Introduction to Infection, Immunity and therapeutics Flashcards
What are the three domains of life?
Bacteria – Peptidoglycan in cell wall (e.g., mitochondria, chloroplasts).
Archaea – No peptidoglycan (e.g., hyperthermophiles, extreme halophiles).
Eukarya – Animals, fungi, plants.
Why are microbes important?
Everywhere – Found all around us.
Food production – Used in beer, bread, and digestion.
Infections – Pathogenic bacteria, fungi, polymicrobial infections.
Environmental role – Break down organic material.
How are organisms named in microbiology?
By genus and species (e.g., Bacillus anthracis or B. anthracis).
What is the hierarchy of classification?
Life → Domain → Kingdom → Phylum → Class → Order → Family → Genus → Species.
Define an infection
When a foreign organism enters the body, reproduces, colonizes, and causes harm.
What is the formal definition of infection?
The state produced by the establishment of one or more pathogenic agents (bacteria, fungi, viruses, etc.) in or on a suitable host.
What are the main types of microorganisms?
Parasites – Helminths (e.g., tapeworms).
Protozoa – Plasmodia (e.g., malaria).
Fungi – Tinea (e.g., athlete’s foot).
Prokaryotes – Bacteria (e.g., leprosy).
Viruses – (e.g., HIV → AIDS).
Prions – (e.g., CJD).
What are living pathogens?
Parasites – Feed on a host (e.g., protozoa).
Fungi – Cause superficial/systemic infections.
Bacteria – Unicellular, rapidly reproduce.
What are non-living pathogens?
Viruses – Inert, require a host to reproduce.
Prions – Misfolded proteins causing disease
What is immunity?
The body’s ability to protect itself using the immune system.
What are natural barriers to infection?
Tears (enzymes), mucus (traps microbes), stomach acid (kills pathogens).
What are the two main immune responses?
Innate immunity – Non-specific, first line of defense.
Adaptive immunity – Specific, memory-based response.
How do innate and adaptive immunity differ?
Innate – Non-specific, no memory, phagocytes engulf pathogens.
Adaptive – Specific, memory-based, lymphocytes produce antibodies.
What is an antigen?
A molecule that triggers an immune response.
What are the types of acquired immunity?
Natural Passive – Maternal (e.g., breast milk).
Natural Active – Infection.
Artificial Passive – Antibody transfer.
Artificial Active – Immunization.
What are the main types of therapeutics?
Vaccination – Active or passive.
Bacteriophages – Viruses that target bacteria.
Antimicrobials – Antibiotics, antivirals, antifungals, antiparasitics.
Monoclonal Antibodies – Lab-made antibodies for specific infections.
What is the difference between a disease and an infectious disease?
Disease – General illness or disorder (e.g., non-communicable).
Infectious disease – Caused by pathogens, can spread (communicable).
What is an outbreak?
When a disease occurs in greater numbers than expected.
Define endemic, epidemic, and pandemic.
Endemic – Disease permanently in a region (e.g., malaria).
Epidemic – Widespread outbreak in a population.
Pandemic – Epidemic that spreads globally.
