Echinoderms Echinoderms have a hard endoskeleton

covered by bumpy or spiny epidermis; They have radial symmetry, a mouth, stomach,

and intestines. They have no head or brain, but they do have a

nerve ring around the mouth. They have a water-vascular system connected

to thousands of tube feet. EX.~sea stars, brittle stars, sea urchins, sand

dollars, sea cucumbers

IN- What advantage does being able to reproduce sexually & asexually have for animals like sponges, cnidarians, mollusks & Echinoderms?

OUT- How do tapeworms get energy?

Monday November 4th

Flatworms

Invertebrates w/soft bodies and bilateral symmetry. They have three tissue layers organized into organs and organ systems.

Ex.~Planarians, Flukes, and Tapeworms Free-living vs. Parasitic- a parasite depends on

another organism for food or a place to live.

Planarians Free-living flatworm One body opening-a mouth Most hermaphrodites Ability of regenerate

IN- Explain the difference between free-living and a parasitic flatworm.

OUT- Why do parasitic worms often cause weight loss in their host organism?

Flukes Parasites w/complex life cycle (snails,

animals and humans are hosts) Infect more than 200 million people,

estimated 1 million people die each year, can infect the lungs, liver, eyes and other organs

Some do infect plants and some are free-living in the soil.

Tapeworms Parasites found in dogs, cats, humans and other

animals are hosts for tapeworms. Doesn’t have a mouth or digestive system,

absorb food that is digested by the host from its host’s intestine.

OUT- Explain what a “host” is in terms of a parasitic relationship and give an example.

S_____

IN-Fill in the levels of complexity diagram below.

IN- List and give an example of the 3 classes of flatworms1.2.3.

OUT- fill out the Venn diagram

FlatwormRoundworm

SegmentedBodiesBilateral3 tissue layers

Is it lunch time yet? Nope just time for a little

roundworm

Roundworms-

Ascariasis : Ascariasis is an infection caused by the roundworm Ascaris lumbricoides . Infection occurs when an individual consumes food or drink contaminated with fecal matter that contains mature worm eggs. Adult worms can reside in the small intestine and produce eggs for a year or more.

Roundw

orm

s-con’t

Hookworm (ancylostomiasis) : A hookworm infection occurs when larvae of the roundworms Ancylostoma duodenale or Necator americanus penetrate human skin, making their way through the lungs to the small intestine, where they attach and mature into adults, laying more eggs. Children are particularly susceptible to this kind of infection. Once infected, children become weak and experience stunted growth patterns. These roundworms infect about 25 % of the world's population

More bugaboos

Pinworm (enterobiasis) : A pinworm infection occurs when an individual consumes food or drink contaminated with fecal matter containing the roundworm Enterobius vermicularis . After being ingested, eggs hatch in the small intestine, and adult worms ultimately inhabit the large intestine. The pregnant female worms migrate to the anus and deposit large numbers of eggs in the skin around that area. Pinworm, which is commonly spread in day care centers, schools, and camps, affects as many as 1/3 of all American children

They keep coming Trichinosis (trichiniasis) : Trichinosis is

an infection caused by the roundworm Trichinella spiralis . These larvae live in pigs and other wild carnivores, such as bears, but humans can become infected with Trichinella spiralis when they eat such meat (particularly pork) that is undercooked. The larvae mature in small intestines and migrate to muscle cells where they can live for months or years.

River blindness (onchocerciasis)

River blindness (onchocerciasis) : River blindness is an infection caused by the roundworm Onchocerca volvulus . Onchocerciasis, which is spread by day-biting flies, is the leading cause of blindness worldwide, affecting about 20 million people, mostly in Africa

IN- List several examples of Roundworms

OUT- How can humans preVent infection from many roundworms?

1. ______2. ______3. ______

So what is the bottom line?

Probably the best solution to the problem of roundworms rests in preventing these infections rather than in curing them. The steps to preventing roundworm infection include:

Practice good personal hygiene (such as washing hands and avoiding contact with fecal matter).

Avoid uncooked or unwashed fruits and vegetables in areas where sanitation is poor.

Avoid mosquito or fly-infested areas, unfiltered water, and direct skin contact with soil in areas where roundworm infections are prevalent.

Preventive Care Wear protective clothing, and use insect

repellant. Cook or freeze meat thoroughly. Keep children away from pet feces. Consult a veterinarian about deworming

pets. Public health measures in areas where

roundworm infections are prevalent include improving general sanitation, especially sewage disposal, and reducing mosquito and fly populations.