Aquatic Life – Invertebrate Animals

1. Aquatic Life – Invertebrate Animals In this unit we will introduce characteristics of aquatic organisms and focus on invertebrate animals (that lack a backbone). Photo Credit: Photograph by Chris Newbert/Minden Pictures

2. Characteristics of Animals • All animals areeukaryotic; their cells have a nucleus and specialized organelles. • Their cells DO NOT have cell walls, differentiating them from bacterial and plant cells. • All animals are multicellular. • Because animals cannot make their own food they are considered heterotrophs .

3. Essential Functions • Homeostasis • Feeding/Excretion • Support/Movement • Respiration/ Circulation • Response to Environment • Reproduction http://photography.nationalgeographic.com/photography/photos/schools-fish/school-of-grunt-fish-photography.html

4. Feeding and Excretion • Animals must find, consume, and digest food for energy. • They must also get rid of waste products. • Just as the machines in a factory produce waste, the cells of organisms often produce a “trash” substance called ammonia which is poisonous. • The excretion (to get rid of) of wastes from the bodyvaries between organisms. http://photography.nationalgeographic.com/photography/photos/colorful-sea-creatures/pygmy-seahorse-doubilet.html

5. Support & Movement • Most animals are active and require energy for movement. • Some animals are sessile, or permanently attached to one spot (EX sponges). • Most animals are motile and are free-moving at some time in their life cycle (which allows offspring to settle in a new place). • Some animals are passive and move only when carried by another force such as water currents or wind. http://photography.nationalgeographic.com/photography/photos/underwater-scenes/basket-sea-star-photography.html

6. Respiration & Circulation http://www.tunalab.unh.edu/IMAGES/gills.jpg • Animals must have oxygen to release energy within cells. • Some animals use lungs while some aquatic animals use gills to bring in oxygen and get rid of the CO2 by product of cellular activity. • Others use diffusionto pass the gases in and out of their body.

7. Response http://photography.nationalgeographic.com/photography/photo-of-the-day/shark-kingman-reef-pod.html • Animals must be aware of their environment to obtain food, seek protection from predators, find mates and reproduce, etc. • Animals respond to their environment using specialized nerve cells to sense external stimuli(light, sound, etc) and to process information. • EX The shark using senses.

8. Reproduction • Animals must reproduce to maintain the species. • Most reproduce sexually using sperm and an egg. • Some can reproduce asexually (from just one parent). http://z.about.com/d/biology/1/0/-/2/pbear.jpg

9. Animal Body Symmetry • Radial symmetry – arrangement of body parts around a central point (EX starfish). • Bilateral symmetry – arrangement of body parts along a plane (EX heart, centipede). • Asymmetry – lack of symmetry (EX sponge). http://www.biologycorner.com/resources/symmetry_comparison.gif

10. Invertebrates vs. Vertebrates • The animal kingdom is divided into two main groups: • Invertebrates – without backbones • Vertebrates– with backbones http://www.bbc.co.uk/schools/revisewise/images/science/liv03b/03bfimg1.gif

11. Phylum Porifera • Sponges are the oldest and simplest and probably most unusual animals, classified in the Phylum Porifera. • Name means “pore-bearer” and are often seen in their dried form as natural sponges used for bathing. http://www.lpdatafiles.com/data/mso2003/SCUBA%20SPONGES.jpg

12. Sponge Characteristics • Sponges are sessile organisms that do not move (as adults). • No symmetry (asymmetry) • Sponges lack special tissues and organs. • They have special structures that allow water to pump through their body which help the sponge to respire and filter food and excrete waste. • Sponge Video http://www.scubaheartland.com/photos/sponges.jpg

13. Phylum Cnidaria • Think floating jellyfishand sea anemones (home to Nemo)! • Found in water all over the world, Phylum Cnidaria (C is silent) are soft bodied, carnivorous animals that have stinging tentacles. • Cnidarians link http://san-pedro-aquarium.california-california.info/Cnidarians.gif

14. Cnidarians Characteristics http://www.hawaiisfishes.com/inverts/cnidarians/Anomalorhiza_shawi.JPG http://www.mbgnet.net/salt/animals/1coral.jpg

15. Cnidarians Cont. • Cnidocytes– unique cells that contain stinging, poisonous barbs that are used to capture prey found on their tentacles. • The display radial symmetry. • Reproduce sexually or asexually (1 way) by budding • Cnidarians make upthe world’s coral reefs and float along with currents. • Stunning Jelly (Search jellyfish) http://www.corkvisioncentre.com/corkvisioncentre/Images/Underwater-Realm-2.jpg

16. Cnidarians Examples • Cnidarian Video http://www.ucihs.uci.edu/biochem/steele/Physalia.htm http://www.imagequest3d.com/photos/combjellies/index.htm

17. Phylum Platyhelminthes – Flatworms • Flatworms are classified as part of the Phylum Platyhelminthes. • Flatworms are un-segmented (no rings) and appear flat, most no more than a few millimeters thick. • They have tissues and internal organs systems, bilateral symmetry, and cephalization (which means they have a head!) • Flatworm video http://www.ucmp.berkeley.edu/platyhelminthes/pseudobiceros.jpg

18. Flatworm Characteristics • They have a single digestive opening, a Mouth/Anus in which food enters and undigested waste leaves. • Because they are so thin, most flatworms do not need a circulatory system to transport materials, but use diffusion. • Respiration also occurs through diffusion. http://www.emc.maricopa.edu/faculty/farabee/biobk/flatworm.gif

19. Flatworms Cont. • They move to obtain food and escape predators. • They can be both carnivorous or parasitic (this tapeworm lives inside the human intestines). http://biology.ucok.edu/AnimalBiology/Platyhelminthes/tapeworms.jpg

20. Phylum Nematoda/Nemertea – Roundworms • Also known as roundworms, Phylum Nematoda consists of unsegmented worms that can be microscopic or a large as a meter in length! • Most roundworms are free living and are found in the soil, the sea floor, or water. • Others are parasites that live in plants and animals. http://www.robots4farms.com/scubadivingpictures_files/daphneislet_files/99_jms_RoseRibbonWorm_90p_P2250080.jpg

21. Phylum Annelida – Segmented • Think earthworms and leeches! • Phylum Annelida consists of the common earthworm and is characterized by worms with segmented bodies. • The name means “little rings”. • Worm Video http://www.corbisimages.com/images/67/CC068D92-8C8A-4D6F-AC05-0092B9A74CF7/FL006311.jpg

22. Phylum Mollusca • Think snails, clams, and the octopus! • Mollusks are characterized by soft bodies that is sometimesprotected by a hard shell. http://www.greenfacts.org/images/glossary/mollusk.jpg

23. Mollusks Cont. http://www.uni-giessen.de/uni/broschuere/FB08-Nautilus.jpg

24. Classes of Mollusks • Kingdom Animalia / Phylum Mollusca / Class… • Class Polyplacophora (Chitons – most primitive mollusks) • Class Gastropoda (mollusks with shells; EX snails) • Class Bivalva (mollusks with a hinged shell; EX clams and oysters) • Class Cephalopoda (advanced, intelligent mollusks; EX nautilus, squid, octopus, cuttlefish which have a closed circulatory system) http://www.gochart.com/dig_photo/clams.JPG http://www.saczoo.com/3_kids/20_camouflage/images/octupus.jpg

25. Phylum Echinodermata • Think starfish (sea stars) , sand dollars, and sea urchins! • Phylum Echinodermata means "spiny skin“ and these organisms live only in the ocean. • Echinoderms have the ability to regenerate their limbs. http://www.museums.org.za/bio/images/mb/mb0556x.jpg

26. Echinoderms Cont. http://www.wetwebmedia.com/ca/cav1i4/echinoderms/sea_apple.jpg These are the elaborate filter-feeding tentacles of a Sea Apple.

27. Echinoderms Cont. • Kingdom Animalia / Phylum Echinodermata / Class… • Class Asteroidea – sea stars or starfish • Class Ophiuroidea – brittle stars and basket stars • Class Echinoidea – sea urchins and sand dollars • Class Holothuroidea – sea cucumbers • Class Crinoidea – sea lilies and feather stars http://www.cse.ucsc.edu/~ejw/tatum/images/urchins.jpg

28. Phylum Arthropoda • The butterfly, the spider, and the shrimp all belong into the Phylum Arthropoda, which means “jointed feet”. • Characterized by bilateral symmetry, they have segmented bodies fused into larger body regions. • Arthropod Video http://content.answers.com/main/content/wp/en/thumb/9/99/150px-Zorak-Mantis.png

29. Their jointed feet are specialized for sensing, eating, reproducing, moving and defending. Arthropods have a complex digestive system with two openings and a closed circulatory system (blood vessels like us). Exoskeleton - made of chitin; is a hard covering on the outsideof body which provides both support and protection Molting – required for an arthropod to grow; sheddingof old exoskeleton Arthropod Characteristics http://www.vifishandwildlife.com/Education/FactSheet/Images/Lobster.jpg

30. Arthropoda Subphylum: Crustaceans • Think crawfish, lobsters, and crabs! • Crustaceans have legs with claws, chewing mouthparts, two pair of antennae, and two body segments. http://www.mbari.org/seminars/2004/fall2004/shrimp.jpg