Docstoc

Respiratory System Notes Anatomy

Document Sample
Respiratory System Notes Anatomy Powered By Docstoc
					                                       Respiratory System
       Main purpose: supply body with oxygen and get rid of carbon dioxide.
Respiration:
     1. pulmonary ventilation- breathing
     2. external respiration- gas exchange between blood and lungs
     3. transport of gases- cardiovascular system moves gases
     4. internal respiration- happens at capillaries
Functional Anatomy-
      Respiration zone= bronchioles, alveoli (microscopic)
      Conducting zone= all other respiratory passages
      Cleanse, humidify, warm air
*Nose- external part- 1) Provides airway; 2) Moistens and warms air; 3) Filters; 4) Speech-
resonating chamber; 5) Smell receptors
External nose-
      root, bridge, apes
      shallow vertical groove beneath nose= philtrum
      external nares= nostrils
Internal nasal cavity;
      divided by nasal septum (vomer, ethmoid bones and cartilage), internal nares
Hard and soft palate- maxilla and palatine bones; support nasal cavity
1. Olfactory mucosa (smell)
2. Respiratory mucosa (goblet cells, mucus, and lysozyme) has cilia to move contaminated mucus
to be swallowed
       (Cilia become sluggish on cold days= runny nose), lots of veins warm incoming air; when
           dust, pollen, etc. trigger nerve endings, we sneeze
* Paranasal Sinuses- lighten skull, warm and moisten air, produce mucus
- Rhinitis- cold viruses, allergens- inflammation of nasal sinuses- congestion, postnasal drip
- Sinusitis- inflamed sinuses; sinus headaches, changes in voice
* Pharynx- common pathway for food and air (throat); 3 regions:
          1. nasopharynx- air passageway (close it off); soft palate and uvula
          2. oropharynx- food and air passageway
          3. oarnogopharynx- food and air
- 3 types of tonsils- 1) adenoids; 2) palantine; 3) lingual
* Larynx- voice box; 3 functions:
          1) Open airway; 2) routes food and air into correct passages; 3) voice production
- 9 cartilages- all but epiglottis are hyaline; one of these is the Adam’s apple (usually bigger in
males)
Epiglottis- spoon- shaped, flexible, elastic cartilage, covered with taste buds, covers the respiratory
passages when swallowing
Vocal ligaments- elastic fibers
      along with mucosal folds make up the true vocal cords
      vibrate and make sound as air goes by glottis- opening through which air passes
      tenser vocal cords= faster vibrations= higher pitch
     - larynx enlarges and vocal folds elongate and thicken during puberty in males
     - greater force= louder
     - cavities in nose, sinuses add resonance
Laryngitis- inflammation of vocal cords; hoarseness
*Trachea- windpipe; very flexible has cilia
               Smoking destroys these cilia; can only cough to remove mucus from lungs
               Has 16-20 rings of hyaline cartilage to keep airway open
               Heimlich maneuver removes food caught in trachea (abdominal thrust)
*Bronchi-
     right and left primary bronchi branch off trachea
     then divide into secondary (lobar) bronchi- 3 on right, 2 on left (on per lobe)
     then tertiary (segmental)
     about 23 different levels of bronchi
*Bronchioles- under 1mm in diameter
Then terminal (end) bronchioles
As tubes become smaller:
     cartilage rings become irregular plates & disappear by bronchioles (do have elastic fibers
         though)
     pseudostrat. columnar epithelium switches to columnar, then cuboidal in terminal
         bronchioles
     cilia are sparse; mucus –producing cells disappear
     smooth muscle increases
*Alveoli- sites of gas exchange
Alveolar sacs- terminal clusters of alveoli
     Approx. 300 million alveoli in lungs
     Smaller thickness than a sheet of tissue paper
     Lots of capillaries- gas exchange occurs by diffusion across fused alveolar/capill.
         membranes
     Dust cells- macrophages that remove microorganisms
* Lungs- left lung is smaller- 2 lobes (upper & lower)
     Right lung- 3 lobes (upper, middle, & lower)
     Bronchopulmonary segments- pyramid-shaped, separated by septa- each has its own
         artery, vein, and segmental bronchus
     Smallest subdivision seen with naked eye- lobule
     Stroma- elastic conn. Tissue in lungs
     Soft, spongy, approx. 2.5 lbs together

				
DOCUMENT INFO