Respiratory System Flashcards
What are the functions of the respiratory system
- gas exchange surface between air and blood
- move air to and from lungs
- protect respiratory surfaces from outside environments
- sound
- ppt in olfactory sense
What makes up the upper respiratory tract
Nose
Nasal cavity
Sinuses
Pharynx
What makes up the lower respiratory system
Larynx
Trachea
Bronchus
Bronchioles
Alveoli
How many times do the airways branch off down the bronchial tree
23
Each airway gives rise to two daughter airways
How far down the bronchial tree do alveoli appear
From branch 17
From what point is the whole airway alioli
From branch 20 onwards
Which lung is bigger
Right lung due to heart
How do the right and left lungs differ
Right lung is larger
Has 3 lobes
Left lung has 2 lobes
Cardiac knock to accommodate pericardial cavity
What are the features on the lateral surface of the lungs
Right:
Apex = top
Superior lobe
Middle lobe
Inferior lobe
Base
Left:
Apex = top
Superior lobe
NO middle
Inferior lobe
Oblique fissure (vertical)
Horizontal fissure (horizontal)
Base
Oblique fissure (vertical)
Horizontal fissure (horizontal)
What is the respiratory mucosa
The mucus membrane lining the conducting portion of the respiratory system
What does the respiratory mucosa consist of
Epithelial layer
Areolar layer
What is the name of the areolar layer of the respiratory mucosa
Lamina propria
How does the lamina propria differ in fit parts of the respiratory system
Upper respiratory system:
- contains mucus glands which secrete onto epithelial surfaces
Conducting portions of lower:
- contains smooth muscle
- at the bronchioles this forms circles around the lumen
How does the structure of respiratory epithelium change along the respiratory tract
Nasal cavity/superior pharynx:
- pseudostratified ciliated columnar with mucus cells
Inferior pharynx:
- stratified squamous
Superior portion of lower respiratory system:
- pseudostratified ciliated columnar
Smaller bronchioles:
- cuboidal epithelia with scattered cilia
Alveoli:
Simple squamous
What happens when things get trapped in mucus
Move upwards
Mucocillary escalator
Explain the passageway of air through the nose
- External nares (nostrils)
- Nasal vestibule (open space)
- Nasal meatuses; superior, middle, inferior (grooves between nasal conchae)
- Hard palate
- Soft palate
What does the hard palate firm
Floor of nasal cavity, separates from oral cavity
What does the soft palate do
Extends posterior to hard plate
Divides superior nasopharynx from lower pharynx a
What do the nasal measuses do
Warming and humidity
Swirling causes particles to touch mucus
What are the tree divisions of the pharynx
- Nasopharynx
- Oropharynx
- Laryngopharynx
What prevents food and liquid entering lower respiratory tract
Epiglottis
What is the epiglottis
Cartilage flap superior to the glottis
During swallowing, fold over the glottis to prevent entry
What is the larynx
Cartilage flap that surrounds the glottis
What controls sound variations
Larynx, change tension in cartilage
Tension on vocal folds
What produces sound
Air passing through glottis
Vibrates vocal folds
Produces sound waves
What are the two elements of speech
Phonation - sound produced at larynx
Articulation- modification of sound by other structures
Where does the trachea sit in relation to oesophagus
Oesophagus behind
What are the C shaped structures surrounding the trachea
Tracheal cartilages, strengthen but allow flexibility, protect
What is at the back of the trachea before the oesophageal
Trachialis muscle, can contract and constrict to expel air more forcefully
What is the mediastinum
Area in middle of thoracic cavity between right and left pleural sacks
What separates the right and left bronchi
Internal ridge called the carina
What are the differences between the right and left primary bronchi
Right:
Larger, has to supply a larger lung and descends at a smaller angle
Where does each primary bronchus go
To grooves called the hilums on medial surfaces of the lungs
What are extra pulmonary and infra pulmonary bronchitis
Extra pulmonary- outside lungs, the primary bronchitis
Infra pulmonary- inside the lungs
Explain the branching of bronchi
Primary branch to secondary
(Lobar bronchi) - one goes to each lobe, right has 3, left 2
Secondary branch to tertiary
(Segmental) - supplies air to single bronchopulmonary segment
Right 10
Left 8/9
What happens to cartilage down the bronchial tree
Less cartilage, more smooth muscle
More smooth muscle = more control on restriction of airflow
How many bronchioles does one tertiary bronchi branch to
6500
Explain bronchiole structure
No cartilage, dominated by smooth muscle
Autonomic control regulates smooth muscle, control airflow and distribution of air in lungs
Explain autonomic control of bronchiole
Sympathetic stimulation;
Bronchodilation
Parasympathetic stimulation:
(Or histamine release, allergies)
Bronchoconstriction
What is external respiration
All processes exchanging gas with the environment
- pulmonary ventilation
- Gas diffusion
- storage and transport of gas
- the exchange of dissolved gas
What is internal respiration
Involved the uptake of o2 and production of co2 within cells
What is pulmonary ventilation
The physical movement of air in and out of the respiratory tract
Provides alveolar ventilation
“” the alveoli
What is boyles law
Defines the relationship between gas pressure and volume
Pressure = 1/volume
Pressure and volume are inversely proportionate
In a contained gas, external pressure forces molecules closer, movement of molecules exerts pressure on the container
What is intrapulmonary pressure
The pressure inside the respiratory tract, at the alveoli
What is intrapleural pressure
The pressure in the space between parietal and visceral plurae
What controls mechanics of breathing
Rcc in medulla oblongata
= contraction of diaphragm and intercostals
Explain the mechanics of breathing during inspiration at rest
Diaphragm contracts and moves down
Lower ribs rotate down horizontal plane
(1cm at rest)
External intercostals also move ribs up and out
Explain the mechanics of breathing during expiration at rest
Passive
Diaphragm and external intercostals relax
Elastic recoil
Explain active respiration mechanics of breathing
Explain the role of surfactant
Thin film of liquid lining the alveoli
Surface tension of this liquid causes passive recoil of alveoli
Due to attractions between liquid particles, pull back together
What muscles contract during active inspiration
Sternocleidomastoid
Scalenes
Pectoralis minor
External intercostals
Diaphragm
What muscles contract during active expiration
Internal intercostals
Rectus abdominals
External obliques
What is the other name for passive breathing
Eupnea
What is the other name for forced breathing
Hyperpnea
What is the equation for minute ventilation
The amount of air moved each minute
VE = F x VT
F(frequency breath/min)
VT (tidal volume)
What is the equation for alveolar ventilation
The volume of air moved minus the air that dosent make it to the alveoli
VA = F x (VT - VD)
VD( dead anatomical space)
What is FVC
Forced vital capacity
How much air can you get out from maximal expiration
What is FEV1
FVC in 1 second
What is forced expiratory ratio
FEV1/FVC
What is the comp of air at sea level
78.6
O 20.9
Co 0.04
Water vapour 0.05
