which one of the following discoveries involving dna happened first?           a. avery discovered that dna was responsible for storing and passing information through generations.   b. griffith learned that a chemical changed harmless cells into harmful cells.   c. hershey and chase used bacteriophages to confirm that dna was the genetic material in genes.   d. chargaff discovered that base pairing was consistent in samples of dna.

Which of the following statements is correct in hour our immune system responds to a potential pathogen? a. the adapted immune system will call on the innate immune system to destroy the pathogen. b. b cells will start reading the antigen code immediately and call t cells to assist in destroying the pathogen. c. the skin will be the first line of defense, and then the many phagocytes in the bloodstream will attempt to consume the possible pathogen. d. the t-cells in the adapted immune systems are the first to recognize the pathogen vaccines are weakened forms of disease causing microorganisms, which are given to patients to prevent disease. after the vaccine is administered, the immune system responds by creating a(n) to recognize the a. antigen, antibody b. antibody, antigen c. antibody, antibiotic d. antibiotic, antibody