Respiratory system Flashcards
→ functions of the system → anatomy of the system - nose to lungs → physiology of respiration
What are the primary functions of the respiratory system?
- Delivery of oxygen (O₂) to tissues.
- Removal of carbon dioxide (CO₂) from the body.
What are the secondary functions of the respiratory system?
- Thermoregulation (temperature control).
- pH regulation of body fluids (via CO₂ removal).
- Phonation (vocalization).
- Olfaction (sense of smell).
What is the planum of the nose?
A hairless region at the rostral part of the nose, kept moist by oily and mucus glands
How do horses’ nostrils differ from other species?
- Horses are obligate nasal breathers (cannot breathe through their mouths).
- They have flexible lateral nostrils.
What is the function of nasal cartilage?
It supports the nostrils and contributes to their size and shape variation among species
How does air travel through the nasal cavity?
- Air enters through the external nares (nostrils).
- Passes into the nasal cavity (which is above the oral cavity).
- Travels through dorsal and ventral air spaces.
- Exits via the internal nostrils (choanae) into the pharynx.
What are nasal conchae, and what do they do?
- Cartilaginous or ossified scroll-like structures covered with mucus membranes.
- Function to warm, humidify, and filter air before it reaches the lungs.
What special structure do pigs have in their nose?
A rostral bone, which helps with their rooting behaviour
What are the paranasal sinuses, and what is their function?
- They are air-filled extensions of the nasal cavity.
- Function to reduce head weight and provide thermal and mechanical protection.
What are the main paranasal sinuses?
- Frontal sinus.
- Maxillary sinus.
- Sphenopalatine sinus.
How are sinuses lined, and what problem can they cause?
- They are lined with a thin layer of respiratory mucosa.
- Infections in the sinuses can cause swelling and pain due to their proximity to teeth.
What is the pharynx, and what is its function?
- A common passageway for both the digestive and respiratory systems.
- Air passes through the pharynx before entering the trachea.
What is the larynx, and where is it located?
- It is the gateway to the trachea, suspended from the hyoid apparatus.
- Regulates airway size and protects the airway.
What are the main cartilages of the larynx?
- Unpaired cartilages:
- Cricoid cartilage.
- Thyroid cartilage (forms the base).
- Epiglottic cartilage (moves freely, prevents choking). - Paired cartilages:
- Arytenoid cartilages (dorsal part of the larynx).
- Cuneiform and corniculate processes (sometimes present).
What is the bronchial tree, and what are its divisions?
- Primary bronchi → enter lungs.
- Secondary bronchi → branch further inside lungs.
- Tertiary bronchi → smaller branches.
- Bronchioles → no longer supported by cartilage.
- Alveolar ducts → lead to alveoli.
Why is the trachea supported by cartilage rings?
To prevent collapse and allow for unobstructed airflow
What is the lining of the trachea?
Respiratory mucosa, with mucus-secreting glands to trap dust and microbes
What is a tracheal bronchus, and which species have it?
- A separate bronchus branching off before the main bronchi.
- Found in ruminants and pigs
What are the two pleural layers covering the lungs?
- Visceral pleura (inner layer covering the lungs).
- Parietal pleura (outer layer lining the thoracic cavity).
What is the function of pleural fluid?
Provides lubrication to reduce friction during breathing
What is the diaphragm, and what is its function?
- A muscular sheet that separates the thoracic and abdominal cavities.
- Main muscle of ventilation.
What is the hilus of the lung?
The entry point for bronchi, blood vessels, and nerves
What is the cardiac notch?
A space where the heart directly contacts the thoracic wall
What are alveoli, and what is their function?
Tiny air sacs covered in capillaries.
The primary site of gas exchange
