Recording-2025-03-12T14:04:02.529Z

Introduction to the Pulmonary System

• Definition of Pulmonary: Relating to the lungs; understanding this helps to see its interaction with the cardiovascular system.

• Relationship: The pulmonary system and cardiovascular system work together to facilitate gas exchange in the body.

Importance of the Respiratory System

• Gas Exchange: All body cells use oxygen and release carbon dioxide continuously.

  • This process leads to the formation of deoxygenated blood, which returns to the heart.

• Reoxygenation: The heart pumps deoxygenated blood to the lungs for oxygenation.

• Consequences of System Failure: Failure of the cardiovascular or pulmonary system can lead to hypoxia (lack of adequate oxygen), resulting in rapid cell death.

• Dependency on Oxygen: Various tissues, such as nervous tissue, muscle, and epithelial tissue, rely heavily on oxygen supply.

Structure of the Respiratory System

External Respiratory Pathway

• Nostrils (Naress): Entry point for air; varies across species for functionality.

• Pharynx (Throat): Muscular tube serving both respiratory and digestive systems.

• Larynx (Voice Box): Comprised of cartilages aiding in sound production and protecting air passages.

  • Contains:

    • Thyroid Cartilage: Forms the Adam’s apple.

    • Epiglottis: Ensures food goes to the stomach, not the lungs.

    • Cricoid Cartilage: Provides structure under the thyroid cartilage.

Trachea and Bronchi

• Trachea (Windpipe): Tube structure transporting air to the lungs; made of hyaline cartilage to provide structural support.

• Bronchi:

  • Primary Bronchi: Branch off from the trachea into each lung.

  • Secondary Bronchi: Supply air to each lobe of the lung.

  • Tertiary Bronchi: Lead further into lung segments, leading to bronchioles and finally alveoli.

Classification of Respiratory Structures

• Upper vs Lower Respiratory System:

  • Upper: Nostrils, pharynx, and larynx.

  • Lower: Larynx, trachea, bronchi, and lungs.

• Infections:

  • Upper Respiratory Infection: Example: sinus infection.

  • Lower Respiratory Infection: Example: pneumonia.

Internal Nasal Structures

• Chambers: Large passages within the skull aiding air passage.

• Ethmoid Bone: Forms the roof of the nasal cavity.

• Nasal Septum: Separates the two nasal passages; can be compromised leading to a deviated septum.

Functions of Nasal Structures

• Olfactory Epithelium: Responsible for the sense of smell.

• Pseudostratified Ciliated Columnar Epithelium: Equipped with cilia to move mucus, which traps dust and debris, aiding in filtering air.

Bronchial Tree Structure

• Formation: Resembles a tree with trachea as the trunk and bronchi as branches.

• Changes in Tissue Type: Transition from pseudostratified columnar epithelium to simple squamous epithelium at the alveoli.

• Role of Smooth Muscle: Controls dilation/constriction of bronchioles in response to nervous system signals (ex: asthmatic reactions).

Lungs Anatomy

• Lobes:

  • Right lung: 3 lobes.

  • Left lung: 2 lobes (due to heart's position).

• Species Variations: Most livestock have an accessory lobe in their right lung.

Conclusion

• Importance of understanding the structure and function of the respiratory and pulmonary systems for overall health and functioning.

• Preparing for practical applications in anatomy and physiological responses.