Lab 7 Respiratory System

External nares: Also known as nostrils, these are the openings through which air enters the nasal cavity.

Nasal vestibule: This is the space inside the nostrils, lined with small hairs called vibrissae and mucous membranes. It helps to filter and humidify incoming air.

Nasal septum: The nasal septum is a partition that divides the nasal cavity into left and right sides. It is made up of cartilage and bone.

Nasal conchae (turbinates): These are bony projections within the nasal cavity covered in mucous membranes. They help to increase the surface area of the nasal cavity and assist in warming, humidifying, and filtering air as it passes through.

Olfactory region: This is located at the roof of the nasal cavity and is responsible for housing the olfactory epithelium, where olfactory receptors are located, allowing for the sense of smell.

Nasopharynx: The nasopharynx is the upper part of the throat behind the nose. It serves as a passage for air from the nasal cavity into the throat.

Oropharynx: The oropharynx is the middle part of the throat, located behind the mouth. It serves as a passage for both air from the nasopharynx and food from the mouth.

Laryngopharynx: This is the lowest part of the throat, situated behind the larynx (voice box). It serves as a common pathway for both air and food before they diverge into the trachea and esophagus, respectively.

Larynx (voice box): The larynx is a cartilaginous structure located in the neck, just below the pharynx. It houses the vocal cords and is responsible for producing sound, protecting the airway, and assisting in breathing.

Thyroid cartilage: This is the largest cartilage of the larynx and forms the prominent Adam's apple in the front of the neck.

Epiglottis: A flap of elastic cartilage located at the entrance of the larynx. During swallowing, it folds down to cover the glottis, preventing food and liquid from entering the trachea.

Trachea (windpipe): A flexible tube composed of cartilage rings, located anterior to the esophagus. It carries air from the larynx to the bronchi, providing a passage for airflow to and from the lungs.

Tracheal cartilage: These are C-shaped rings of hyaline cartilage that provide structural support to the trachea, preventing it from collapsing during inhalation.

Bronchi: The trachea divides into the right and left bronchi, which further branch into smaller bronchioles. These are the airways that carry air into the lungs.

Bronchioles: These are smaller branches of the bronchi within the lungs. They lack cartilage and are surrounded by smooth muscle, allowing for constriction and dilation to regulate airflow.

Alveoli: Tiny air sacs at the end of the bronchioles where gas exchange occurs. Oxygen from the air diffuses into the bloodstream, while carbon dioxide from the bloodstream diffuses into the alveoli to be exhaled.

Lungs: Paired organs located in the thoracic cavity, responsible for respiration. They contain bronchial tree structures and alveoli, facilitating the exchange of oxygen and carbon dioxide.

Diaphragm: A dome-shaped muscle located below the lungs and separating the thoracic cavity from the abdominal cavity. It plays a crucial role in breathing by contracting and relaxing to change the volume of the thoracic cavity, aiding in inhalation and exhalation.