Respiratory Respiratory SystemSystem

Anatomy and PhysiologyAnatomy and Physiology

Chapter 13Chapter 13

Upper Respiratory TractUpper 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.

PharynxPharynx• 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

LarynxLarynx• 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 - Lower Respiratory Tract - TracheaTrachea

• 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 - lungsExternal 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

BronchiBronchi• 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 - lungsInternal 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

CO2 is dropped off

O2 picked up

Here is a close

up picture of

your Alveoli

and a Capillary

surrounding it.

Lung VolumesLung 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