S2 E1: Bump

S2 E2: Acquired Immunity/Peyer's Patch

S2 E3: Dengue Fever/Acne

S2 E4: H. Pylori/Antigenic Shift

S2 E5: Cytokines

S2 E6: Harmful Bacteria

S2 E7: Cancer Cell II (Part I)

S2 E8: Cancer Cell II (Part II)