Respiratory System Overview

Respiratory System

• Breath represents life, the first and last breaths are dramatic moments.
• Breathing is required for metabolism, as most metabolic processes require ATP. ATP production requires oxygen and generates carbon dioxide.
• The respiratory system's main function is to supply oxygen to the blood and eliminate carbon dioxide.
• The system consists of tubes delivering air to the lungs, where oxygen diffusion into the blood and carbon dioxide removal occur.
• The respiratory system has diverse functions including gas exchange, communication (speech), olfaction (smelling), regulating blood pressure and expelling abdominal contents.

Main Function of Respiration

• The respiratory system is an organ system specialized to provide oxygen to the blood and remove carbon dioxide.
• It plays a crucial role in diverse functions like gas exchange, communication and smell.
• Breathing, also called respiration, regulates blood pressure and expels abdominal contents upon command.

Conducting Zone (Upper and Lower Respiratory Tract)

• The nose, pharynx, larynx, trachea, and bronchi are part of the conducting zone.
• They only facilitate airflow and not gas exchange.
• The nose warms, filters and moistens air. The pharynx and larynx are common passageways for air and food. The trachea branches into bronchi, which further branch to form bronchioles.

Respiratory Zone

• The respiratory zone consists of bronchioles, alveolar ducts, alveolar sacs, and alveoli.
• Gas exchange with the blood occurs exclusively in the respiratory zone.
• Alveoli are microscopic air sacs where oxygen and carbon dioxide exchange with blood vessels.

Conducting and Respiratory Divisions

• The conduction division of the respiratory system involves the passages like the nose, pharynx, larynx, trachea, bronchi, and bronchioles.
• They serve for air passage, but gas exchange doesn't happen within these passages.
• The respiratory division contains the alveoli and related structures for gas exchange.

Nose

• The nose warms, cleanses, and humidifies inhaled air.
• The nose also detects odors in the air.
• It serves as a resonating chamber that amplifies the voice.
• The nose extends from a pair of nostrils to a pair of posterior nasal apertures (choanae).
• The nasal cavity is divided into right and left halves by the nasal septum.

Pharynx

• The pharynx is a muscular funnel extending from the nasal cavity and mouth to the larynx and esophagus.
• It serves as a common passageway for food and air.
• It has three regions: nasopharynx, oropharynx, and laryngopharynx.

Larynx

• The larynx is a cartilaginous chamber that keeps food and drink out of the airway but has a role in sound production.
• The larynx has three regions.
• The larynx is composed of nine cartilages including the epiglottis, thyroid, cricoid, etc.

Trachea and Bronchi

• The trachea (windpipe) is a tube with C-shaped cartilages preventing collapse.
• It lies anterior to the esophagus and conducts air to the lungs.
• The trachea splits into two main bronchi, each leading to a lung.
• Bronchus splits further into smaller bronchioles and into even smaller structures ending at alveoli.

Lungs

• Lungs are cone-shaped organs.
• Each lung has three faces: diaphragmatic, costal, and mediastinal.
• The mediastinal surface contains the hilum where the bronchi, blood vessels, and nerves enter/exit (lung root).
• The right lung has three lobes (superior, middle, inferior). The left lung has two lobes (superior, inferior).

Pleura

• The pleura is a double-layered membrane surrounding the lungs.
• The visceral pleura is layered against the lungs.
• the parietal pleura is layered against the thoracic cavity.
• A fluid-filled space exists between the layers for frictionless movement.

Root of the Lungs

• The root of the lung comprises the bronchus, blood vessels, nerves, and lymphatics.
• They enter and exit through the hilum.

Explore the functions and significance of the respiratory system in this quiz. Learn how it facilitates gas exchange, communication, and regulates various bodily processes. Discover the critical role breathing plays in maintaining life.