12.1 Immune and Lymphatic System

• Fluid balance

• Fat absorption

• Immunity

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Lymphatic Function

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• Lymph nodes

• Lymphatic vessels

  • Valves​

• Capillaries

• Lymph Associated Organs/Tissues

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Structures

Filter Lymph

• 600 scattered around the body

  • palpable nodes

    • found just under the skin in the neck, under the arms, and in the groin area

• High concentration of lymphocytes

Drain lymph from tissues and deposit into veins

• Thin tubes that transport lymph fluid and lymphocytes throughout the body

  • Valves

    • unidirectional flow towards the heart

• larger than blood capillaries and smaller than venule

Drain lymph from tissues and deposit into veins

• Small vessels that transport lymphatic fluid (lymph) directly from the body's cells and tissues.

  • interweaved with blood capillaries

Composition

• Mostly water

• Chyle from the intestines

  • lipids and proteins

• Lymphocytes

• Damaged cells, cancer cells, and foreign particles (such as bacteria and viruses) that may have entered the tissue fluids

• Spleen

  • largest secondary lymphatic organ

• Thymus

  • the hormone stimulates T-cell production

• MALT (mucosa-associated lymphoid tissue)

  • ​tonsils

• GALT (gut-associated lymphoid tissue)

  • peyer's patches (intestines)

Lymphatic Associated Organs/tissues​

• White Pulp (WP)

  • primary immunologic region

    • T zone and B zone

      • House and regulate the adaptive immune response

    • Waste removal into splenic vein (Blood)

• Red Pulp

  • Degradation and recycling of RBCs

Spleen

• Fluid leaks out of blood capillaries or tissues

  • approximately 4 liters per day is deposited into the lymph system

• enters lymphatic capillaries

  fluid is now called lymph

• Transported by skeletal muscle contractions to Lymphatic ducts.

Lymph Flow

lymph that drains​ from the following structures

• right arm

• right side of the head

• right side of thorax ​

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​Right Lymphatic Duct

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Lymph that drains from the following structures

• legs

• abdominopelvic area

• left arm

• left side of the head

• thorax ​

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​Thoracic Duct

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