Chapter 27.4 Flashcards
Describe the body cavity of roundworms
They are psudocoelomates, they have muscles of their outer cavity but not their gut
How many tissue layers do nematodes have?
3
What evolved in the feeding system of nematodes regarding openings?
They have two, one for food and one for waste
What evolved in nematodes regarding sexes?
They have two different sexes and usually reproduce sexually
What kind of symmetry do nematodes have?
Bilateral
What does the unique body cavity of nematodes allow them to do?
More muscle movement
How do nematodes get their energy?
Other living things, they are active hunters
What are the four main types of parasitic nematodes?
Pinworms, hookworms, filarial worms, ascarids
Describe the symptoms and prevalence among school-age children of pinworms
Usually no symptoms except itching around the anus where the eggs are, almost 50% of schoolchildren have them
Describe the symptoms and life cycle of hookworms
Symptoms-mild diarrhea and cramps
Life cycle- enter through feet, travel through the blood to the lungs, where they are coughed up and swallowed, then live in the intestines
Describe filarial worms (body type, location in the body)
Long, thin worms that live as adults in the blood or other tissues of vertebrates
What is elephantiasis?
A condition caused by filarial worms that caused swelling
What is dog heartworm caused by?
A mosquito bite from a mosquito infected by filarial worms
Where do ascarids live?
Intestines of pigs, horses, and humans
What is the most common worm infection?
Ascarids
