Respiratory System Flashcards
Pulmonary Ventilation
Process of air moving in and out of the lungs.
Boyles Law
Volume and pressure are inversely proportional.
Daltons Law
Each gas exerts a partial pressure. Total pressure is the sum of all partial pressures.
Henrys Law
The greater the partial pressure, the more soluble the gas is.
Inspiration
Respiratory Muscles- Contract
Volume- Increases
Pressure- Decreases
Air Flow- Inward
Expiration
Respiratory Muscles- Relax
Volume- Decreases
Pressure- Increases
Air Flow- Outward
Lung Volumes
TV- normal, quiet breathing
IRV- maximal inspiration
ERV- maximal expiration
RV- non moveable air, keeps airway open
Lung Capacities
VC- sum of all moveable air (TV+IRV+ERV)
TLC- sum of all lung volumes (TV+IRV+EV+RV)
Factors that Affect Pulmonary Ventilation
Increases resistance= low air flow
Increased surface tension= alveolar collapse
Decreased compliance= poor ventilation
Factors that increase breating rate and depth
Cerebrum (voluntary)
Hypothalamus (involuntary)
Chemoreceptors (02, Co2, pH)
Proprioceptors (movement/ exercise)
Factors that decrease breathing rate and depth
Cerebrum (voluntary)
Hypothalamus (involuntary)
Stretch receptors
Irritant receptors
External Respiration
process of breathing, which involves inhaling oxygen and exhaling CO2.
Internal Respiration
process by which 02 and CO2 are exchanged between blood and cells of the body.
Factors that affect partial pressure gradients (Daltons Law)
Ex Resp- PO2 greater in alveoli than in bloodstream, O2 enters bloodstream. PCO2 greater in bloodstream than in alveoli, CO2 leaves bloodstream and enters alveoli to be exhaled.
Int Resp- PO2 greater in BS than in tissues. O2 leaves BS and enters tissues. PCO2 greater in tissues than in BS, CO2 enters BS.
Factors that affect Gas Solubility (Henrys Law)
O2 relies on steep partial pressure gradients to diffuse across membranes.
Factors that affect Ventilation-Perfusion Coupling
EX RESP
If ventilation goes down… perfusion also needs to go down. Pulmonary arterioles need to constrict.
If ventilation goes up… perfusion also needs to go up. Pulmonary arterioles need to dilate.
Factors that affect Respiratory Membrane Structure
EX RESP
Low thickness and high surface area maximize gas exchange.
Gas Transport
the process by which oxygen is taken from inhaled air in the lungs and transported into the bloodstream
Oxygen Transport
the process where inhaled oxygen moves from the lungs into the bloodstream, primarily by binding to the protein hemoglobin within red blood cells, and is then carried throughout the body to tissues where it is released for cellular use
In Oxygen Transport <2% of O2 will…
dissolve directly into plasma
In Oxygen Transport >98% of O2 will…
bind to the iron in heme portion of hgb
O2-HGB Saturation Curve
% of 02 binding HGB
Factors that affect 02-HGB binding
Po2- 02 is released from HGB in areas of low po2
PCO2- 02 is released from HGB in areas of high PCO2
pH- 02 is released from HGB in areas of low pH
Temp- 02 is released from HGB at high temps
Carbon Dioxide Transport
carbon dioxide is transported from tissues throughout the body to the lungs primarily as bicarbonate ions within the bloodstream, where it is then diffused into the alveoli and exhaled, with a small portion carried dissolved in plasma and bound to hemoglobin within red blood cells
In CO2 transport 7% of CO2 will…
dissolve directly into plasma
In CO2 transport 23% of CO2 will…
bind globin portion of HGB
In CO2 transport 70% of CO2 will…
go through chem reaction that produces H+ and HCO3
In CO2 transport at the tissue level
-Cells make CO2 and load it into bloodstream
In CO2 transport at the lung level
-CO2 loaded in BS undergoes external respiration
Hypercapnia
-caused by hypoventilation
-elevated CO2 drives reaction forward and causes respiratory acidosis
Hypocapnia
-caused by hyperventilation
-low CO2 drives reverse reaction and causes respiratory alkalosis
Nasal Cavity: Gross Anatomy
-Nasal vestibule contains vibrissae (nose hairs) that filter out large particles
-Olfactory nerves provide sense of smell
-Nasal conchae are lined with respiratory mucosa that warms (thanks to blood vessels) &
humidifies air (thanks to mucus)
Nasal Cavity: Microscopic Anatomy
Pseudostratified ciliated with goblet cells
-Goblet cells produce mucus
-Cilia sweep
Pharynx: Gross Anatomy
-Nasopharynx has uvula that raises to seal nasal cavity while swallowing
-Oropharynx is where respiratory and digestive tracts converge
-Laryngopharynx is where respiratory and digestive tracts diverge
Pharynx: Microscopic Anatomy
Nasopharynx - Pseudostratified ciliated with goblet cells
-Oropharynx – Stratified squamous
-Laryngopharynx – Stratified squamous
Larynx: Gross Anatomy
- Contains hyaline cartilage for structural support
- Epiglottis is composed of elastic cartilage that covers the glottis while swallowing
- Glottis is the hole that allows air to pass through
- Vocal folds are vocal cords that vibrate to produce sound
Larynx: Microscopic Anatomy
Pseudostratified ciliated with goblet cells
Trachea: Gross Anatomy
-C-shaped cartilage rings are rigid enough to resist airway collapse but also flexible enough to accommodate increased respiration and forceful coughing
-Trachealis muscle allows for forceful breathing/ coughing
Trachea: Microscopic Anatomy
Mucosa: Pseudostratified ciliated with goblet cells
Submucosa: Seromucous glands
Adventitia: Hyaline cartilage
Bronchial Tree: Gross Anatomy
- Primary bronchi
- Lobar bronchi
- Segmental bronchi
- Bronchioles
- Terminal bronchioles
- Respiratory bronchioles have alveolar ducts that lead to alveolar sacs
Bronchial Tree: Microscopic Anatomy
-Cartilage content decreases.
- Pseudostratified transitions to simple cuboidal epithelium to simple squamous epithelium
- Cilia becomes sparse and goblet cells eventually disappear
- As cartilage content decreases, smooth muscle content increases.
Lungs: Gross Anatomy
-Surrounded by pleural membranes
-Right lung is larger and has 3 lobes
-Left lung is smaller and has 2 lobes and a cardiac notch
Lungs: Microscopic Anatomy
Type I cells are simple squamous cells that form alveolar walls
Type II cells secrete surfactant to prevent alveolar collapse
Alveolar macrophages are phagocytic
The Respiratory Membrane
- Fusion between alveolar and pulmonary capillary walls
- Function: Site for gas exchange
- Special Features:
Low thickness for easy gas diffusion
High surface area to maximize gas exchange
4 events of Respiratory Physiology
1.Pulmonary Ventilation
2.External Respiration
3.Gas Transport
4.Internal Respiration
