1. Chapter 11 Invertebrates Life Science

2. Body Plans Bilateral Symmetry—can be divided into two mirror image halves Radial Symmetry—has parts arranged around a central point Asymmetry—no symmetry

3. Body Plans Bilateral Symmetry—can be divided into two mirror image halves

4. Body Plans Radial Symmetry—has parts arranged around a central point

5. Body Plans Asymmetry—no symmetry

6. All animals can be classified as belonging to one of two groups: Those with Backbones Those without Backbones OR

7. Animals without Backbones are called Invertebrates.

8. Phylum Porifera (Sponges) Porifera are Sponges found mostly in the ocean Porifera means “pore bearing” because sponges are covered in small pores They are the simplest of all animals They are asymmetrical & have no nervous system

9. Porifera Sponges: Filter Feeders Water is swept into pores Collar cells filter food particles from the water –Each collar cell digests its own particles of food The rest of the water flows into a central cavity and into a hole at the top called the osculum http://www.youtube.com/watch?v=T7E1rq7zHLc

10. Phylum Porifera (Sponges) If a sponge’s body is broken apart, separate cells will come back together and reform the same sponge. New sponges can also form from pieces broken off another sponge. Sponges can replace body parts, or regenerate

11. Phylum Cnidaria Cnidarians include jellyfish, hydra & sea anemones, and corals The word Cnidaria means “stinging nettles” because they use nematocysts to sting & capture prey They have radial symmetry and use a gut for digestion

12. Phylum Cnidaria cont’ All have tentacles and stinging cells that fire tiny barbed spears called nematocysts Feed by stinging their food and bringing it to the mouth with tentacles http://www.youtube.com/watch?v=-Tp38DUjUnM

13. Cnidarian Body Forms: Polyp- Shaped like vases and usually live attached to a surface Ex. Hydra- freshwater polyp Ex: coral Ex: sea anemone

14. Cnidarian Body Forms: Medusa- Looks like a mushroom with tentacles streaming down Ex. jellyfish

15. Phylum Cnidaria cont’ They have a simple nervous system, called a “nerve net” & a gut used for digestion –Nerve net- simple network of nerve cells that controls the movements of the body and tentacles –http://www.youtube.com/watch?v=Kuk v0AtIVdUhttp://www.youtube.com/watch?v=Kuk v0AtIVdU

16. Worms Platyhelminthes(flatworms) Nematodes(roundworms) Annelids (segmented worms)

17. Phylum Platyhelminthes Platyhelminthes means “flatworms”, meaning they have flat bodies Bilateral symmetry Clearly defined head Nervous system- nerves connecting 2 parallel nerve cords. Ganglia make up a primitive brain. Ex. Planaria Eyespots 2 Sensory lobes- on side of head, detect food Mouth is on under side – has only 1 opening

18. Phylum Platyhelminthes Examples: Flukes & Tapeworms Parasites –find their way inside the bodies of other animals, where they live and reproduce Tiny heads without eyespots or sensory lobes Special suckers and hooks for attaching to the host Tapeworms have no gut –They absorb nutrients from the intestine of host

19. Phylum Annelida Annelids are “segmented worms” that include leeches, earthworms & bristleworms Each segment on their bodies are identical except the head

20. Phylum Annelida cont’ Annelids have a closed circulatory system- heart circulates blood through blood vessels that form a loop They have a brain in the head & a nerve cord that connect the ganglia Most Annelids will scavenge anything edible or may be predators or even parasites

21. Annelids Example- Earthworms 100 to 175 segments Improve soil by burrowing tunnels, which allow air and water to reach deep into soil Stiff bristles (setae) help them move

22. Annelid: Earthworm Eat soil Food is taken in through the mouth, swallowed in the pharynx, travels through the esophagus, stored temporarily in the crop, ground up in the gizzard, nutrients are absorbed in the intestine, and wasted is excreted through the anus

23. Phylum Anellida cont’ Earthworm internal organs

24. Annelids Example- Bristle Worms Many varieties and brilliant colors All live in water –Some burrow through soggy sand and mud –Others crawl along bottom, eating mollusks & other small animals Feeds by filter feeding

25. Annelids Example- Leeches Most are parasites that suck other animals’ blood Aren’t all bad –used in medical treatments used to drain “bad” blood from sick people now used after surgery to prevent swelling near wound Make a chemical that keeps blood from forming clots

26. Phylum Mollusca All Mollusks share a similar body plan –They all have a: soft body (the word Mollusca means “soft bodied”) usually covered by a shell foot used primarily for movement visceral mass that contains all the internal organs mantle that secretes their shell

27. Mollusks have bilateral symmetry Mollusks Digital Vision/Getty Images

28. Heart digestive systems two openings body cavity with a stomach, and other organs nervous systems eyes other sensory organs simple brains Mollusks

29. Phylum Mollusca Mollusks are classified by the location of their foot Mollusks come in 3 distinct groups: 1. Gastropods- “stomach footed” 2. Bivalves- 2-shells 3.Cephalopods- “head-footed”

30. Phylum Mollusca: Gastropods Gastropods are the only Mollusks to invade land Gastropods feed by scraping algae from rocks with their radula- scraping tongue http://www.youtube.com/watch?v=mLVDwlrSq5U Radula under a microscope

31. Phylum Mollusca: Gastropods Gastropods move using their foot and a trail of mucous Gastropod defense: –Snails: hard shell –Slugs: nocturnal & secrete mucous “Snail trail”

32. Phylum Mollusca: Bivalves Bivalves are filter feeders; they siphon in water & filter out tiny particles for food They move by “clapping” their shells together & are excellent at burrowing in sand & mud Clams, Oysters, Scallops, Mussels http://www.youtube.com/watch?v=H5O1XYZcDh 8http://www.youtube.com/watch?v=H5O1XYZcDh 8

33. Phylum Mollusca: Cephalopods Cephalopods are considered the most intelligent of all Mollusks –Octopi have the largest brain of any invertebrate! –http://www.youtube.com/w atch?v=SCAIedFgdY0http://www.youtube.com/w atch?v=SCAIedFgdY0 Cephalopods feed by catching their prey with their tentacles & bringing it to their strong beak-like jaw Blue ringed octopus Cephalopod beak

34. Phylum Mollusca (Cephalopods) Cephalopods can even change color to mimic other animals or to blend into their background http://www.youtube.com/watch?v=t- LTWFnGmeg&feature=relatedhttp://www.youtube.com/watch?v=t- LTWFnGmeg&feature=related Cuttlefish https://www.youtube.com/watch?v=pgDE2 DOICuchttps://www.youtube.com/watch?v=pgDE2 DOICuc

35. Phylum Mollusca (Cephalopods) Cephalopods move using jet propulsion Other Cephalopods video clips –Humbolt Squid http://www.pbs.org/wnet/nature/episodes/encountering-sea-monsters/video- humboldt-squid-makes-contact/1032/http://www.pbs.org/wnet/nature/episodes/encountering-sea-monsters/video- humboldt-squid-makes-contact/1032/ –Chambered Nautilus –http://www.youtube.com/watch?v=hcyzr3zJol4http://www.youtube.com/watch?v=hcyzr3zJol4

36. Phylum Arthropoda Arthropod means “jointed foot” –Arthro means “jointed; pod means “foot” They are covered with a hard exoskeleton made of protein & chitin –provides stiff frame that supports animal’s body –allows animal to move –acts as suit of armor to protect internal organs and muscles –allows them to live on land without drying out They have a well developed nervous system with a head & brain –most have compound eyes allow them to see images, not as well as we do Compound eyes Antennae

37. Arthropods Segmented body Hard outer skeleton (exoskeleton) Complex nervous system Live on land and in water 1.1 million known species Stomach Made of chitin AbdomenThorax Head Doesn’t grow Brain Sensory organs HeartNo blood vessels Intestines Complex digestive system Open circulatory system

38. Phylum Arthropoda cont’ Arthropods are the largest group of animals on Earth & have the most diversity http://www.youtube.com/watch?v=pTQZAiuDoTg&feature=related http://www.youtube.com/watch?v=pTQZAiuDoTg&feature=related Arthropods are classified by their body parts antennae- feelers that respond to touch, taste, and smell They include, insects, spiders, crabs, centipedes and many more

39. Arthropod Classes  Insecta  Bees  Ants  Grasshoppers  Ladybugs  Arachnida  Spiders  Scorpions  Ticks  Mites  Crustacea  Lobsters  Crabs  Shrimp  Chilopoda  Centipedes  Diplopoda  Millipedes

40. Class Chilopoda centipedes  Numerous body segments  Flat bodies  1 pair of legs per segment  One pair of antennae  Lives on land  Meat eaters  http://www.youtube.com/watch?v=V8gBvud9tts http://www.youtube.com/watch?v=V8gBvud9tts

41. Class Diplopoda millipedes  Numerous body segments  Rounded body  2 pairs of legs per segment  Lives on land  Plant eaters  http://www.youtube.com/watch?v=tn2ZmbOUA2 M http://www.youtube.com/watch?v=tn2ZmbOUA2 M

42. Class Crustacea  shrimp, barnacles, crabs, lobsters nearly all are aquatic and breathe with gills 2 compound eyes, usually on end of stalks  2 body segments  2 pair of antennae  10+ legs  Live in aquatic environments

43. Class Arachnida  Spiders, scorpions, ticks, and daddy longlegs  2 body parts: Cephalothorax (head and thorax and usually 4 pairs of walking legs) and abdomen and eat with their chelicerae  No antennae  No compound eyes; spiders have 8 simple eyes in front of head  Some, like ticks can carry diseases  Primarily lives on land

44. Class Insecta  3 body segments head- 1 pair of antennae and 2 compound eyes, 3 mouthparts w/ 1 pair of mandibles thorax- 3 segments with 1 pair of legs each (6 total), some have wings, no wings, or 2 pairs of wings abdomen  Live in a wide variety of environments

45. Class Insecta cont’ Insects change dramatically throughout their live by a process called metamorphosis Incomplete metamorphosis has three stages: –Egg, nymph & adult Complete metamorphosis has four stages: –Egg, larva, pupa & adult

46. Phylum Arthropoda cont’ Incomplete metamorphosis Complete metamorphosis

47. Echinoderms- “spiny skinned” All are marine animals, most live on the sea floor Examples: sea stars, sea urchins, sea lilies, sea cucumbers, brittle stars, and sand dollars http://www.youtube.com/watch?v=D3W4OCnHyCs http://www.youtube.com/watch?v=D3W4OCnHyCs Most live on the sea floor Have the ability to regenerate http://www.youtube.com/watch?v=d5dOSyaKWTQ

48. Echinoderms Some prey on oysters and other shellfish, some are scavengers, others scrape algae off rocky surfaces

49. Echinoderm Tube feet http://www.youtube.com/watch?v=4IRF-pKVtuU Body contains endoskeleton –Internal skeleton similar to vertebrates –Hard, bony, usually covered with spines Radial symmetry Simple nervous system –Nerve ring around mouth –Sea star has a radial nerve (controls arms) Water vascular system –Water pumps that help animal move, eat, breathe, sense environment –http://www.youtube.com/watch?v=HG17TsgV_qIhttp://www.youtube.com/watch?v=HG17TsgV_qI