Class Trematoda: Infect the internal organs of hosts. Parasitic Can be endoparasites (live in the host) or ectoparasites (attach to external surfaces of the host. Size: ~ 1 cm to 10 cm Covered in an unciliated cuticle. Usually require 2 hosts to complete it's life cycle.
Warts are generally caused by a human virus known as papilloma while moles are generally related with age and caused by hormones and environmental factors. There are cases when kids are born with moles but in general moles on the face increase with increase in age.
What are warts and verrucas? Warts are small rough lumps on the skin. They are caused by a virus (human papillomavirus) which causes a reaction in the skin. Warts can occur anywhere on the body but occur most commonly on hands and feet. They range in size from 1 mm to over 1 cm. Sometimes only one or two warts develop.