1. Phylum Mollusca Includes over 100,000 species with great variety in appearance and structure include snails, slugs, oysters, clams, octopuses, squid, etc. most have soft bodies protected by a internal or external shell most have bilateral symmetry the body plan of mollusks have four parts: a muscular foot, a mantle, shell and visceral mass

2. foot - used for locomotion, very muscular; used for crawling, burrowing or capturing prey mantle - soft outer layer of body that drapes over animal mantle produces the shell, functions in respiration, waste disposal, and sensory reception mantle cavity houses a gill which extracts oxygen from the water and disposes of fluid wastes radula - extends from the mouth and scrapes up food

3. visceral mass- contains most of the internal organs true coelom houses the heart, reproductive organs, and part of kidney organ systems include digestive tract, circulatory system, and nervous system The three most diverse groups of mollusks include: 1) gastropods 2) bivalves 3) cephalopods

4. Gastropods largest group including snails, slugs, and conchs shell-less or single-shelled mollusks that move by using a muscular foot located on the ventral side piece shells may live in fresh water, salt water, or on land (mantle cavity evolved into a lung instead of a gill)

5. Bivalves include clams, oysters, mussels, and scallops have two shells(valves) held together by a powerful muscles (1 or 2) most are sedentary or sessile, but some may move quickly by clapping its valves together and squirting water muscular foot is used for digging and anchoring

6. Cephalopods include squids, octopi, nautiluses, and cuttlefishes soft-bodied mollusks in which the head is attached to a single foot; the foot is divided into tentacles or arms most complex of the mollusks; built for speed and agility have external shells(nautilus), internal shells(squid), or no shells(octopus) well developed sense organs and large brains; some have been trained

7. Ecology of Mollusks symbiotic relationships with algae and parasites environmental monitors- filter water and are used as pollution monitors subject of research because they never develop cancer

8. Phylum Arthropoda over 1,000,000 types of segmented animals considered to be the most successful phylum of animals that have ever existed include crayfish, lobsters, crabs, barnacles, spiders, ticks, and insects all have jointed appendages (Greek arthron means joint) such as legs and antennae all have hard exoskeleton (made of chitin) for protection and support; must shed exoskeleton (molt) to grow open circulatory system, complete digestive system, nervous system, true coelom

10. (legs, antennae)

11. (Segmentation) Body formed of several distinct segments: cephalothorax - fused head and thorax segments head - sensory antennae, eyes, jointed mouthparts thorax - 2 pincers & 4 pair of legs for walking abdomen - swimming appendages

12. Arthropods may be divided into 5 main groups based on the number and structure of their body segments and appendages (esp. mouthparts) 1) horseshoe crab - considered a “living fossil” -only surviving member of arthropods that were abundant in the sea 300 million years ago -gill bearing, marine animals

13. 2) arachnids - include scorpions, spiders, ticks, and mites - most live on land - scorpions are nocturnal hunters, carnivores, tip of tail bears a poisonous stinger - spiders are very diverse group, active during the daytime, spinnerets used to spin complex webs; 4 pair of legs; complex nervous system

14. - mite - (dustmite) - found in our homes thousands may be found in a few square centimeters of carpet or in one dustball do not cause disease, but may cause allergies

15. 3) Crustaceans - all aquatic; include lobsters, crayfish, crabs, shrimp, and barnacles Barnacles are sessile marine crustaceans that live in a shell; bottom-dwellers jointed appendages project from shell and capture small food particles; no eyes, gills, heart, or blood vessels

16. 4) millipedes & centipedes - segments make them look like annelids with paired legs on each segment Millipedes - wormlike landlubbers, eat decaying plants, 2 pair of legs on each body segment Centipedes - terrestrial carnivores; 2 poison claws; 1 pair of long legs on each body segment

17. 5) Insects - represent 75% of all known animal species; over 1,000,000 species known; extremely successful Most have three-part body: head, thorax, and abdomen have sensory antennae, 2 eyes, several mouthparts, 3 pair of legs, 1 or 2 pair of wings most go through metamorphosis - series of changes during which young insects develop into adults (changing shape and form)

18. Complete Metamorphosis -Bees, moths, butterflies -Animals hatch into larvae that look nothing like adults -Feed in completely different ways Molt several times then change into a pupa (stage in which body completely remodeled)

19. Incomplete Metamorphosis Chinch bug, grasshoppers Immature forms look like adults Nymphs lack sex organs and other adult structures

20. Insects and Humans (ecology) Insects can be both beneficial and harmful Harmful termites destroy wood bees sting moths eat wool locusts eat crops Beneficial pollination of crops honey silk

21. Echinoderms- “spiny-skinned” Echinoderms are coelomates, and are segmented examples include sea stars (starfishes), sea urchins, sand dollars, sea cucumbers, and sea lilies. 6,000 species of echinoderms; they are all marine. echinoderm adults have radial symmetry, but they evolved from ancestors that were bilaterally symmetrical free-swimming, bilaterally symmetrical larvae that metamorphose (change as they mature) into radially symmetrical adults very simple nervous system to coordinate movement of arms (no head or brain) most have spiny surface which comes from extensions of its endoskeleton Gas exchange is done with numerous tiny gills that extend from the surface of the skin.

22. Echinoderms reproduce sexually and asexually sexual reproduction-sexes are separate and gametes are expelled into the water. the gonads are large due to the necessity of releasing large numbers of gametes into the marine environment fertilization occurs externally (in the water) asexual reproduction occurs if an arm is cut off; the sea star can regenerate its missing arm (ray) the fragmented piece can grow back the rest of its body (as long as part of the central disk is still attached) through the process of fragmentation

23. Ampulla Radial Canal Spine Cross Section of Ray

24. 1 4 5 6 3 2 Stone Canal

25. - Echinoderms use a water vascular system for movement, circulation and respiration -consists of a water-filled ring canal that branches into radial canals & tube feet found in each arm the ampulla is found on top of each tube foot and helps force water through the system which causes the foot to extend each foot has a suction-cuplike end used for movement and feeding

26. -Complete digestive system includes a mouth and an anus - mouth located centrally on its undersurface Carnivorous - when eating a clam or oyster, it grips the shell with its tube feet and positions its mouth next to the opening between the two valves of the shell the stomach pushes out through its mouth, enters the mollusk, and digests the soft parts

27. - sea urchins and sand dollars are sphere shaped and have no arms - spines are used for protection and movement - tube feet also used for movement in the sea urchin - tube feet in sand dollar do not have suction cups and are only used for respiration - solid, internal shell

28. Sea cucumbers - bilateral symmetry, no arms, wimpy endoskeleton made of scattered calcium plates - some have tentacles for grabbing food Defense - shoots out long, thin, sticky, poisonous tubules from anus some will eject entire digestive system and regenerate it in a few days

29. Ecology of Echinoderms Echinoderms control population changes of other marine life –Sea urchins control algae –Sea stars hunt clams and coral crown-of-thorns (a sea star) feeds on only coral it has destroyed part of the Great Barrier Reef of Australia- one of the largest reef systems in the world

33. 1 4 5 6 3 2 Stone Canal