1 / 13

Ichthyes: The Fish

Ichthyes: The Fish. What is a Fish? Aquatic vertebrate, usually with paired fins, scales and gills. -fins for movement -scales for protection -gills for respiration -Very diverse group composed of many classes of fish. -. Evolution of Fish -Fish were the first vertebrates

hila
Download Presentation

Ichthyes: The Fish

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. Ichthyes: The Fish

  2. What is a Fish? • Aquatic vertebrate, usually with paired fins, scales and gills. • -fins for movement • -scales for protection • -gills for respiration • -Very diverse group composed of many classes of fish. • -

  3. Evolution of Fish -Fish were the first vertebrates -Two important developments : - jaws - paired fins The First Fish -Strange, jawless animals with bone armour. -Lived 500 million years ago and didn’t change for 100 million years

  4. The Age of Fish -400 million years ago -all were jawless -both soft-skinned and armoured fish appeared

  5. The Arrival Of Jaws and Paired Fins

  6. Jaws -allowed fish to eat new types of food -gave them protection Paired Fins -paired pectoral and pelvic fins -fins attached to girdles, b0ne structures in the body -fish could now swim quickly, hunt and protect themselves

  7. ModernFish Agnatha: jawless fish http://www.youtube.com/watch?v=Bb2EOP3ohnE Chondrichthyes: cartilage fish Osteichthyes: Bony fish

  8. Feeding • every mode of feeding • Some will eat anything, others are very specialized • Food: • Enters mouth • Into esophagus • Stomach • Broken down further in the Pyloric Seca • Intestine • Anus • Respiration • Most fish move water over their gills and take out the oxygen • Most fish have a single gill opening protected by the operculum • Lungfish have organs like lungs and can breathe air

  9. Circulation • Closed circulatory system (blood is in vessels) • A heart moves the blood in a loop around the body: heart-gills-body-heart • Complex, four-chambered heart • Excretion • -Waste is removed in the form of ammonia • Kidneys help fish control the water in their bodies • Response • -Well-developed brain with different parts • -Most fish have good sense organs • -Lateral Line System lets fish feel movement in the water

  10. Movement: -muscles bend their bodies in a S-shaped movements -fish move forward -fins stabilize and steer -body is streamlined -many fish have a swim bladder to help them float

  11. Reproduction -can be either internal or external fertilization -fish that hatch from eggs are oviparous

More Related