oblongata (in the brain). Increase in CO2 and decrease in O2 in the blood will trigger respiratory center.