Finals Flashcards: PLATYHELMINTHES (FLATWORMS) and NEMATODA (ROUNDWORMS)

Bilateral Symmetry

A body plan in which the left and right sides are mirror images.

Planaria

A free

Pharynx

A muscular feeding tube used to take in food.

Flame Cell

A specialized cell that removes excess water and waste.

Eyespot

A light

Regeneration

The ability to regrow lost body parts.

Parasite

An organism that lives on or in another organism and harms it.

Host

The organism a parasite lives on or in.

GVC (Gastrovascular Cavity)

A digestive cavity with one opening for food and waste.

Fluke

A parasitic flatworm.

Tapeworm

A parasitic flatworm that lives in the intestines of a host.

Scolex

The head of a tapeworm with hooks or suckers for attachment.

Proglottid

A body segment of a tapeworm that contains reproductive organs.

Flatworms (Platyhelminthes)

Soft

Function of the Pharynx in Planaria

Takes in food and delivers it to the gastrovascular cavity.

Function of Flame Cells

Remove excess water and maintain water balance.

Why Planaria Are Studied

They can regenerate lost body parts.

Anterior

The front end of an organism.

Posterior

The rear end of an organism.

Dorsal

The upper side or back.

Ventral

The lower side or belly.

Anus

The opening where waste leaves the digestive tract.

One

Way Digestion

Cuticle

A tough outer covering that protects roundworms.

Vinegar Eel

A free

Roundworms (Nematoda)

Worms with a complete digestive tract and a protective cuticle.

Difference Between Flatworms and Roundworms

Flatworms have one digestive opening; roundworms have a mouth and anus.

Ascaris

A parasitic roundworm spread by ingesting eggs in contaminated food or water.

Hookworm

A parasitic roundworm that enters through the skin, often from contaminated soil.

Trichinella (Trichina)

A parasitic roundworm found in undercooked pork and wild game.

Trichinosis

The disease caused by Trichinella infection.

Pinworm

A common parasitic roundworm spread through contaminated hands, food, or surfaces.

Filaria

A parasitic roundworm spread by mosquito bites.

Elephantiasis

A disease caused by filarial worms that results in severe swelling.

Guinea Worm

A parasitic worm contracted by drinking contaminated water.

How Ascaris Is Transmitted

Swallowing eggs in contaminated food or water.

How Hookworm Is Transmitted

Larvae enter through bare skin.

How Trichinella Is Transmitted

Eating undercooked infected meat.

How Pinworm Is Transmitted

Contact with contaminated objects or eggs.

How Filaria Is Transmitted

Mosquito bites.

How Guinea Worm Is Transmitted

Drinking contaminated water.

Importance of the Cuticle

Protects roundworms from digestion and harsh environments.

Advantage of One

Way Digestion

Mouth

Opening where food enters the digestive system.

Intestine

Organ where digestion and nutrient absorption occur.

Planarian Digestive System

Uses a gastrovascular cavity with one opening.

Roundworm Digestive System

Uses a complete digestive tract with a mouth and anus.

Example of a Free

Living Flatworm

Example of a Free

Living Roundworm

Examples of Parasitic Flatworms

Flukes and tapeworms.

Examples of Parasitic Roundworms

Ascaris, hookworm, pinworm, and filaria.