Exam 3: 6. Respiratory System

What is the primary function of the respiratory system?

Gas exchange: Oxygen enters the body while carbon dioxide exits.

What are the two main parts of the respiratory system?

Upper Respiratory System and Lower Respiratory System.

What does the upper respiratory system include?

Nose, nasal cavity, paranasal sinuses, and pharynx.

What is the function of the nasal cavity?

Filters, warms, and humidifies incoming air.

What is the role of the diaphragm in respiration?

It activates to facilitate inhalation and exhalation.

What is the conducting portion of the respiratory tract?

It carries air from the nose/mouth to the bronchioles.

What is the respiratory portion of the respiratory tract?

It is the site of gas exchange, including respiratory bronchioles and alveoli.

What is the function of the pharynx?

Conducts air and serves as a shared passage for air and food.

What are the three regions of the pharynx?

Nasopharynx, oropharynx, and laryngopharynx.

What is the role of the larynx?

Maintains an open airway and protects the airway during swallowing.

What are the vocal cords?

Structures located inside the larynx that vibrate to produce sound.

What is the trachea reinforced with?

20 C-shaped cartilage rings to prevent collapse.

What is the bronchial tree?

A branching system of airways that includes primary, secondary, and tertiary bronchi.

What is the function of the pleural membrane?

It lines the chest wall and covers the lungs, reducing friction during breathing.

What is the purpose of pleural fluid?

It reduces friction and helps the lungs adhere to the chest wall.

What happens during a pneumothorax?

Air enters the pleural cavity, disrupting negative pressure and causing lung collapse.

What is cellular respiration?

The process that converts glucose and oxygen into carbon dioxide, water, and energy (ATP).

What is the role of ATP in the body?

It fuels muscle activity, brain function, and all bodily processes.

What type of epithelium lines the conducting portion of the respiratory tract?

Pseudostratified ciliated columnar epithelium with goblet cells.

What is the function of the smooth muscle in the bronchial tree?

It controls the airway diameter.

What are the key structures of the larynx?

Epiglottis, thyroid cartilage, cricoid cartilage, arytenoid, corniculate, and cuneiform cartilages.

What is the significance of the epiglottis?

It closes during swallowing to protect the airway.

What is the primary function of the alveoli?

Gas exchange occurs here, transferring oxygen to blood and removing carbon dioxide.

How does the respiratory system help regulate blood pressure?

By maintaining carbon dioxide levels, which influence blood pH and volume.

What is the role of the tonsils in the pharynx?

They protect the lower respiratory system by trapping debris and pathogens.

What type of epithelium lines the upper airways?

Pseudostratified columnar, ciliated epithelium for mucus clearance.

How does the epithelium change in smaller airways?

It transitions to simple ciliated columnar or cuboidal epithelium, with fewer ciliated cells.

Where are goblet cells most abundant in the respiratory system?

In the trachea, but they decrease in number as airways narrow and are absent in tertiary and terminal bronchioles.

What is the function of the lamina propria in the respiratory system?

It supports the epithelium with fibroelastic connective tissue and contains immune cells.

What types of immune cells are found in the lamina propria?

Lymphocytes, plasma cells, mast cells, and eosinophils.

What role does smooth muscle play in the respiratory system?

It allows for bronchoconstriction and dilation and becomes more prominent as airways narrow.

What is the purpose of cartilage in the respiratory system?

It provides structural support to keep airways open, diminishing in prominence as airways narrow.

What are ciliated cells responsible for in the conducting portion of the airways?

They move mucus and trapped debris out of the airways.

What are Clara (club) cells and their function?

Non-ciliated dome-shaped cells that secrete surface-active agents to prevent airway collapse and contribute to repair and detoxification.

What is the significance of the transition from conducting to respiratory bronchioles?

Gas exchange begins as the walls contain alveolar openings.

What type of cells cover 95% of the alveolar surface?

Type I pneumocytes, which facilitate gas exchange.

What is the function of Type II pneumocytes?

They produce surfactant, reducing surface tension and preventing alveolar collapse.

What role do alveolar macrophages play in the lungs?

They patrol alveoli, removing debris, pathogens, and dead cells to prevent infections.

What are alveolar pores and their function?

They connect neighboring alveoli, allowing airflow between them and equalizing air pressure.

What is the respiratory membrane?

The blood-air barrier formed by the alveolar cell layer, fused basal laminae, and capillary endothelial cells.

What is Respiratory Distress Syndrome (RDS) and its cause?

A condition in premature infants caused by a deficiency in surfactant, leading to alveolar collapse.

What is the function of pulmonary arteries?

They carry deoxygenated blood from the right ventricle to the lungs.

What is a pulmonary embolism (PE)?

A blockage by a blood clot, fat embolism, or air bubble that can lead to severe respiratory distress.

What do bronchial arteries supply?

Oxygenated blood to the conducting portions of the lower respiratory system.

How do bronchial veins affect oxygen concentration in pulmonary veins?

They drain into pulmonary veins, diluting oxygen concentration before blood reaches the left atrium.

What is the effect of the parasympathetic nervous system on the lungs?

It causes bronchoconstriction and increased mucus secretion.

What is the effect of the sympathetic nervous system on the lungs?

It causes bronchodilation and decreases mucus production.

What is the role of brush cells in the respiratory system?

Specialized epithelial cells with microvilli that function as chemosensory cells.

What happens to goblet cells in terminal bronchioles?

They are absent to prevent mucus accumulation that could obstruct airflow.

What is the structure of alveolar ducts?

Lined by alveolar openings, forming a passageway to alveolar sacs, with simple squamous epithelium.

What is the significance of the capillary network surrounding alveoli?

It improves gas exchange efficiency by allowing for rapid diffusion of gases.