Transcript Roundworms- Powerpoint

•Roundworms are Parasites or Larva Migrans they are common in a
number of different animal species including dogs and cats.
•Roundworm specific to humans but this parasite is rarely found in
developed countries.
•Humans can become infected with animal roundworms by
accidentally ingesting eggs or larvae.
•Most of them are so small that they are not even noticed. These
parasites are actually fairly large, but unseen. These worms are
slender, round, and have no segments.
•Roundworms do not live in the desert.
•Roundworms live all over the world.
•Roundworms live in salt water, fresh water and the soil.
•There are lots of tiny roundworms living in soil, mud in lakes, ponds,
and streams.
•The worm will take in it's food by the mouth, digest it, and absorb it
as it moves in the intestine in the hollow space then wastes leave
through the anus.
•Roundworms are large groups of 12,000 species and are small
cylindrical worms.
•They have a body wall made up of a covering layer and two layers of
muscles and inside they are hollow.
•The intestine passes through this hollow space, as it is a tube with
openings at each end, one for the mouth and one for the anus.
•Roundworms reproduce sexually. Most species of roundworms have
separate males and females.
• Fertilization takes place inside the body of the female. Roundworms
that are parasites on animals often have complex life cycles.
•Two or three hosts may be involved in the life cycle of some
roundworms. In other roundworms such as the stages of the life cycle
take place in different organs of one host.
• Roundworms can reproduce up to 25 to 30 eggs.
•The intestinal roundworm
infection in humans follows the
ingestion of eggs that have
contaminated foods or soil.
• In the small intestine the larvae
through the intestinal wall,
reaching the lungs, where they
may produce a host sensitization
that results in lung inflammation
and fluid retention.
•About 10 days later, the larvae pass from the
respiratory passages into the digestive tract and
mature into egg-producing worms, which grow
to some 15 to 40 cm (6 to 16 inches) in length, in
the small intestine.