Respiratory system ANATOMY

Overview: The nasopharynx is the uppermost part of the pharynx, located behind the nasal cavity. It plays a crucial role in respiration and connects the nasal cavity to the oropharynx. It contains structures like the adenoids and the opening of the auditory tube.
Adenoids:
- Also known as pharyngeal tonsils.
- Located on the roof of the nasopharynx.
- Enlargement (due to infection) can lead to:
  - Blockage of posterior nasal opening, causing mouth breathing and snoring.
  - Blockage of auditory tubes, causing middle ear infection (otitis media).
Auditory Tube:
- Also known as the Eustachian tube.
- Its opening is located in the nasopharynx.
- Blockage of the auditory tubes can cause middle ear infection (otitis media).
Mouth Breathing & Snoring:
- Can be caused by enlarged adenoids blocking the posterior nasal opening.
Middle Ear Infection:
- Can be caused by enlarged adenoids blocking the auditory tubes.

Overview: Sinusitis is a common condition, often a complication of nasal infections, characterized by the inflammation of the sinus lining. This inflammation leads to the closure of drainage pores, causing mucus buildup and pressure within the sinuses, resulting in sinus headaches.
Nasal Infections:
- Sinusitis is commonly triggered by nasal infections, such as viral or bacterial infections.
- These infections cause inflammation and swelling of the nasal passages and sinuses.
Irritation of Nasal Mucosa:
- Irritation of the nasal mucosa leads to inflammation and swelling.
- Swelling contributes to the narrowing or blockage of sinus drainage pathways.
Drainage Pores Closure:
- Inflammation causes the closure of the drainage pores of the sinuses.
- Blockage prevents mucus from draining properly, leading to accumulation in the sinuses.
Sinus Headaches:
- Mucus accumulation in the sinuses results in increased pressure.
- Increased pressure leads to sinus headaches, a common symptom of sinusitis.
- Sinus medication reduces swelling, allowing mucus to drain and alleviate headaches.

Overview: The trachea, or windpipe, is a tube that extends from the larynx to the main bronchi, providing a clear airway for air to enter and exit the lungs. It is characterized by its C-shaped cartilage rings and mucous membrane cilia.
C-shaped Cartilage Rings:
- Incomplete rings made of cartilage, fibrous tissue, and smooth muscle.
- Provide support and prevent trachea collapse, while allowing flexibility.
Mucous Membrane Cilia:
- Ciliated mucous epithelium lines the trachea.
- Cilia movement propels debris away from the lungs.
Carina:
- Located at the distal end of the trachea.
- Point where the trachea bifurcates into the left and right primary bronchi.
Bronchoscopy:
- Allows visualization of the trachea.
- Medical procedure to visualize the airways for diagnostic and therapeutic purposes.

Overview: The larynx, or voicebox, connects the pharynx to the trachea. It is composed of nine cartilages, including the thyroid and cricoid cartilages, and houses the vocal cords. It functions in voice production and prevents food and drink from entering the trachea.
Voicebox:
- Common name for the larynx.
- Located at the superior end of the trachea.
Cartilages:
- Composed of 9 pieces of cartilage
- Thyroid cartilage: 'Shield' shaped, Adam's apple
- Cricoid cartilage: Signet-ring shaped.
- Arytenoid cartilages: Pair of cartilages involved in vocal cord movement.
Epiglottis:
- Cartilage flap that closes off the larynx during swallowing.
- Prevents food and liquid from entering the trachea.
Vocal Cords:
- Also known as true vocal cords.
- Involved in voice production by vibrating as air passes over them.
- Tension can be changed to alter the pitch of the sound.
Rima Glottidis:
- The opening between the vocal cords.
- Size and shape change depending on vocal cord position.
Glottis:
- Anatomical term that constitutes the rima glottidis and vocal folds.
- Plays a key role in phonation.

Overview: The bronchi are the main passageways into the lungs, branching from the trachea. They have a similar structure to the trachea, including cilia, and divide into the right and left primary bronchi, which then further divide into secondary and tertiary bronchi.
Primary Bronchi:
The trachea divides into two main bronchi that enter the lungs.
These are the right and left primary bronchi.
Cilia:
The bronchi, like the trachea, are lined with cilia.
Cilia help to trap inhaled particles and move them up the airways away from the lungs.
Right Primary Bronchus:
Wider and more vertical compared to the left primary bronchus.
Due to its vertical orientation, inhaled objects are more likely to enter the right bronchus.
Left Primary Bronchus:
More horizontal in orientation compared to the right primary bronchus.
It is narrower than the right primary bronchus.

Overview: The nasal cavity is a large air-filled space above and behind the nose in the mid-face. It filters, warms, and moistens air entering the body, and contains the olfactory region for the sense of smell. The nasal cavity connects to several paranasal sinuses.
Ciliated Mucous Membrane:
- Lines the nasal cavity.
- Contains cilia that trap dust and move the mucus to be expectorated or swallowed.
Air Filtration:
- Nasal hairs filter air.
Air Warming:
- Occurs through contact with the mucous surface.
Air Moistening:
- Achieved by evaporation from the mucous membrane.
Nasal Septum:
- Divides the nasal cavity into two passages.
Oral Cavity:
- Separated from the nasal cavity by the hard and soft palates.
Cranial Cavity:
- The nasal cavity sits inferior to the cranial cavity.
Sphenoidal Sinus:
- One of the paranasal sinuses that connects to the nasal cavity.
Conchae:
- Superior, middle, and inferior conchae are bony projections that increase the surface area of the nasal cavity to help with warming and humidifying the air.
Meatus:
- Superior, middle, and inferior meatuses are nasal passages located beneath each corresponding concha.