Why do children in comparison with adults represent a group that is especially vulnerable to environmental hazards? choose the incorrect answer. a. they may be exposed more often to toxins in the outdoor air. b. they spend more time indoors. c. they may be exposed more often to toxins in the soil. d. they may inadvertently ingest toxic substances e. their immune systems are still developing?

Explain two reasons you think it is important for scientists to search for new ways to treat cancer

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 matches the organisms described with the correct domain? a. archaea--multicellular, eukaryotic organisms that do not have cell walls b. eukarya--single-celled and multicellular organisms, with a defined nucleus and a variety of nutritional sources c. bacteria--unicellular, eukaryotic organisms with cell walls that do not contain peptidoglycan d. bacteria--unicellular, eukaryotic organisms that always lack cell walls