Respiratory System Anatomy and Physiology Chapter 13

Upper Respiratory Tract Air enters nose then nasal cavities Nasal cavity has ridges – conchae Ridges have mucous - cleanse dust particles and cause turbulence in air flow Hairs prevent large particles from entering nose Air in lungs saturated with water vapor and warmed to body temp.

Pharynx Pharynx air passes into pharynx from nasal cavity passageway for both food and air Tonsils located here Lower portion called glottis – opening to larynx Epiglottis – flap of tissue that covers glottis during swallowing

Larynx voice box or Adam’s apple Vocal cords are attached (2) – elastic ligaments Greater air pressure = louder sound Glottis changes shape – different qualities of voice

Lower Respiratory Tract - Trachea Slightly flat tube Heimlich maneuver – forcibly raises diaphragm to dislodge food Esophagus – lies just behind trachea Esophagus will enlarge against trachea – discomfort swallowing large food Your trachea is held open by “incomplete rings of cartilage.”

External structure - lungs Cone shape Pleural portion of thoracic cavity Apex – upper border – above clavicle Enclosed by thoracic cavity External area indented to allow space for heart

Bronchi Trachea divides into 2 tubes - primary bronchi, mucous lined Bronchi divide into secondary bronchi These divide into bronchioles then alveoli Estimated ~ 300 million in both lungs

Internal Structure - lungs Bronchioles and alveoli - structures within lungs Divided into superior and inferior lobe Pleural cavity – space with fluid prevents friction Right (3 lobes)slightly larger than left(2 lobes)

RBC Capillary CO 2 is dropped off O 2 picked up Here is a close up picture of your Alveoli and a Capillary surrounding it.

Lung Volumes Lungs can hold up to 5.7 liters – males 4.2 liters – females Vital capacity – air volume that moves out of lungs in one breath after maximum inhalation Tidal volume – volume of air flowing into or out of lungs in respiratory cycle. -.5 liters

* At rest, the body takes in and breathes out about 10 liters of air each minute. * The right lung is slightly larger than the left. * The highest recorded "sneeze speed" is 165 km per hour. * The surface area of the lungs is roughly the same size as a tennis court. * The capillaries in the lungs would extend 1,600 kilometers if placed end to end. * We lose half a liter of water a day through breathing. This is the water vapor we see when we breathe onto glass. * A person at rest usually breathes between 12 and 15 times a minute. * The breathing rate is faster in children and women than in men. Fun Facts