Infectious Diseases and Immune Responses Quiz

The Body's Response to Infection

• Viruses cannot reproduce by themselves and rely on the host cell's transcription and translation systems
• Pathogenic viruses like Hepatitis A, B, C, D, E, and Influenza viruses cause various diseases
• Ebola virus, a member of the Ebolavirus genus, attacks liver cells, endothelial cells, and immune cells
• Eukaryotic pathogens like malaria-causing protists and parasitic worms can infect humans
• Infectious agents can be transmitted through direct contact, indirect contact, vector-borne, inhalation, and ingestion
• The body's response to infection involves innate and acquired immunity, with three lines of defense
• The first line of defense includes skin and mucous membranes, which act as physical barriers and secrete chemicals
• The second line of defense involves macrophages, inflammation, and fever as protective responses
• The third line of defense includes lymphocytes, which recognize specific antigens and mature in different organs
• B lymphocytes produce antibodies to rid the body of antigens, while T lymphocytes attack host cells bearing the antigen
• Passive immunity involves the transfer of readymade antibodies, while active immunity is self-developed through exposure to antigens
• Allergies are acquired hypersensitivity disorders, while AIDS is caused by HIV, which weakens the immune system and leads to opportunistic infections