one white roundworm parasite

abdominal anatomy animal ascariasis ascaris babyworm background biology blood bowel cat childworm diarrhea digestive disease dog education endoparasite fecal female health healthcare helminth human hygiene infectious intestinal invertebrate isolated lumbricoides malnutrition medical microbiology microscope nature nematode one parasitic roundworm sanitation scary science slide small tapeworm ugly white wildlife worm zoology