Infectious Diseases, Immunity, and Antibiotics

Vocabulary flashcards covering key terms from the lecture notes on infectious diseases, immunity, and antibiotics.

Infectious disease

A disease caused by pathogens that can spread from one person to another.

Noninfectious disease

A disease not caused by pathogens and not transmissible between people; often linked to lifestyle or environment.

Transmission

The spread of an infectious disease from an infected person to others through droplets, direct contact, or contaminated food and water.

Droplets

Tiny respiratory droplets expelled when coughing or sneezing; may contain pathogens.

Mask

A protective layer that reduces release and inhalation of pathogen-containing droplets.

Social distancing

Maintaining physical distance to reduce exposure to respiratory droplets.

Direct contact

Spread through physical contact or exchange of bodily fluids.

Contaminated food and water

Food or water contaminated with pathogens, enabling transmission.

Bacteria

Single-celled organisms with a cell wall and cell membrane; lack a membrane-bound nucleus; may have ribosomes and plasmids; some are pathogenic.

Plasmids

Small circular DNA molecules in bacteria that can carry genes, including antibiotic resistance.

Bacterial DNA

Genetic material in bacteria, typically a circular chromosome located in the cytoplasm (no nucleus).

Virus

A non-cellular infectious agent with a protein coat enclosing genetic material (DNA or RNA) that replicates only inside living host cells.

Influenza

A respiratory illness caused by the influenza virus; signs include fever, cough, runny nose, muscle aches, headache, sore throat, and chills.

Pneumococcal disease

An infection by pneumococcus bacteria affecting various body parts; signs include fever, cough, shortness of breath, headache, vomiting, and photophobia; transmitted mainly via respiratory droplets.

Vaccination

A process in which a vaccine introduces an agent resembling a pathogen to stimulate the immune system to produce antibodies and memory cells.

White blood cells

Immune cells that detect pathogens and produce antibodies; different types have receptors for various antigens.

Antibodies

Proteins produced by B cells that bind to specific antigens on pathogens and help destroy them.

Antigen

A molecule or part of a pathogen that triggers an immune response.

Immunity

The body's ability to resist infection; can be long-lasting due to immune memory.

Memory cells

Long-lived immune cells that remember a pathogen and enable a quicker response on re-exposure.

Vaccine memory

Memory B and T cells formed after vaccination that provide faster protection upon later exposure to the pathogen.

Virus mutation

Viruses can mutate to form new strains; vaccines may need updating to cover new strains.

Antibiotics

Drugs that treat bacterial infections by killing bacteria or inhibiting their growth; generally ineffective against viruses.

Cell wall synthesis inhibition

Antibiotics that prevent formation of the bacterial cell wall, weakening and killing bacteria (e.g., penicillin).

Cell membrane function inhibition

Some antibiotics disrupt the bacterial cell membrane, compromising integrity.

Protein synthesis inhibition

Antibiotics that bind to bacterial ribosomes to prevent protein production.

Folic acid synthesis inhibition

Antibiotics that block enzymes needed to synthesize folic acid, hindering bacterial growth.

Antibiotic resistance

When bacteria become less sensitive to an antibiotic, survive treatment, and may spread resistance genes.

Reducing antibiotic resistance

Avoid overuse/misuse of antibiotics; complete prescribed courses; use antibiotics only when necessary.