Lecture 13: Respiratory System Flashcards
What are the 4 main functions of the Respiratory System?
- Exchange of gas between the atmosphere and blood
- Filtration, temperature regulation and humidification
- Olfaction
- Production of sound
What is the dividing line between the upper and lower respiratory system?
The Larynx (vocal folds)
When we divide the respiratory system functionally, what are the two sections?
The Conducting portion and the Respiratory portion
What is the Conducting portion of the respiratory system?
The portion that is there to get air in and out
What occurs in the Respiration portion of the respiratory system?
Gas exchange occurs
What is the pathways that air takes in the upper respiratory system?
- External Nares
- Nasal Vestibule
- Conchae/Turbinates
- Internal Nares
- Nasopharynx
- Oropharynx
- Epiglottis
- Laryngopharynx
What is found in the Nasopharynx?
Adenoids and Eustachian tube
When does the Epiglottis close?
When you swallow
What is the function of the Turbinates in the nasal cavity?
Warm and moisten the air
What are the two ways the Oropharynx is protected when swallowing?
- The soft palate goes up
* The epiglottis goes up to the epiglottis
What is the Root (Hilum) of the lung?
The site where blood vessels, lymphatics, nerve and airways enter and leave lungs 🫁
How many lobes does the right lung have?
3 Lobes
How many lobes does the left lung have?
2
What fissure does the Left lung have?
The Oblique fissure that separates the superior and inferior
What are the fissures of the right lung?
Horizontal fissure and oblique fissure
What are the 3 lobes of the Right lung?
Superior, Inferior, Middle
What are the two Pleura?
Parietal Pleura and Visceral Pleura
What does the Parietal Pleura cover?
The inside of the body wall
What does the Visceral pleura cover?
The lung
What kind of membrane is the Pleura?
Mesothelium - A smooth epithelium layer
What is the Pleural Cavity?
The space between the visceral and parietal pleura
How many secondary bronchi are there in each lung?
3 on the right side
2 on the left side
What are the Terminal Bronchioles?
The last bronchioles of the conducting system
What is the shape of the cartilage around the esophogus?
A ring
Why is the ring of the trachea only a half cartilage ring?
Because the esophagus pushes up against it
What keeps the trachea as an open tube?
The cartilaginous rings around the trachea
How do we distinguish Bronchi from Bronchioles?
Bronchioles are only supported by smooth muscle and have no cartilaginous rings
Where does respiration happen?
In the alveoli
What is the purpose of the terminal bronchi?
To conduct air in and out
What are alveolar ducts?
The last tubes before you get to alveoli
What do Conducting airways do?
Warm moisten and conduct air
What do Respiratory airways do?
Conduct air and respire air
What are the 3 structures found in the Airway walls?
- Cartilage
- Smooth muscle
- Elastic fibers
Where is carilage found?
In larger airways
What is the function of cartilage?
To keep airways open
Where is smooth muscle mostly found?
In smaller airways
What is the function of smooth muscle in smaller airways?
Controls the diameter of the airway
Reduces airflow of the airway
Where are elastic fibers found in the airways?
In smaller airways and respiratory portion
What is the function of the elastic fibers?
Provides force for expiration through recoil
What occurs in an asthma attack?
Parasympathetic nerve stimulation causes smooth muscles to tighten and airways to be inflamed and thickened
What is Emphysema?
The breakdown of alveolar walls causing large air spaces which lowers space for gas exchange
What are some causes of Emphysema?
Smoking and other irritants: Pollution, dust
What type of cell is the majority of cells lining the Respiratory system?
Pseudostratified epithelium
Where is the Pseudostratified epithelium found?
- Nasal Cavity
- Nasopharynx
- Large airways
What is the function of Pseudostratified epithelium?
Has cilia and goblet cells that produce mucus
What is the sequence of thinning membranes as you move down the respiratory system?
- Simple Columnar
- Simple cuboidal
- Simple squamous
What is the type of tissue in the Oropharynx?
Stratified squamous non-keratinized because it also has to deal with food
What epithelium is in the alveoli?
Squamous epithelium: Type I alveolar cells
What cells form the wall of alveoli?
Type I epithelial cells
How do blood vessels maximize gas exchange?
They have blood vessels running between two alveoli
What is in between the Alveoli and the blood vessel?
The basement membrane
How many membrane does oxygen molecule need to pass through to get to the blood?
5
What is the function of Type II Alveolar Cells?
- Secrete Surfactant
* Are also stem cells for type I alveolar cells
What is the function of Surfactant?
Lowers surface tension of alveolar fluid
Prevents alveolar walls from sticking together and collapsing
What is the function of Alveolar Macrophages?
•Ingest debris in alveoli
How do macrophages in the lungs get taken away?
By mucus in the
How are macrophages in the lungs excreted?
They are carried toward the pharynx by ciliary action and expectorated or swallowed
What does the Pulmonary artery carry?
Deoxygenated blood
What does the pulmonary artery travel with?
The bronchi and branches whenever the bronchi branch
What do capillaries on the alveoli drain into?
The pulmonary vein
What do the Pulmonary veins carry?
Oxygenated blood
Where do Pulmonary veins and Lymphatics travel in?
The interlobular connective tissue
What blood vessels does gas exchange occur?
The alveolar capillaries
What muscles help with Quiet inhalation?
Contraction of External intercostals and the Diaphragm
What allows for quiet Exhalation?
Relaxation of external intercostals and diaphragm
What are the muscles of forced inhalation?
Scalenes Pectoralis minor Sternocleidomastoid External Intercostals Diaphragm
What are the muscles of forces exhalation?
Internal intercostal muscles
Abdominal wall muscles - compress viscera
What does the Sternocleidomastoid do?
Elevates the Sternum during force breathing
What do the Scalenes do?
Elevate ribs 1 and 2 during forces breathing
What does the Pectoralis minor do?
Elevates ribs 3-5 in force breathing
