Intro To Respiration

Question 1

Respiration at external and internal level

Answer 1

. External respiration: Exchange of gases btw atmosphere and body tissues
. Internal: cellular oxidative metabolism at tissue level

Question 2

Ventilation

Answer 2

Movement of gas into and out of lungs

Question 3

Primary functions of respiratory system

Answer 3

. Obtaining oxygen from the environment, removing CO2 rom body
. Help regulate body’s acid/base balance

Question 4

Respiratory system secondary functions

Answer 4

. Produce sounds for communication
. Defend against microbes that try to enter body
. Lungs act as blood reservoir, esp. in supine position
. AI converted to AII via ACE in lungs
. Bradykinin and serotonin removed or inactivated in pulmonary circulation via pulmonary endothelial cells that line capillaries
. Trap and dissolve blood clots

Question 5

What traps particles larger then 10 um in respiratory system?

Answer 5

. Hairs and mucopolysaccharides within nasal passage

Question 6

What traps particles under 10 um in respiratory system

Answer 6

. Tapped and eliminated from pharynx and larynx through mucociliary elevator
. Lymphoid tissue in tonsils and adenoids also provide immunological defense

Question 7

Components of conducting division of respiratory system

Answer 7

. Nose 
. Paranasal sinuses 
. Pharynx
. Larynx
. Trachea
. Bronchial tree through terminal bronchioles

Question 8

Nose function w/ respiratory system

Answer 8

. Warm, moisten, and filter inspired air
. Dehumidify and cool expired air
. Essential to gas exchange bc O2 and CO2 can’t diffuse through dry membranes
. Vibrissae nose hair) filer particles and then rest are trapped via mucous membranes on nasal conchae

Question 9

Paranasal sinuses role in respiratory system

Answer 9

. Frontal, sphenoidal, ethmoidal, maxillary
. Warm and moisten inspired air
. Dec. weight of skull

Question 10

Pharynx role in respiratory system

Answer 10

. Works in respiratory and digestive systems
. Nasopharynx is respiration only and provides connection w, middle ear via Eustachian tube
. Oropharynx is both food and inhaled air

Question 11

Larynx role in respiratory system

Answer 11

. Epiglottis prevents swallowed things from reaching lungs
. Involved in sound production
. Mucosal surface as pseudostratified ciliated columnar epithelium for protection

Question 12

Trachea role in respiratory system

Answer 12

. Connects larynx to lungs
. 16-20 hyaline rings
. Mucosal lining is pseudostratified ciliated columnar epithelium

Question 13

Bronchial tree up to terminal bronchioles

Answer 13

. 23 levels of branching
. No gas exchange in 1st 16 branches (conducting division)
. Primary bronchi: divide to make eco dairy bronchi then divide again for tertiary/segmental bronchi
. Walls have smooth mm. And irregular cartilage plates
. Walls can constrict or relax changing diameter of bronchi
. Branching continues until terminal bronchioles that contain no cartilage and mark end of conducting division

Question 14

Respiratory division of respiratory system

Answer 14

. Has 7 levels of branching
. Respiratory bronchioles -> alveolar ducts -> alveolar sacs
. Gas exchange only occurs here
. Alveoli is supported by parenchyma (mesh CT w/ elastin and collagen)
. Total SA for gas exchange 60-80 m2
. Has dense vascular beds (100 capillaries per alveolus)

Question 15

Acinus

Answer 15

. Portion of lung supplied by primary respiratory bronchiole
. Branches into 100 alveolar ducts that terminate in 20 alveoli each

Question 16

Types of alveolar cells

Answer 16

. 1 cell layer thick
. Type 1 alveolar cells: form major part of alveolar wallas and permits diffusion
. Type 2 cells: secrete surfactant (lipoprotein)

Question 17

Surfactant function

Answer 17

. Helps prevent alveolar collapse by dec. surface tension of alveoli

Question 18

Where are alveolar macrophages found?

Answer 18

. W/in the alveolar lumen

Question 19

Airway epithelium

Answer 19

. Mostly pseudostratified ciliated columnar epithelium w/ goblet cells, form mucociliary escalator
. Inside lung the epithelium thins to simple cuboidal them simple squamous for gas exchange

Question 20

Pleurae

Answer 20

. Serous membranes that surround lung and line thoracic cavity
. Visceral pleura adheres to outer lung surface
. Parietal pleura lines thoracic walls and thoracic surface of diaphragm
. Continuation of parietal pleura around heart and btw lungs found mediastinum boundary
. Pleural cavity btw visceral and parietal pleurae and has fluid that allowed lungs movement (considered potential space)