1. Marine Biology Outcome: Explain the complexities of cartilaginous fishes anatomical advancements that allow them to efficiently hunt, detect prey and avoid predation. Drill: Recall the four chordate structure and briefly list what they do (words/drawing).

2. Last Class We identified the four characteristics of a chordate… We organized the classifications of fish… Let’s review:

3. Today! Today we will learn how chordate complexities have evolved to give sharks the anatomical structures that make them efficient predators. the importance of having or not having a swim bladder the importance of the ampullae of Lorenzini the importance of the lateral line system the overall anatomy/defenses of sharks, rays, and skates

4. K. Animalia P. Chordata C. Agnatha Hagfish and Lamprey Only existing representatives of the jawless fish Hagfish -Bottom-dwellers -Predator/Scavenger -Live only in the ocean -Cartilage structure -No paired fins -Defense: Slime Glands Lampreys -Filter feed as juveniles -Parasitic as adults -Adult life in ocean -Spawn in freshwater -Cartilage structure -No paired fins

5. Fish Fins Caudal fin-- provides thrust Pectorals-- act as rudders for turning, breaking, balancing Pelvic fins-- mostly controls pitch Dorsal/anal-- control roll

6. K. Animalia P. Chordata C. Chondrichthyes Sharks - Skeletons composed completely of cartilagecartilage - Control buoyancy with their nitrogenous liver (squalene) - Detection of a drop of blood in one million parts H 2 O - Hammerhead sharks olfactory on each side of “hammer” - Lateral line system detects prey/predators - Ampullae of Lorenzini electrical impulses - Osmoregulation by retaining nitrogenous wastes

7. Lateral Line System The lateral line system, found in many fishes and in some aquatic amphibians, is sensitive to differences in water pressure. A swimming fish sets up a pressure wave in the water that is detectable by the lateral line systems of other fishes.

8. Lateral Line System

9. Ampullae of Lorenzini The Ampullae of Lorenzini are small vesicles and pores that form part of an extensive subcutaneous sensory network system. These vesicles and pores are found around the head of the shark and are visible to the naked eye. The ampullae detect weak magnetic fields produced by other fishes, at least over short ranges. This enables the shark to locate prey that are buried in the sand, or orient to nearby movement.

10. Ampullae of Lorenzini

11. Nare Eye MouthPectoralPelvicAnal Lateral Line CaudalDorsal Gills

14. K. Animalia P. Chordata C. Chondrichthyes Rays and Skates - Flattened bodies with greatly enlarged pectoral fins - Reduced dorsal and caudal fins - Eyes and spiracles on their dorsal (top) side - Gill slits on their ventral (bottom) side - Defense of electric ray is a volt up to 220 - Defense for skates/rays is venomous dorsal fin spine/tail

20. Recap!! Why do sharks move their heads from side to side as they swim? What is the function of the Ampullae of Lorenzini? Sharks do not have a swim bladder. What adaptations do they have to prevent sinking? What is a nictitating membrane? Do humans have one? Distinguish the difference between male and female sharks. Why do skate and rays have spiracles? Skates and rays seem so harmless, yet there are warnings against swimming with them. Describe the defense mechanisms of skates and rays. What are the main differences between skates and rays?

21. Worksheet on Sharks! We will be discussing the key features before you leave today and this worksheet will be due before you leave! Next class we will be discussing Bony Fish Anatomy

22. Nov 6 th, 2015Marine Bio Drill: Sharks are the top predators in the ocean. Their adaptations help them detect and capture prey. Describe these adaptations and how they enable sharks to be efficient predators.

23. Nov 9 th, 2015Marine Bio Outcome: Today I can determine the differences between cartilaginous and bony fish by comparing their external and internal structures.

24. Recaping! Chondrichthyes (sharks)

25. Recaping! Chondrichthyes (rays) 1 2 3 4 5 6 7 89

26. K. Animalia P. Chordata C. Osteichthyes Bony Fish (Salmon & Coelacanths)Coelaanths Skeleton composed of bones Lateral line, as in Chondrichthyes, detects prey/predators Ampullae of Lorenzini is only found on Chondrichthyes Operculum is the covering to protect the gills Buoyancy is maintained by a swim bladder, in some cases Bony fish have many other adaptations and coloration patterns that we will discuss in a later class.

27. Swim Bladder Swim Bladder - A swim bladder is a gas filled bag that sits in a fish's body cavity to control buoyancy. Only Ray-finned fish possess a swim bladder.

28. Swim Bladder

32. Classifying the Coelacanth Today you will read the fish anatomy paper and take the knowledge from the passed two classes and put it to work You will use the computer, your book and brain to determine if the Coelacanth is classified correctly as an Osteichthyes by comparing it to a bull shark (Chondrichthyes) and eel (Osteichthyes) A final poster will be created comparing the three types of fish and your explanation and answers to the 5 questions will be written on the back of the poster

33. Reproduction

34. Gills Fish extract oxygen from the water via their gills Gill slits are covered by an operculum to protect them When water moves over the gills a countercurrent is created

35. OsmoregulationOsmoregulation (p 240) Fish need to maintain homeostasis by regulating the amount of water in their tissue by osmoregulation. Freshwater fish have more salt inside the fish so they don’t drink water because water moves into them… they have dilute urine Saltwater fish more salt outside the fish so they do drink water because they lose water to the environment… they have concentrated urine.