Disease

Pathogenic bacteria are bacteria that cause bacterial infection. Helpful Bacteria a.k.a. Probiotics are live microorganisms thought to be healthy for the host organism.

The immune system is a system of biological structures and processes within an organism that protects against disease. To function properly, an immune system must detect a wide variety of agents, from viruses to parasitic worms, and distinguish them from the organism's own healthy tissue.

In this video lesson we will be exploring both infectious and non-infectious diseases.