1 / 24

Worms

Worms. Flatworms, Roundworms, and Segmented Worms. Science7. Characteristics of Worms. All worms share the following characteristics: Invertebrates Long narrow bodies without legs Tissues, organs, and organ systems (with brain) Bilateral Symmetry (head and tail ends)

lanza
Download Presentation

Worms

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Worms Flatworms, Roundworms, and Segmented Worms Science7

  2. Characteristics of Worms • All worms share the following characteristics: • Invertebrates • Long narrow bodies without legs • Tissues, organs, and organ systems (with brain) • Bilateral Symmetry (head and tail ends) • Reproduction: Sexual and Asexual • 3 Cell Layers • Ectoderm • Mesoderm • Endoderm

  3. 3 Major Phyla of Worms • There are 3 major phyla of worms: • Platyhelminthes = Flatworms • Nematoda = Roundworms • Annelida = Segmented Worms

  4. Flatworms • From 2 Greek words: • Platy means “flat” • Helminthe means “worm” • Simplest of all worms • Flattened bodies • Most are parasites and get food from host

  5. Flatworms: 3 Types • There are many kinds of flatworms: • Planarians • Tapeworms • Flukes

  6. Flatworms: Tapeworms • Tapeworms • Lives in the intestines of animals (including humans!) • Uses hooks and suckers on its head to dig into the lining of an organism’s digestive tract • Considered Parasitic • Blocks the host’s intestines • Steals valuable food and water • Can grow 10-12 meters in length

  7. Life Cycle of A Tapeworm

  8. Flatworms: Planarians • Planarians • Scavengers • A feeding tube releases digestive juices to break down food. • THINK! – What type of digestion is this? • Odor cells are found on the head • THINK! – What do the odor cells help with? • Planarians have 2 photosynthetic eyespots • THINK! – What do the eyespots detect? • Watch Planarians :55

  9. Flatworms: Flukes • Flukes • Usually live in the human liver • Shape: Oval and flat • Size: 2mm -15 cm

  10. Activity: Draw A Flatworm • Draw, color, and label the diagram of this flatworm in your guided notes. Digestive Tract (red)

  11. Roundworms • General Characteristics: • Cylindrical bodies • Contains a digestive system • Food enters at a mouth • Waste exits through the anus

  12. Roundworms: Trichinella • Trichinella • Lives in muscular tissue of pigs • These worms reproduce in the intestine of the host • Female worms release hundreds of immature worms carried in the bloodstream • These immature worms burrow in the surrounding tissue causing pain to the host

  13. Roundworms: Hookworms • Hookworms • Enter the body by burrowing through the soles of feet • Eventually ends up in the intestines where they live off of blood

  14. Roundworms: Pinworms • Pinworms • Small white parasitic worms found in the feces of babies • Babies sometimes ingest microscopic eggs from the soil

  15. Activity: Draw A Roundworm • Draw, label, and color this diagram of a roundworm in your guided notes. Compare it to a cnidarian which we just learned about.

  16. New Guinea Worm: Life Cycle http://www.dhpe.org/infect/guinea.html

  17. New Guinea Worm Emerging

  18. Video Clip • Worms have many unique characteristics different from sponges and cnidarians. • Watch this clip: “Three Phyla of Worms_5min 45 sec” • Listen for the characteristics that worms were the first to have!

  19. Segmented Worms • Characteristics • Annelida is Latin for “Little Rings” • Body is made of many segments • An earthworm has more than 100 segments! • Organs are found within the segments

  20. Segmented Worms: Closed Circulatory System • Closed Circulatory System • Blood moves within a confined set of blood vessels • Five hearts are located in segments 5-13

  21. Segemented Worms: Earthworms • How they live • They tunnel for a living • They are scavengers eating dead plant and animal remains • They crawl by using stiff bristles (setae) to pull themselves along

  22. Segmented Worms: Earthworms • Earthworms and Soil • Earthworms make soil more fertile • Their tunnels help loosen the soil and allow air, water, and plant roots to move through it.

  23. Activity: Draw a Segmented Worm • Draw, color, and label this diagram of a segmented worm in your guided notes. Gizzard Crop (setae) Pharynx Esophagus Digestive Tract (System) starts in Mouth Pharynx - throat Esophagus – connects throat to crop Crop – storage Gizzard – grinds Intestine – absorbs nutrients Anus Color Key for Organ SystemsDigestive System Circulatory System Nervous System Reproductive System Excretory System

  24. Leeches are Segmented Worms • NOVA Clip_ Leeches_11min! • Leeches can be very helpful worms! • Fill out your Ticket Slip as you are viewing.

More Related