Definitions to know: • Immunology: Study of the body’s specific defenses against pathogens. • Halophiles: salt lovers environment • Spirochete: Group of helical, Gram-negative bacteria with axial filaments that cause the organism to corkscrew, enabling it to burrow into a host’s tissues. • Mutualism: Symbiotic relationship in which both members benefit from their interaction. • Signs: Objective manifestations of disease observed or measured by others • Symptoms: Subjecti...