Chapter 9 Flashcards
Where do single-cell eukaryotes that require oxygen to perform oxidative phosphorylation acquire it
Simple diffusion of oxygen from the surrounding medium
Ventilation
Simple movement of air in and out of the lung properly
Respiration
exchange of gases (between lungs and blood or other tissues of the body)
Conduction Zone
Parts of the respiratory system involved only in ventilation
Respiratory Zone
parts of the respiratory system involved in actual gas exchange
The respiratory system other tasks
pH regulation, thermoregulation, protection from diseases and particulate matter (mucociliary escalator, alveolar macrophages)
Pathway followed by inhaled air
nose -> nasal cavity -> pharynx -> larynx -> trachea -> primary bronchi -> bronchioles -> terminal bronchioles -> respiratory bronchioles -> alveolar duct -> alveoli
Nose
warming, humidifying and filtering inhaled air. Nasal hairs and sticky mucus act as filters
Nasal cavity
open space within the nose
Pharynx
throat (common pathway for air and food)
Larynx
made entirely out of cartilage to keep airway open, contains epiglottis which seals the trachea during swallowing, contains vocal chords
Trachea
passageway which remains open to permit airflow. Rings of cartilage prevent its collapse
Primary bronchi
Two; each one supplies one lung, collapse is prevented by small plates of cartilage
Bronchioles
1mm wide, contain no cartilage, made out of smooth muscle which allows their diameters to be regulated to adjust airflow
Terminal Bronchioles
final and smallest branches of the conduction system. Smooth muscle walls are too thick to allow for gas exchange
Alveoli
Structures across which gas diffuses. Very thin, one cell thick
What type of cell lines the entire respiratory tract
Epithelial columnar cells; too thick to assist in gas exchange and serve as a conduit for air, but some are specialized to secret mucus (goblet cells)
Mucociliary Escalator
columnar epithelial cells of the upper respiratory tract have cilia which constantly sweep mucus towards the pharynx where they can be swallowed or coughed out
What structures are involved in gas exchange
Alveoli, alveolar ducts and the smallest bonchioles
What type of cells line gas exchange surfaces
single layer of thin delicate squamous epithelial cells
What method of protection do thin squamous epithelial cells use
Alveolar macrophages patrol the alveoli, engulfing foreign particles
Surfactant
Coats the alveoli, reduces surface tension to prevent collapse of the alveolar wall (fat cubodial epithelial cells secret surfactant)
Pulmonary Ventilation
Circulation of air into and out of the lungs to continuously replace the gasses in the alveoli with those in the atmosphere
Inspiration
active process driven by the contraction of the diaphragm