c3.2

These flashcards cover key concepts related to pathogens, the immune system, vaccine functions, antibiotic resistance, and zoonotic diseases based on the provided lecture notes.

What are pathogens?

Organisms that cause disease and serve as starting points in the chain of infection.

How many species of pathogens are known to cause infections in humans?

Around 1400 species.

What type of organisms are bacteria?

Unicellular, prokaryotic organisms.

Name four diseases caused by bacteria.

Tuberculosis, Plague, Diphtheria, Cholera.

What are characteristics of fungi?

Unicellular or multicellular eukaryotic organisms.

List three diseases caused by fungi.

Ringworm, Thrush, Athlete’s Foot.

What unique feature do viruses have?

Require a living host cell for replication.

What are prions?

Infectious proteinaceous substances that cause degeneration of the nervous system.

Define commensal bacteria.

Naturally present bacteria that outcompete pathogens for nutrients and space.

What is the purpose of the innate immune system?

To provide a rapid and non-specific response against pathogens.

What is the function of phagocytes?

They ingest and digest foreign material, including pathogens.

What are antigen-presenting cells?

Cells that present antigens to activate Helper T-cells.

How do B-cells and T-cells interact during an immune response?

Helper T-cells activate B-cells to produce antibodies.

What does herd immunity mean?

Indirect protection from an infectious disease when a significant portion of a population becomes immune.

What types of vaccines exist?

Live attenuated, inactivated, RNA, DNA, and protein subunit vaccines.

Name two examples of zoonotic diseases.

Rabies and COVID-19.

What does antibacterial resistance result from?

The evolution of bacteria that enables them to survive despite the presence of antibiotics.

How does HIV affect the immune system?

It primarily targets and destroys helper T-cells, impairing immune response.

What is the purpose of vaccines?

To prompt the immune system to respond as if exposed to the real pathogen, creating memory B-cells.

List a common method for preventing zoonotic disease transmission.

Limiting human-wildlife interactions.

What defines a universal donor in blood types?

Blood Group O, which has no A or B antigens on RBC surfaces.

What is the role of helper T-cells in immunity?

To activate other immune cells, including B-cells and cytotoxic T-cells.

What are the four main blood groups according to the ABO system?

A, B, AB, and O.

What is the significance of the T-cell count in HIV infection?

It monitors the progression of HIV and the immune system's ability to fight infections.

What happens during the secondary immune response?

It is faster and stronger due to memory B-cells recalling previous encounters with antigens.

Why must vaccines sometimes be given in multiple doses?

To ensure long-lasting immunity and robust immune responses.