Lymphatic System

What is the body's third line of defense?

What is a sub type of white blood cells?

Amount of lymphocytes the human body has roughly

Where are the majority of lymphocytes found?

B cells mature in ____?

T cells mature in _____?

Which organ produces lymphocytes?

Which organ traps pathogens?

Which organ is located in the upper chest?

Which organ filters pathogens and worn out blood cells?