Mira analyzed oxygen and carbon dioxide in inhaled and exhaled air. She found that the percentages of both gases were different in each. What other gas would most likely also have different amounts in inhaled and exhaled air? ozone (O3) hydrogen (H2) water vapor (H2O) sulfur dioxide (SO2).

Which is an advantage of having memory cells when a pathogen is encountered for a second time. a) the memory cells are what proliferate into clones of cells in response to the binding of an antigen. b) memory cells are vital to the primary immune response in that they immediately recognize pathogens even at the first encounter. c) memory cells are essentially effector cells that are short lived and attack antigens even without having a receptor specific to that antigen. d) it ensures that more lymphocytes with a receptor specific to a particular antigen will be present than in a host that had never encountered that pathogen.

Which of the following is not a benefit of genetically modified foods? a. pest-resistant crops b. herbicide-resistant crops c. plants that do not require water?

Viruses can be transmitted through air, water, food, insect bites, and direct skin contact. once a virus gains entry into the body, it invades a host cell in order to? a. synthesize antibodies for defense b. deactivate the host cell's defenses c. access cell processes for reproduction d. metabolize host proteins and grow