Topic 13 - lymphatic system

What does the Lymphatic system include?

• lymph vessels + organs

• T & B lymphocytes

  • protect body against bacteria, viruses, cancer cells

What are the Major Extracellular Fluids

• Blood plasma

• ISF (Interstitial fluid)

• Lymph

What is Blood plasma?

fluid in blood

What does ISF(Interstitial fluid) do?

bathes cells (except blood cells)

Where is Lymph?

inside lymphatic vessels

What is part of the Lymphatic Circulation?

ISF (Interstitial Fluid and the Lymph

How is ISF (Interstitial Fluid) formed?

by capillaries leaking plasma

What happens with the 90% of ISF in the Lymphatic Circulation?

re-enters blood in capillaries + venules

What happens with the 10% of ISF in the Lymphatic Circulation?

goes into lymphatic circulation (now called lymph)

What happens in the Lymph part of the Lymphatic Circulation?

• enters lymphatic capillaries (closed ended vessels)

• lymphatic capillaries connect to lymphatic collecting vessels (have valves)

The Lymph nodes along vessels filter what?

The Lymph

• bacteria, debris

The lymph nodes along vessels filter lymph (bacteria, debris) and transport lymph fluid AWAY from tissues to

• Right Lymphatic Duct

• Thoracic Duct

What happens in the Right Lymphatic Duct?

lymph from right head, chest + arm

• drains into right subclavian vein re-entering circulation

What happens in the Thoracic Duct?

• collecting vessels from below the ribs converge to an enlarged lymph vessel

• drains into left subclavian vein re-entering blood circulation

What is the “enlarged lymph vessel” called?

cisterna chyli (most inferior portion of the thoracic duct)

STUDY PHOTO #1

ANSWER FOR PHOTO #1

• summary is that its a one way route back to blood

What are the different types of Lymphatic tissues and Organs?

• Primary Lymphatic Organs + tissues

• Secondary Lymphatic Organs + tissues

What are the Primary Lymphatic Organs + Tissues

• red bone marrow

• thymus gland

What happens in the Red Bone Marrow

• lymphocytes arise here

• B lymphocytes mature and proliferate (mitosis) here

What happens in the Thymus Gland?

• T lymphocytes mature and proliferate (mitosis) here

What happens in the Secondary Lymphatic Organs + Tissues

where lymphocytes proliferate

What are the Secondary Lymphatic Organs + Tissues

• contains:

  • lymph nodes

  • spleen

  • Mucosal Associated Lymphoid Tissue (MALT)

Where are the Lymph Nodes located?

cervical, axillary (armpit), inguinal (groin), intestinal, pelvic

What does the Spleen do?

filters blood

• e.g. removed bacteria

What are the Mucosal Associated Lymphoid Tissue (MALT)

e.g. tonsils, appendix, lymphoid tissues on mucous membranes

What are the Tonsils in the Mucosal Associated Lymphoid Tissue

• adenoids = pharyngeal (1) – nasopharynx

• palatine (2) – in oropharynx – commonly removed

• lingual (1) – base of posterior part of tongue