National Cancer Institute at the National Institutes of Health
Seer Training Modules: Introduction to the Lymphatic System
Self-guided learning activity where students learn about the structure and function of the human lymphatic system. There is a short quiz at the end of the lesson to check for understanding.
Biology Pages
Kimball's Biology Pages: T Helper Cells
A good site devoted to the T-cell and its role in the immune response. Complete coverage including vocabulary links throughout.
Biology Pages
Kimball's Biology Pages: B Cells and T Cells
A very strong overview of cell mediated immunity and the roles of the different cells within the system.
The College of Physicians
The History of Vaccines: How Vaccines Work [Pdf]
The purpose of this lesson is to relate the action of vaccines to the human immune system. In this lesson, students will explore infectious disease and immunity and learn how vaccines help the body defend itself against infectious diseases.
CK-12 Foundation
Ck 12: Life Science: B and T Cell Response
[Free Registration/Login may be required to access all resource tools.] Some defenses, like your skin and mucous membranes, are not designed to ward off a specific pathogen. They are just general defenders against disease. Your body also...
Khan Academy
Khan Academy: Activation of T Lymphocytes
Read a passage about the activation of T lymphocytes and answer the follow-up questions to practice for the MCAT.
Other
Hon: Helper T Cell
A very short, but decent, introduction to the function of the memory cells, this page has abundant links to vocabulary help.