Unit 3 Option 2 – HS130-05
Discuss the morphology of the lymphatic system. Also, compare B and T lymphocytes and their roles in immunity. The lymphatic system is responsible for helping the human body fight against diseases and illnesses. This system consists of ducts, organs and nodes and transports fluid called lymph. The system contains cells called lymphocytes. Lymphocytes protect the body from antigens. The ducts of the lymphatic system are the home for B-cells and T-cells, these ducts also provide transportations for fats, proteins and other substances like lymph. Lymph is the fluid and protein that is squeezed out of the blood. The lymphatic vessels started out as a series of sacs developed by capillaries. Lymphatic capillaries are wide, colorless and have low pressure. The purpose of lymphatic vessels is to absorb and return lymph fluid from the body back to the blood. B cells (B lymphocytes) are an important component of the immune system. They are responsible for making antibodies against antigens. B cells are produced in the bone marrow they either stay there or move into the thymus gland, where they become T cells. T cells (T lymphocytes) acts as soldiers, they destroy “invaders” or foreign antigens. B cells acts as the body’s intelligence system. When foreign substances are detected cells work together and they respond by triggering b cells to produce antibodies. This is also an example of how shots prevent diseases. http://kidshealth.org/parent/general/body_basics/immune.html Chapter 13- The lymphtic system and immunity.