Bellringer 3/2 Describe what do you think happened to your flatworm child? How did this happen? Have you ever consumed a parasite? Announcements: There will be a Quiz on worms next week!

In the lab: Make your day 2 observations of your flatworm child(ren) When finished return to the classroom and work on row three of your phylum table

“...if all the matter in the universe except the nematodes were swept away, our world would still be dimly recognizable, and if, as disembodied spirits, we could then investigate it, we should find its mountains, hills, vales, rivers, lakes and oceans represented by a film of nematodes.”  Nathan Cobb, 1915: Father of US Nematology 

Roundworms (Nematodes) They can be found everywhere, including in and atop soil and in the water. Parasites. Along with infecting dogs, roundworms can infect humans, cats, birds and many other types of animals.

Classes There are 2 classes of roundworms: Parasitic Non-parasitic

Characteristics of Roundworms All Nematodes: are invertebrates, and many are microscopic have an elongated, slender, snakelike shape move with a whip-like motion (no muscles, but a hydrostatic skeleton) have a sense of touch, can detect light & certain chemicals Breathe across their whole body

Nematode Video Movement: Explain why roundworms move so crazy.

Disease-causing Roundworms: Elephantiasis Worm infects blood and lymph vessels Transmitted by mosquitoes Tropical parts of Asia Swelling caused by blockage of lymph vessels

Disease-causing Roundworms: Ascaris Parasitic roundworm Affects humans, cats, dogs, horses, pigs, chickens Cause severe malnutrition Spread by eating food or water contaminated with Ascaris eggs Intestine filled with Ascaris

Ascarids taken from children of one village.

Disease- causing roundworms: Trichinella Transmitted by consuming improperly cooked pork Trichinosis Disease caused by trichnella

Trichinella completes its life cycle only when another animal eats muscle tissue containing these cysts. Humans can get trichinosis by eating raw or incompletely cooked pork.

Hook Worms Enter the body through the skin on the soles of the feet Live in the blood and intestines

Hookworms Necator Hookworms penetrate the bottoms of bare feet. Do not go barefoot. This patient presented with a hookworm infection involving the toes of the right foot, which is also known as “ground itch”. Usually the first sign of infection is itching, and a rash at the site where skin touched contaminated soil or sand, which occurs when the larvae penetrate the skin, followed by anemia, abdominal pain, diarrhea, loss of appetite, and weight loss..

Guinea Worms

Guinea Worms Dracunculus medinensis

Bell Ringer 10/20 How are roundworms different from cnidarians or flatworms Describe the body of a roundworm. Please have out your worm webquest, unsegmented worm note sheet and planarian lab.

Label the round worm on your note sheet

Roundworms Roundworms