Respiratory System Flashcards
What are the steps of Respiration?
- Ventilation (moving air into and out of the lungs)
- Gas exchange -> air <-> blood
- Gas Transport
- Gas exchange -> Blood <-> cells
- Cellular Respiration (using O2, making CO2)
Components of the respiratory system
- Nasal Cavity/ Mouth
- Pharynx
- Larynx
- Trachea
- Right and Left main bronchus
- Right and Left Lungs
(within lungs, lobar bronchi, bronchioles)
Diaphragm - contraction expands lungs. Decrease lung pressure, allows air to flow in.
What is the order, and what are the zones?
(Conducting Zone) - No gas exchange, just passing air through
Trachea -> Bronchi -> Bronchioles -> Terminal Bronchioles
(Respiratory Zone) - Gas exchange
Respiratory Bronchioles -> Alveolar Ducts -> Alveolar Sacs
Features of the alveoli
Ciliated Columnar Epithelium - For cleaning, called the mucocilliary ladder
Alveoli - Air space, simple squamous Epithelium (type 1 cell)
Type 2 cell - Produce surfactant
Capillary Nedothelium
Interstitium - connective tissue
Damage to the alveoli
Scar tissue surrounding the large sacks in Emphysema
Normal alveoli looks like big round sacks
Structure of the pleural sac?
Totally enclosed around the lung.
Visceral Pleura - adhered to lung surface
Parietal Pleura - Adhered to chest wall and diaphragm
Pleural Cavity - filled with pleural fluid
Purpose is to decrease friction
How does pleural sac help maintain lung expansion
Pressure? (see slide)
What is the mechanism of inhalation
Diaphragm contracts -> Thorax expands -> Thoracic cavity and parietal pleura -> Pressure of intrapleural fluid more subatmospheric -> Lungs expand (Visceral pleura) -> Pressure of alveoli becomes subatmospheric -> Air flows into alveoli
Mechanism of exhalation
Diaphragm stops contracting -> Chest wall recoils back to normal -> Interpleural pressure moves back to normal -> Lungs recoil back to normal -> alveolar pressure goes back to normal -> air flows out of the lungs
What do these respiratory volumes reveal about lung function?
- Tidal volume - volume moved in quiet respiration
- Inspiratory reserve volume - breathing in beyond normal
- Expiratory reserve volume - additional volume moved in forced exhalation
TV + ERV = Forced expiratory volume - Residual Volume - minimum volume of air that fills alveoli and airways
- Vital Capacity - Max we can move in and out of our lungs TV + IRV + ERV
- Inspiratory capacity - TV + IRV
- Functional residual capacity - How much volume after an exhale - ERV + RV
- Total lung capacity - max amount of volume in our lungs VC + RV
Lung compliance
(see slide)
know the equation
- The pliability of lung tissue (how well does it stretch, and how well does it recoil)
Increased compliance - decrease recoil, hard to exhale (emphysema)
Decreased compliance - decrease stretchability, hard for lungs to expand, hard to inhale
How is surfactant produced, and how does it increase lung compliance
Surfactant - lipids and protein
produced by surfactant
breaks up the adhesion of H20 to cell. allows alveolar inflation
If surfactant isn’t present, causes alveolus to collapse
What influences the partial pressures of O2 and CO2 in the “blood plasma “
(see diagram)
- change of pressure because of residual volume
How quickly does arterial pressure of O2 change as the blood moves through pulmonary capillaries
(see diagram)
- comparing healthy alveolar Pressure vs diseased alveolar pressure
Structures and how they optimize RBC’s ability to carry oxygen throughout the body
Hemoglobin - 4 subunit protein, heme group (can take one oxygen)
binding one oxygen facilitates binding the next oxygens
RBC’s are dead at maturity -> 120 days in circulation
