Untitled

Blood-brain barrier

Specialized epithelial cells that selectively allow only beneficial molecules through to prevent pathogens from entering the brain.

Innate response

The first and second lines of defense in the immune system that do not have memory of the pathogen and respond similarly on reinfection.

Saponin

A chemical barrier found in plants that reduces the pathogen's ability to grow.

Defensins

Plant chemical barriers that disrupt the cell walls of fungi or bacteria, preventing them from functioning normally.

Normal flora

Non-pathogenic bacteria living in the body that compete with pathogens for resources and space, forming a microbiological barrier against pathogens.

First line of defence

The barrier defense mechanism in the innate response that aims to keep all pathogens out through physical, chemical, and microbiota barriers.

Pathogenic bacteria

Bacteria that cause diseases or infections in animals and plants, such as Agrobacterium tumefaciens causing crown gall disease in plants.