Lymphatic system

Lymphatic system

• secondary transport system

• Returns tissue fluid to the blood

Tissue fluid

• plasma with no red blood cells, platelets or large proteins

• Surrounds body cells & transports materials in and out of cells

Drained tissue fluid

Tissue fluid s formed constantly = must be removed and returned to blood (prevent swelling)

• 90% drawn back into plasma by osmosis

• 10% enters lymph vessels = now called lymph

Lymph vessels

Dead-ending vessels

Lymph

• Tissue fluid that entered lymph vessels.

• Contains white blood cells, proteins and fats

How does lymph move trough the body?

• muscular walls of the vessels

• General body movements pressing on lymph vessels

• Valves ensure lymph only moves towards shoulders

2 main lymph vessels

1. Thoracic duct - left side of the body

2. Right lymphatic duct - right shoulder

Empty lymph into subclavian veins

Lymph nodes

Swellings found along lymph vessels.

Fight infection by:

• filtering bacteria & other harmful material from lymph

• Mature and store lymphocytes

Where can lymph nodes be found?

• tonsils

• Adenoids (back of the nose)

• Neck

• Armpits

• Thymus gland

• Spleen

• Groin

Function of lymphatic system

• collect tissue fluid and return it to the blood

• Fight infection

• Absorb and transport fats