B4 Lymphatic system Flashcards
Give the function of the spleen
Emergency supply of blood and white blood cells (leucocytes)
Describe how tissue fluid is formed
Forms at arterial end of blood capillary
High hydrostatic pressure created by heart
Small soluble molecules are forced out of blood in the capillary
Why does blood pressure fall along the capillary?
Friction/resistance of walls
Reduced blood volume
Name two components of blood that do not leave the capillary
Proteins
Cells
Why do proteins and blood cells remain in the blood and do not enter the tissue fluid?
Too large to pass out of capillary
Describe how tissue fluid moves back into the blood at the venous end of the capillary
Water potential of tissue fluid higher than the blood
OR
Osmotic pressure of blood higher than hydrostatic pressure
Water moves by osmosis back into the blood
What is the function of the lymph vessel in the diagram?
Drains excess fluid from the tissues
Returns to the blood near the heart
What is the purpose of tissue fluid?
Fluid used to deliver glucose and oxygen to every cell
Removes carbon dioxide and urea from cells.
Describe the structure of the lymphatic system
Extensive network of vessels
Large lymph vessels have sac like structures called lymph nodes