Respiratory System Overview

Respiratory System

• Breath is a vital aspect of life, exemplified by a baby's first breath and a dying person's last gasp.
• Breathing is crucial because most metabolic processes need ATP. ATP production requires oxygen and produces carbon dioxide.
• The respiratory system transports air, delivers oxygen to the blood, and removes carbon dioxide.
• The system is primarily made up of tubes that direct air to the lungs. Oxygen moves into the blood, and carbon dioxide is expelled.

Main Function of the Respiratory System

• The respiratory system provides oxygen for the blood and removes carbon dioxide.
• It's involved in numerous other functions, including communication (speech), sensing odors, regulating blood pressure, and expelling abdominal contents.

Parts and Function of the Respiratory Tract

• Upper Respiratory Tract:
  • Nose: warms, humidifies, cleanses air, detects odors, and amplifies voice. It has a vestibule (small dilated chamber). The nasal cavity's divided into nasal fossae with a nasal septum. It has 3 boney scrolls (conchae) which increase SA.
  • Pharynx: food and air passageway, divided into nasopharynx, oropharynx, and laryngopharynx.
  • Larynx: voice box, prevents food and drink from entering the airway, involved in sound production. Made up of several cartilages, including the thyroid cartilage (Adam's apple) and epiglottis.
• Lower Respiratory Tract:
  • Trachea: windpipe, supported by C-shaped rings of hyaline cartilage, carries air to the bronchi. Branches into main bronchus (primary bronchus).
  • Bronchi: branches of the trachea that carry air to bronchioles. These branch further into bronchioles, terminal and respiratory bronchioles, alveolar ducts, and sacs, ultimately to alveoli. Bronchi contain cartilage.
  • Lungs: organs of gas exchange. They are made by millions of alveoli. The hilum is the doorway where vessels and bronchi enter and exit lungs. They have lobes superior, middle, and inferior (right lung) and superior and inferior (left lung) .

Respiratory Processes

• Breathing (respiration): the process of inhaling and exhaling air.
• Inhalation: the act of drawing air into the lungs.
• Exhalation: the act of forcing air out of the lungs.
• External respiration: the exchange of gases between the alveoli and the blood.
• Internal respiration: the exchange of gases between the blood and body cells.

Structures for Gas Exchange

• Alveoli: tiny air sacs in the lungs where gas exchange occurs.
• Bronchioles: small tubes that carry air to the alveoli.
• Pleura: a double-layered membrane that surrounds the lungs. The visceral pleura surrounds the lung tissue. The parietal pleura lines the thoracic cavity. The fluid in the pleural cavity reduces friction during breathing. Inner and outer layers.

Larynx (Voice Box)

• The larynx plays a role in keeping food out of the airway and producing sound.

Pharynx (Throat)

• A muscular funnel that serves as the passageway for air, food, and drink. It's divided into 3 regions: nasopharynx, oropharynx, and laryngopharynx.

Bronchi and Bronchioles

• They branch systematically forming a bronchial tree to increase surface area for an efficient gas exchange. Cartilage is present in bronchi but eventually disappears in bronchioles.

Alveoli

• Microscopic structures that provide an expansive surface area for gas exchange, promoting rapid diffusion.

Lungs

• Essential organs for gas exchange. They have the hilum where the main bronchi, blood vessels, and lymph vessels enter and exit the lungs.

Pleura

• A two-layered serous membrane that surrounds the lungs, reducing friction during breathing.

Explore the essentials of the respiratory system, including its main functions and parts. Understand how it facilitates breathing, gas exchange, and its role in other bodily functions. This quiz will enhance your knowledge of the respiratory tract's anatomy and physiology.