lecture -2025-03-08T18:04:16.591Z

Lymphatic System Overview

• Thoracic Duct:

  • Drains lymph from the body except for the upper right corner (right arm and right side of the head).

  • Both legs and the left arm and head drain into the thoracic duct.

  • Right leg drainage leads to the thoracic duct.

• Subclavian Vein Relationship:

  • Thoracic duct dumps lymph into the left subclavian vein.

  • The right thoracic trunk drains into the right subclavian vein.

  • Importance of understanding the pathways in case of infections, affecting cross-communication.

Immune Response and Secretion

• Cell Secretion:

  • Cells secrete proteins but never other cells (e.g., no secretion of T cells or B cells).

  • Complement proteins are secreted by T and B cells to destroy viruses, not to relay warnings.

Respiratory Processes

• Types of Respiration:

  • External Respiration: Exchange of O2 and CO2 in the lungs.

  • Internal Respiration: Exchange of O2 and CO2 at the tissue level.

  • Gas Transport: Movement of gases throughout the body (not to be confused with gas exchange).

• Gas Laws:

  • P1V1 = P2V2: Relationship between pressure and volume during breathing.

    • Decreasing volume increases pressure; increasing volume decreases pressure.

  • Henry's Law: Higher concentration leads to greater solubility in fluids.

  • Dalton's Law (referenced as Thorn's law): Portion of total pressure contributed by each gas based on its concentration.

Factors Affecting Oxygen Transport

• Bohr Effect (not explicitly named):

  • Higher temperatures increase oxygen unloading from hemoglobin.

  • Oxygen is more readily released in warmer areas with higher metabolic demand (e.g., working muscles).

Lung Capacities and Volumes

• Functional Residual Capacity: Amount of air left in the lungs after passive exhalation.

• Inspiratory Reserve Volume: Additional air that can be inhaled after normal inhalation (tidal inhalation).

• Inspiratory Capacity: Total amount of air that can be inhaled after a tidal expiration, combining tidal volume and inspiratory reserve volume.

• Charts and Definitions:

  • Tidal Volume: Volume of air inhaled or exhaled in a normal breath.

  • Capacity vs. Volume Distinction: Capacities are combinations of two or more volumes.