Pathogens-

Pseudomonas

Aeruginosa

http://www.flickr.com/photos/microbeworld/5716327361/

Polio

http://www.flickr.com/photos/wwworks/3562024338

Protozoans

http://www.flickr.com/photos/ericfortin/2182088930

Influenza Virus

http://www.flickr.com/photos/36128932@N03/3338845735/

http://www.flickr.com/photos/berkeleylab/2825656417/

Fungi

http://toenailfungustreatments.com/

Immune System

http://healthcenterinternationalresearches.webs.com/apps/blog/show/3915135-how-your-immune-system-works

Vaccine

Flagella- http://www.flickr.com/photos/striatic/3834479/lightbox/

Fruit Rind with harmful pathogens

http://www.flickr.com/photos/news21/6110298959/