Module 2- Respiratory System Flashcards
What are the lobes of the right and left lung?
R has three lobes- superior, middle and inferior. L has two lobes-superior and inferior. Asymmetry is due to the position of the heart.
Hilum
“Root” of the lung where the pulmonary vessels and bronchi enter into each lung
Lungs have _________ fissures throughout the lobes. Only the ________ lung has a horizontal fissure separating the superior and middle lobes.
Oblique, right
Visceral pleura
Directly covers the lungs
Parietal pleura
Covers the thoracic cavity as well as the rib cage, diaphragm, and mediastinum
Pleural space
Space between pleura, normally empty but can fill with air or fluid (pneumothorax/hemothorax)
What purposes do the pleura serve?
They reduce friction, provide a negative pressure environment required for lung expansion, and help pull the lungs open with the chest wall upon inhalation
Conducting portion of respiratory tract
Nasal cavities, pharynx (nasopharynx, oropharynx, laryngopharynx), larynx, trachea, paired bronchi, secondary and tertiary bronchioles
Filtration portion of respiratory tract
Nostrils: hairs, cilia, and mucous-producing goblet cells
Trachea and bronchi: cilia and mucous-producing goblet cells
Respiratory portion of respiratory tract
Respiratory bronchioles, alveolar ducts, alveolar sacs, alveoli
Nasal vestibule
Most external portion of the nasal cavity, just inside the nostrils
Nasal fossae
Nasal cavities separated by the septum
_________________ lines the nasal cavities and pharynx and protects these areas from frictional damage
Stratified squamous epithelium
What structures separate the nasal cavities from the mouth?
The hard palate and soft palate
Glottis
Opening into the larynx
Describe the process of swallowing
The larynx rises, and the epiglottis covers the trachea. The soft palate covers the nasal passages.
What structures form the interface between the conducting portion of the respiratory tract and the respiratory portion
Bronchioles
How many lobar bronchi are featured in the left and right lung?
2 and 3
What is the size threshold that divides the bronchi from the bronchioles?
1 mm
Respiratory bronchioles
Transitional zone in the respiratory tract concerned with both air conduction and gas exchange
Terminal bronchioles
Smallest air conducting bronchioles, come BEFORE the respiratory bronchioles
Alveoli
Tiny air pockets surrounded by capillaries that facilitate rapid gas exchange between oxygenated and deoxygenated blood
Histology
Study of the cellular anatomy of a tissue or organ that can be viewed through a microscope
Respiratory epithelium is composed of
Ciliated, pseudostratified columnar cells
Goblet cells
Produce mucous to trap debris which can be removed by the cilia
Stratified squamous epithelium can be found
In the beginning of the respiratory track, for example lining the nasal cavities
Simple squamous epithelium
One layer of flattened cells, lines the respiratory bronchioles
What are the three main functions of the respiratory tract
.1) Air conduction
2.) Air filtration
3.) Exchange of gases
Organization of descending respiratory anatomy
Trachea–>main bronchi (two each side)–> secondary bronchi (3 on right, two on left), tertiary bronchi, terminal bronchi (last air conducting bronchi, reach 1 mm), respiratory bronchioles, alveolar ducts, alveolar sacs, alveoli
Type 1 alveolar cells
Make up 95% of alveolar cells. Form the thin, simple squamous epithelium required for gas exchange in junction with capillaries
Type 2 alveolar cells
Make up 5% of alveolar cells. Secrete surfactant, possess stemless and differentiate into type 1 alveolar cells upon injury
Respiration includes the following steps:
1.) Breathing: inspiration (breathing air in) and expiration (breathing air out)
2.) External respiration: gas exchange with the environment at a respiratory surface
2.) Internal respiration: gas exchange between blood and tissue fluid
3.) Aerobic cellular respiration: production of ATP in cells
What three things are required for respiratory diffusion to be effective?
1.) moist
2.) thin
3.) large surface area in respect to the rest of the body
Describe the process of inhalation and exhalation
Upon inspiration, the ribs move superiorly and anteriorly, the diaphragm contracts and lowers, and air becomes less dense, creating a negative pressure environment which causes air to enter the lungs. During expiration, the ribs lower, the diaphragm relaxes and rises, and air becomes less dense, increasing intrathoracic pressure resulting in air leaving the lungs.
Incomplete ventilation
Not all air leaves the lungs upon expiration, helping to warm and moisten new air entering the lungs.
Describe the structure of hemoglobin
Four polypeptide chains each containing a heme group, can bind four molecules of O2
Carbaminohemoglobin
Hemoglobin bound to CO2, approximately 30% of CO2 is carried this way, the rest is soluble in blood as bicarb (converted by carbonic anhydrase)
Boyle’s Law
Pressure = 1/volume
Charles’s Law
Volume directly proportional to temperature
Dalton’s Law
Total pressure is equal to sum of partial pressures
Spirometer
Device used to empirically evaluate mechanics of ventilaltion
Tidal volume (TV)
Volume of air inhaled and exhaled during a cycle of quiet breathing, typically 500 mL
Inspiratory reserve volume (IRV)
Maximum amount of air able to be inhaled beyond normal inspiration, typically 3000 mL
Expiratory reserve volume (ERV)
Maximum amount of air able to be exhaled beyond normal expiration, typically 1200 mL
Residual volume (RV)
Amount of air remaining in lungs unable to be exhaled, typically 1300 mL
Vital capacity (VC)
ERV+TV+IRV, Expiratory reserve volume +tidal volume + inspiratory reserve volume
Total lung capacity (TLC)
Vital capacity (VC) + reserve volume (RV)
Inspiratory capacity
Tidal volume (TV) + inspiratory reserve volume (IRV)
Functional residual capacity
Reserve volume(RV) + expiratory reserve volume (ERV)
Minute volume
Amount of air moved through lungs
Emphysema
Damage to alveoli, inner walls of alveoli become weak and rupture
Cystic fibrosis
Mutation in chloride transporter results in thickened respiratory mucous (not enough saline in mucous, results in “clogs” and chronic infections
Pulmonary edema
Increased fluid in lungs, crackles
Pleurisy
Inflammation of the pleura (lining of the lungs) due to infection, cancer, or injury. In this condition, the pleural space fills up with air, pus, blood, or other fluids. Pleuritis causes sharp chest pain that worsens with breathing. The layers of the pleural cavity rub against each other creating friction. The increased fluid in the pleural cavity can make it difficult for a doctor to even hear a person’s heart sounds when auscultating their chest.
