Module 16: Respiratory System Flashcards
What are the two tracts the respiratory system is divided into?
The upper respiratory tract and the lower respiratory tract
The upper respiratory tract consist of structures located where
Outside the thoracic cavity
The lower respiratory tract consist of structures located where?
Inside the thoracic cavity
The upper respiratory tract consists of what structures?
Nose Nasopharynx Oropharynx Laryngopharynx Larynx
The lower respiratory tract consists of what structures?
Trachea, bronchi, and lungs
What are the functions of the structures of the upper respiratory tract?
Warm and humidifier inspired air
Senses of smell and taste
Chewing and swallowing food
Air enters and leaves the respiratory system through
The nose
What is the role of the cilia which is located inside the nostrils?
Filter out dust and large foreign particles
What bony structure separates the mouth from the nasal cavity?
The palate
What separates the nasal cavity into two halves?
Septum
The cavity is lined with epithelium rich in what type of cells that produce mucus?
Goblet cells
What is the role of the three conchae bones?
Create narrow passages, ensuring that most air contacts the mucous membrane on the way through.
As it does, the air picks up moisture and heat from the mucosa. At the same time, dust sticks to that mucus, which is then swallowed
What are the branches of the olfactory nerve responsible for?
The sense of smell
What is the role of the sinuses?
Drain mucus into the nasal cavity
What are the three regions the pharynx divides into?
- Nasopharynx
- Oropharynx
- Laryngopharynx
Which part of the three regions of the pharynx only allows air to pass through?
Nasopharynx
What two regions allow food in the air to pass through?
Oropharynx and laryngopharynx
What are the three functions of the larynx?
- Prevents food and liquids from entering the trachea
- Acts as an air passageway between the pharynx and the trachea
- Produces sound
What keeps the larynx from collapsing?
9 pieces of cartilage that form the larynx
What is the role of the epiglottis during swallowing?
Closes over the top of the larynx to direct food and liquids into the esophagus
What is the glottis?
The opening between the vocal cords
Where is the trachea found?
Lies just in front of the esophagus
What encircles and reinforces the trachea to keep it from collapsing?
C-shaped rings of cartilage
The trachea extends from the larynx to a cartilaginous ridge called
The carina (fork in the road)
Which lung is where most aspirated food particles or small objects are likely to get lodged?
Right bronchus (slightly wider and more vertical then left)
What are the primary structures for gas exchange in the lungs?
Alveolar sacs (clusters of alveoli)
The long passages all exist to serve the alveoli, why?
Because it’s within the alveoli that gas exchange occurs
What allows for efficient gas exchange between the capillaries and the alveoli?
The thin walls of the alveoli and the closeness of capillaries
Through which membrane does the exchange of air occur?
Respiratory membrane
What is the role of surfactant?
A substance that helps reduce surface tension to keep the alveolus from collapsing as air moves in and out during respiration
The primary bronchi and pulmonary blood vessels enter each lung through an opening on the lungs medial surface called
Hilum
Where is the apex of each long found?
Extends about 1/2” above the first rib
Where is the base of each long found?
Rests on the diaphragm
How many lobes are found in the right lung, and what are the lobes?
3 lobes - superior, middle, inferior
How many lobes are found in the left lung, and what are the lobes?
2 lobes - superior and inferior
What is the visceral pleura, and where is it located?
A serous membrane - Covers the surface of the lungs, extending into the fissures
(Attached to actual lungs)
Where is the parietal pleura located?
Lines the thoracic cavity
Where is the pleural cavity located?
The space between the visceral and parietal pleurae
*What are the two main roles of the serous fluid in the pleural cavity?
- Lubricates the pleural surfaces, allowing the two surfaces to glide painlessly against each other as the lungs expand and contract
- Creates a pressure gradient that assists in lung inflation
What is pulmonary ventilation?
Breathing - inhaling and exhaling
Inspiration and expiration both depend on what?
- Respiratory muscles
- Difference between air pressure within the lungs and outside the body
What is the main muscle used for pulmonary ventilation?
Diaphragm
What happens to the external and internal intercostal muscles and the diaphragm during inspiration?
External intercostal muscles - Pull the ribs up and out, widening the thoracic cavity
Internal intercostal muscles - Help elevate the ribs
Diaphragm - Contracts, flattens, and drops, pressing the abdominal organs down and enlarging and the thoracic cavity
What happens to the internal intercostal muscles and the diaphragm during expiration?
Internal intercostal muscles – pull the ribs down as external intercostals relax
Diaphragm - Relaxes, bulging upward and pressing against the base of the lungs, reducing the size of the thoracic cavity
During times of forced or laboured breathing (i.e. asthma attack), what muscles assist with breathing?
Accessory muscles
During deep inspiration, what happens to the accessory muscles?
Muscles of the neck (sternocleidomastoids and scalenes) and the chest (pectoral is minor) contract to help elevate the chest
During forced expiration – such as when singing or shouting – what happens to the accessory muscles?
The rectus abdominis and external abdominal obliques contract to pull down the ribs and sternum, further reducing chest size and expelling air more rapidly
The respiratory centers responsible for automatic, unconscious breathing reside where?
In the medulla and pons (parts of the brainstem)
What is the primary respiratory centre and where does it reside?
Inspiratory center - medulla
What is the expiratory centre used for, and where does it reside?
Used for forceful exhalations – Medulla
The apneustic center which reside in the pons, are responsible for?
Increases length and depth of inspiration
The pneumotaxic center in the pons is responsible for?
Prevents lung overinflation
Is carbon dioxide or oxygen the primary regulator of respiration? And why?
Carbon dioxide, because it easily crosses the blood-brain barrier
What signals respiratory centres about the body’s needs/Main chemical stimulus for breathing?
Sensory receptors throughout the body
What 5 factors influence breathing?
- Oxygen levels
- hydrogen ions (pH)
- Stretch
- Pain and emotion
- Irritants
What drives respiration?
Atmospheric pressure
What happens when air pressure with in the lungs drops lower than atmospheric pressure?
Air flows from the area of higher pressure – the air outside the body – to an area of lower pressure – the lungs; this is inspiration
What happens when air pressure within the lungs rises above atmospheric pressure?
Air flows out of the lungs (expiration) until the two pressures equalize
