Respiratory System

What are the two zones of the respiratory system?

The respiratory zone (site of gas exchange) and the conducting zone (all other respiratory passageways).

What structures are included in the respiratory system?

Nose, nasal cavity, paranasal sinuses, pharynx, larynx, trachea, bronchi, and lungs.

What are alveoli?

Tiny air sacs in the lungs where gas exchange occurs.

What is the function of the nose?

Provides an airway for respiration; moistens, warms, filters, and cleans incoming air; provides resonance for speech; houses olfactory receptors.

What divides the nasal cavity?

The nasal septum.

What are the two types of mucous membranes in the nasal cavity?

Olfactory mucosa and respiratory mucosa.

What is the function of the pharynx?

Connects the nasal cavity and mouth to the larynx and esophagus.

What does the nasopharynx do?

Serves as an air passageway and contains the pharyngeal tonsil.

What are the three parts of the pharynx?

Nasopharynx, oropharynx, and laryngopharynx.

What does the larynx do?

Provides an open airway, routes food and air, and produces sound.

What is the epiglottis's function?

Closes off the larynx during swallowing.

What is the glottis?

The vocal folds and the space between them.

What is the trachea also known as?

The windpipe.

What keeps the trachea from collapsing?

C-shaped cartilaginous rings.

What is the primary function of bronchi?

Conduct air into the lungs and branch into smaller airways.

What comprises the conducting zone?

Primary bronchi, secondary bronchi, tertiary bronchi, and bronchioles.

What is surfactant and where is it produced?

A substance that reduces surface tension in the alveoli, produced by type II alveolar cells.

What does the pleurae do?

Forms a double-layered serosa covering the lungs and thoracic cavity.

What is the function of the diaphragm during quiet inspiration?

Contracts to increase thoracic volume, decreasing intrapulmonary pressure.

What is Boyle's law?

At constant temperature, the pressure of a gas varies inversely with its volume.

What causes quiet expiration?

Passive process, primarily due to the elastic recoil of the lungs.

What is the residual volume?

The amount of air remaining in the lungs after maximal forced expiration.

What are the factors influencing tidal volume?

Body size, age, gender, and physical condition.

What is ventilation-perfusion coupling?

Ensures a close match between gas reaching the alveoli and blood flow in pulmonary capillaries.

What role does carbon dioxide play in respiratory control?

Increasing CO2 levels stimulate breathing rate and depth.

What are chronic obstructive pulmonary diseases?

Conditions like emphysema and chronic bronchitis characterized by obstructed airflow.

What is asthma?

A condition characterized by inflammation of the airways, leading to difficulty in breathing.

What is the Haldane effect?

Encourages CO2 exchange; more CO2 is carried in blood when oxygen saturation is low.

What is internal respiration?

Gas exchange between the blood and tissues, involving O2 uptake and CO2 unloading.

What is external respiration?

Gas exchange that occurs in the lungs, involving O2 uptake and CO2 unloading from blood.

What are the basic properties of gases related to respiration?

Dalton’s law of partial pressures and Henry’s law.

What is the trachealis muscle's function?

Decreases the trachea’s diameter during contraction.

How does temperature affect hemoglobin saturation?

Increased temperature leads to decreased affinity of hemoglobin for oxygen.

What is total lung capacity?

The sum of all lung volumes.

What is a spirometer used for?

Evaluating respiratory function and diagnosing conditions.

What is the most common malignancy strongly correlated with smoking?

Lung cancer.

How is oxygen primarily transported in the blood?

Mostly bound to hemoglobin, with a small amount dissolved in plasma.

What characterizes obstructive emphysema?

Permanently enlarged alveoli and deterioration of alveolar walls.

What adaptations occur at high altitudes?

Increased ventilation rate and production of erythropoietin.

What is the inspiratory reserve volume?

Amount of air that can be forcibly inspired beyond tidal volume.

What measures the pressures within the lungs compared to atmospheric pressure?

Intrapulmonary pressure.

What is the main neurotransmitter involved in regulating breathing?

Acetylcholine released by phrenic and intercostal nerves.

What is the principal function of the conducting zone?

To filter, warm, and moisten air before it reaches the alveoli.

What is the anatomical dead space?

Volume of the conducting zone conduits that doesn't contribute to gas exchange.

What is pulmonary ventilation?

The mechanical process of moving air in and out of the lungs.

How does the medulla oblongata regulate respiration?

Through dorsal and ventral respiratory groups that control rhythm.

What is the function of pulmonary capillaries?

Surround alveoli to facilitate gas exchange.

What is Type II alveolar cell's primary function?

Secreting surfactant to reduce surface tension in alveoli.

What happens to the diaphragm during forced expiration?

It relaxes, while abdominal muscles contract.

What occurs during hyperpnea?

Deep and vigorous respirations during exercise.

What can lead to chronic bronchitis?

Excessive mucus production and inflammation of lower respiratory mucosa.

What are the primary components of the respiratory membrane?

Type I alveolar cells and pulmonary capillary endothelial cells.

What is Valsalva's maneuver?

A behavior that involves closing the glottis to increase intra-abdominal pressure.

What is the role of the pneumonia?

Prevents overexpansion of the lungs by inhibiting inspiration.

What is the role of the sympathetic nervous system in respiration?

It causes bronchodilation, allowing easier airflow.

What happens to gas exchange efficiency when the respiratory membrane is thicker?

Gas exchange decreases due to longer diffusion distance.

What is acute mountain sickness?

Condition resulting from rapid ascent to high altitudes.

What is the primary stimulus for the central chemoreceptors?

Fluctuating levels of CO2 in the cerebrospinal fluid.

What is the function of the ventilatory control centers in pons?

Modification of breathing rhythm and prevention of overinflation.

What is the significance of the medial space between the vocal folds?

It is called the glottis.

What shared function does the oropharynx have?

Air and food passageway.

What characterizes restrictive pulmonary disorders?

Limited lung expansion and low vital capacity.

What happens to the vocal folds during sound production?

They vibrate as air passes over them.

What is the average tidal volume in a resting adult?

About 500 ml per breath.

What is the primary purpose of the pleural fluid?

To lubricate the pleural surfaces for frictionless movement.

What happens to intrapleural pressure during inspiration?

It becomes more negative, aiding lung expansion.

What is a characteristic of small cell carcinoma?

Rapid metastasis and clusters within the mediastinum.

What is the composition of alveolar gas different from atmospheric gas?

Due to gas exchange, humidification, and mixing.

What is an effect of chronic inflammation on lung compliance?

It decreases lung resilience and compliance.

What happens during prolonged or vigorous exercise?

Hyperpnea occurs to meet oxygen demands.

What role does the limbic system play in respiration?

It can alter the respiratory rate and depth during strong emotions.

What difference in gas exchange occurs in internal respiration?

Oxygen diffuses into tissues, while CO2 diffuses into blood.

What is a common diagnostic tool for respiratory function?

Spirometer.

What is the significance of bronchial arteries?

They supply systemic blood to lung tissue.

What is the importance of bronchioles in the conducting zone?

They significantly increase smooth muscle and regulate airflow resistance.

How do pulmonary irritant reflexes protect the lungs?

By causing bronchoconstriction in response to irritants.

What do type II alveolar cells secrete and why is it important?

Surfactant, which reduces surface tension and prevents alveolar collapse.

What is the role of the thoracic cavity during breathing?

It changes volume to facilitate airflow in and out of the lungs.

What physiological mechanism allows for increased blood flow to well-ventilated areas of the lungs?

Bronchial dilation in response to low CO2 levels.

What occurs when a person holds their breath?

CO2 levels rise, eventually stimulating the urge to breathe.

What is the primary risk factor for developing lung cancer?

Smoking.

What physiological changes occur in response to high altitude?

Increased ventilation rate, lower hemoglobin saturation, and erythropoietin production.

What influences the rate of oxygen unloading from hemoglobin?

Plasma partial pressure of oxygen and various physiological conditions.

What maintains the structural integrity of the bronchi and trachea?

C-shaped cartilaginous rings.

What is the main role of the respiratory mucosa?

To produce mucus for trapping pathogens and particles.

What role do central chemoreceptors play in respiration control?

They respond to changes in CO2 and H+ levels in blood. Be sure to read your notes thoroughly for further understanding!

What is Tidal Volume?

The amount of air inhaled or exhaled in a normal breath.

What is vital capacity equation?

VC = TV + IRV + ERV

What is total lung capacity equation?

TLC = TV + IRV + ERV + RV

What is the Functional Residual Capacity equation?

FRC = ERV + RV