Respiratory System Flashcards
1
Q
Upper Respiratory Tract (URT)
A
- Nose & nasal cavity - paranasal sinus
- Pharynx
- Larynx
2
Q
URT: Nose and Nasal Cavity functions
- What does it provide?
- What does it do to the incoming air?
- What does sinuses increase? And serve as?
A
- Provide an airway for ventilation
- Filters and cleans the incoming air
- Moistens and warms the incoming air
- Sinuses increase mucosal surface area, and also serve as resonating chambers for speech
- Sense of smell - houses olfactory receptors
3
Q
URT: Nose and Nasal Cavity functions
Nasal cavity features (8)
- Divided by what? - What is this made up of?
- What is posterior?
- What is on the roof?
- What is on the floor?
- What is on the lateral walls?
- What is the purpose of the structures?
A
- Divided in midline by nasal septum - hyaline cartilage (anterior) & bone (posterior)
- Posterior nasal aperture (nares) open into nasal pharynx
- Roof: ethmoid and sphenoid bones
- Floor: hard (anterior) and soft (posterior) palates
- On the lateral walls, there are three, mucosa-covered projections, the superior, middle, and inferior turbinates (conchae)
- These curved structures swirl the inspired air, so that heavier particles are deflected onto the mucosa
- The turbulence assist to clean the incoming air
4
Q
What are the three mucosa-covered projections on the lateral walls?
A
- Superior turbinate
- Middle turbinate
- Inferior turbinate
5
Q
URT: paranasal sinuses features (4)
- What is the group of sinuses (cavities) that surround the nose?
- What is the function of sinuses
- What do the sinuses allow
- What can mucous from the sinuses do>
A
- A group of sinuses (cavities) surround the nose - the frontal, sphenoid, ethmoid and maxillary sinuses
- Sinuses lighten the skull and help warm and moisten the incoming air
- Sinuses also allow sound resonance
- Mucous from the sinuses can block the drainage, and lead to a ‘sinus headache’
6
Q
URT: Pharynx (throat) features
- What type of tube is the pharynx?
- What does the pharynx connect?
- What regions the pharynx divided into?
A
Muscular tube (funnel-shaped) connects the;
- Nasal cavity to the oral cavity (mouth)
- Larynx and the esophagus
Divided into three regions
- The NASOPHARYNX, the OROPHARYNX and the LARYNGOPHARYNX
- Nasopharynx (above the soft palate) serves only as an air passage
7
Q
URT: Nasopharynx features (5)
- Location?
- Nasopharynx extends from?
- During swallowing, what happens?
- What drains into the nasopharynx?
- What happens when pharyngeal is infected?
A
- Posterior to nasal cavity
- Extends from the posterior nares to the soft palate
- During swallowing, the soft palate and the uvula swings posteriorly and superiorly, covering the nasopharynx, thus the nasal cavity
- The auditory tubes drain from the middle ear into the nasopharynx
- The posterior wall of the pharynx contains lymphoid tissue (pharyngeal tonsils or adenoids) - Infected pharyngeal can enlarge and restrict air flow = “adenoidal’ voice
8
Q
URT: Oropharynx features (6)
- Location of oropharynx?
- What passes through the oropharynx?
- What tissue does the oropharynx contain?
- Which one is commonly infected in children?
A
Posterior to the oral cavity and extending from the soft palate to the epiglottis
- Both food and air pass through the oropharynx
- Contains lymphoid tissue (palatine & lingual tonsils) - the palatine tonsils are commonly infected in children
- Epithelium changes in this region
- Stratified, squamous epithelium
- To prevent the throat from friction and chemical trauma during food ingestion
9
Q
URT: laryngopharynx features (3)
- Location of the laryngopharynx?
- Extends to?
- During swallowing?
A
- The laryngopharynx is the region inferior the epiglottis
- Extends to the level where the respiratory and digestive tract diverge
- During swallowing, food has the ‘right of way’ over air and breathing is paused
10
Q
URT: Larynx Features (4)
- What production?
- What does the larynx provide?
- Extends from?
- What protects and maintains an open airway?
- What does the larynx divert
A
- Sound/voice production
- Provides a patent airway - conducts air & protects the airway from collapse
- Extends from the region of the hyoid bone to level of the esophagus
- Nine cartilages protect and maintain an open airway
- Diverts air and food in proper directions (epiglottis)
11
Q
URT feature (2)
- What type of epithelium?
- What is the region called where only air?
A
- Regions where air and food pass = stratified (layered) squamous (flattened) epithelium
- Regions where air only = respiratory (mucosa)
12
Q
URT: Epithelium (‘cells’) features
- Nose
- What is the vestibule lined with?
- What is the purpose of hairs?
A
- Vestibule, lined with skin that contains sebacous and sweat glands, and hair follicles (=protection)
- The hairs (vibrissae) filter coarse particles (dust, lint, pollen, ash etc) from the inhaled air
13
Q
URT: Epithelium features (2)
- Location of the olfactory mucosa?
- what does it contain?
- What is the epithelium of the respiratory mucosa?
A
Olfactory mucosa
- Openings at the roof of the nasal cavity and contains sensory (smell) receptors (CN1)
Respiratory mucosa
- Pseudostratified, ciliated, columnar epithelium (containing goblet cells)
14
Q
URT: Warming the incoming air feature (3)
- What warms the incoming air?
- What happens if the inspired air temperature drops?
- Where do nose bleeds originate from?
A
- Underneath the respiratory epithelium lies a bed of thin-walled veins, which warm the incoming air
- If the inspired air temperature drop, the vascular plexus responds by dilating and becoming filled with more blood, thus intensifying the heat transfer
- Nose bleeds originate from these thin-walled veins, which are close to the surface
15
Q
URT: Runny nose features (2)
- What does the movement of cilia create?
- Why does your nose dribble (runny nose)?
A
- The movement of the cilia creates a slow moving current of mucus towards the pharynx, so that the contaminated mucus is swallowed and hydrolysed (digested) by stomach acid
- On a cold day the cilia in your nose ‘cool down’ and stop ‘beating’ - hence your nose dribbles = aka ‘runny nose’
16
Q
Regions of the lower respiratory tract (LRT)
A
- Trachea
- Bronchi
- Bronchioles
- Alveoli
17
Q
LRT: Trachea to alveoli functions
- What does it conduct?
- What does this process complete?
- Where does gas exchange occur?
A
- Conducts air to/from site of gas exchange
- Completes the cleaning, warming and humidification of inhaled air
- Gas exchange occurs at the alveolus (Pl. alveoli)
18
Q
LRT: Trachea functions
- What does the trachea maintain?
- What does cilia form? why?
A
- Maintain patent (open) airway for conduction of air
- cleans, warms and humidifies inhaled air
- Cilia form the mucociliary escalator to remove debris to the pharynx, and redirect to the stomach
19
Q
LRT: Trachea features (4)
- Trachea location?
- Where does the trachea extend?
- What epithelium is the trachea lined with?
- What shaped cartilages?
What muscle is posterior?
A
- Trachea is anterior to esophagus
- Rigid tube from larynx to primary bronchus
- Lined with respiratory mucosa (epithelium)
- “C” shaped cartilages
- Trachealis muscle posteriorly
20
Q
LRT: Brochial Tree arrangement
A
Trachea → 1* bronchi → 2* (lobar) bronchi → 3* (segmental) bronchi (>1mm) → Bronchioles (<1mm) → branching, branching…. → Terminal bronchioles (0.05mm)
21
Q
LRT: Primary bronchi
- Location?
A
- Located outside lungs
22
Q
LRT: Intrapulmonary bronchi features (3)
A
- 2* to each lobe
- 3* to each lobule (segment)
- Bronchioles
23
Q
LRT: Lung structure (5)
- Where is the lung situated?
- What region of the lung is apex?
- What region of the lung is base?
- Costal surface location?
- Hilum location?
A
- Right and left lungs are situated within two pleural cavities
- The ‘apex’ is superior region of a lung: near the clavicle
- The ‘base’ of a lung is inferior; sits on diaphram
- The costal surface - outer surface; against ribs
- The hilum - medial; structures enter/ exit
24
Q
LRT: Right & Left lung
- Amount of lobes and fissures
A
Left lung - 2 lobes - 1 fissure Right lung - 3 lobes - 2 fissures
25
Q
LRT: Blood-gas barrier features
A
- The lungs have a LARGE surface area for gas exchange
26
Q
LRT: Respiratory zone structure (2)
- What are the alveoli located in?
- Describe the walls of the alveoli
A
- Alveolar sacs are like bunches of grapes, containing many alveoli; the site of gas exchange
- The walls of the alveoli are very thin, a single layer of flattened epithelial cells with a thin basement membrane (aka the basal lamina)
27
Q
LRT: Alveolus structure (3)
- What covers alveolus surface?
- What are the lung epithelial cells?
- what type of epithelial cells are they?
- What reduces surface tension of the alveolar fluid?
A
- Dense capillary network covering the surface
- ‘Pneumocytes’ (lung epithelial cells)
- Type 1 pneumocytes (squamous; epithelial cells)
- Type 2 pneumocytes (cuboidal; surfactant-secreting cells)
- Type 2 cells scattered amongst the type 1 cells
- Surfactant is a complex lipoprotein (phospholipid) that reduces the surface tension of the alveolar fluid
28
Q
LRT: respiratory zone function (3)
- What is the external surface of the alveoli covered with?
- What forms the respiratory membrane (blood-air barrier)?
A
- The external surfaces of the alveoli are covered with a fine network of pulmonary capillaries
- The alveolar and capillary cell walls, and their joined basement membrane, form the respiratory membrane (aka the blood-air barrier)
29
Q
LRT: epithelium structure
- What type of epithelium?
- What glands are underneath the epithelium?
- What do these glands secrete?
- What does respiratory epithelial cells secrete?
A
- Respiratory mucosa (pseudo stratified, ciliated columnar epithelium, containing goblet cells) is present in most of the LRT
- Underneath the epithelium are mucous and serous glands (seromucous)
- Mucous cells secrete mucus, and serous cells secrete a watery fluid (seromucous) containing mucous & enzymes
- Respiratory epithelial cells secrete defensins, antibacterial/antifungal prions
30
Q
RT: Epithelial & Structural changes
- What occurs to epithelial cells as height changes?
- What happens to the cartilage support as the bronchi decrease in diameter?
- What is not found in the bronchioles or alveoli?
- What removes any inhaled debris that reaches the bronchioles or alveoli?
A
- Epithelial cells decrease in height
- Cartilage support decreases as the bronchi decrease in diameter
- No cilia, or mucous-secreting cells are found in the bronchioles or alveoli
- Macrophages remove any inhaled debris that reaches the bronchioles or alveoli
