Host–Pathogen Interactions Study Guide

A comprehensive set of 50 vocabulary flashcards covering key concepts related to host-pathogen interactions, immune responses, and infectious diseases.

Good Bacteria

Microorganisms that help keep our body balanced, making vitamins and fighting off harmful microbes.

Bad Bacteria

Microorganisms that cause infections or release toxins.

Normal Microbiota

Microbes that live on us daily, contributing to health.

Resident Microbiota

Microbes that are always part of our body.

Transient Microbiota

Microbes that appear for a short time but do not stay

Opportunistic Infections

Infections arising when non-pathogenic bacteria take advantage of a weakened immune system.

Pathogenicity

The ability of a microbe to cause disease.

Virulence

the degree of a toxin, virus, or microorganism that cause disease

Virulence Factors

Characteristics that enable pathogens to adhere, evade immune cells, damage host tissues, and spread.

Stages of Infectious Disease

Incubation, Prodromal, Illness, Decline, Convalescence

Entry

The first step pathogens take to cause disease, involving entering the body.

Adhesion

The process of pathogens sticking to host cells using proteins.

Invasion

The act of pathogens entering deeper into body tissues.

Evasion

When pathogens avoid detection and destruction by the immune system.

Damage

Destruction of cells or release of toxins by pathogens.

Reservoirs of Infection

Places where pathogens normally live, such as humans, animals, or soil.

Portals of Entry

Routes through which pathogens enter the body, including skin and mucous membranes.

Mucous Membranes

Barriers that trap pathogens in eyes, mouth, nose, or GI tract.

Parenteral Route

Entry through needles, cuts, bites, or any breaks in the skin.

Fimbriae

Hair-like structures that help pathogens adhere to host cells.

Phagocytosis

The process by which immune cells engulf and digest pathogens.

Cytokines

proteins that act as messengers for the immune system, helping cells communicate with each other to regulate immune responses to inflammation, infection, and other diseases

pathogen-associated molecular patterns (PAMPs)

Patterns found only on pathogens that signal the immune system about foreign invaders.

Complement System

a group of proteins in the innate immune system that helps the body fight pathogens like bacteria and viruses

Opsonization

Tagging pathogens to enhance phagocytosis.

Fever

A response that slows down pathogens and enhances immune function.

Humoral Immunity

Immune response involving B cells and the production of antibodies.

Cell-Mediated Immunity

the immune response where special cells, like T-cells, directly attack

T Cells

a type of white blood cell that are a crucial part of the body's immune system

B Cells

White blood cells responsible for humoral immunity and antibody production.

Memory B Cells

a type of B cell that provides long-term immunity by "remembering" a specific pathogen

Active Immunity

When the immune system produces antibodies in response to an antigen

Passive Immunity

When a person receives antibodies from another source.

Vaccines

Preparations that stimulate an immune response without causing disease.

Herd Immunity

When enough people are immune to a disease, preventing its spread.

Attenuated Vaccines

Vaccines containing weakened live pathogens.

Inactivated Vaccines

Vaccines made from killed pathogenic agents.

mRNA Vaccines

Vaccines that instruct cells to produce harmless parts of a pathogen for immune recognition.

Neutrophils

A type of white blood cell important in the innate immune response.

Macrophages

Phagocytic cells that eat pathogens and present antigens to T cells

Dendritic Cells

Antigen-presenting cells that express both MHCI and MHCII.

Cytotoxic T Cells (TC)

T cells that kill infected host cells.

Helper T Cells

T cells that activate other immune cells, including B cells.

Antigens

Substances that trigger an adaptive immune response.

Complement Activation

A function of antibodies to enhance the immune response against pathogens.

ADDC

An immune response where antibodies flag a target cell for destruction by other immune cells, like natural killer (NK) cells

Interleukins

Types of cytokines that are crucial in the communication of immune cells.