Are you Shark Smart?

1. Are you Shark Smart? Shark Anatomy

2. Shark Skeleton • Made of calcified cartilage • Spinal Nerve Cord Carries nerve impulses • Vertebrae - Form the shark’s backbone of cartilage

3. External Features of the Shark • The backbone side of the shark is known as the DorsalSide • The belly side of the shark is known as the Ventral Side • Anterior means towards the head • Posterior means towards the tail

4. Male or Female? The male shark has claspers, the female shark does not

5. What do the various fins do? • Dorsal fins: Help the shark maintain stability (unpaired) • 2nd Dorsal fin: Stabilizes the shark’s forward swimming motion (unpaired) • Pectoral fin: helps the shark move up or down or left or right (paired) • Pelvic fin: Helps the shark change course (paired) • Anal fin: Offers stability and an extra bit of turbulent push (unpaired) • Caudal Fin: Helps with movement

6. Shark Sensors • Ampullae's of Lorenzini: Pores which help locate prey • Lateral Line: sharks sense of distant touch

7. Shark Senses • Eyes – similar to the eyes of man • Nictitating Membrane - protective membrane that covers the eye • Nostrils – help the shark detect blood and injured flesh at great distances

8. How does the shark breathe? • Gill Slits: Water taken into the mouth passes over the gill slits so oxygen can be removed • Spiracle: Help bring water into the mouth for breathing when the shark’s mouth is closed

9. Shark Teeth On the skin and in their mouth! • Denticles:Tooth-like projections on the skin. They help with protection and movement • Shark Teeth: Several rows; size and shape varies with the type of shark

10. Shark Internal Anatomy Upon incision of the belly from the pelvic fins to the pectoral fins, the first organ encountered is the liver. The liver of sharks occupies most of the body cavity. This large, soft and oily organ can comprise up to 25% of the total body weight.  The liver serves two functions within the shark: • Energy store - since all fatty reserves are stored here.  • Hydrostatic organ - Oils that are lighter than water are stored in the liver. This decreases the density of the body providing buoyancy to counteract the sinking tendency of sharks.

11. Digestive System • Esophagus - Tube leading to the stomach • Stomach - “J” shaped organ –from here food passes into the intestine • Intestine –This is found posterior to the stomach. Part of the intestine is marked by rings. The intestine has a spiral valve. • Cloaca – where waste material leaves the body • Kidney - excretes liquid waste • Anus - where waste leaves the body

12. Internal Organs • Spleen - dark, triangular structure found near the posterior end of the stomach. It helps to filter the blood of dead blood cells. • Pancreas - Whitish organ found on the ventral side of the stomach. Further breaks down food. • Gall Bladder - Small organ near the stomach which stores bile.

13. Cardiopulmonary System • Heart: • Two chambered heart • Blood enters one chamber at a time. • Gills: • Oxygen–rich water comes in through the mouth • Gills filter out the oxygen and release the water and waste gases.

14. Reproductive System • Ovary - 2 round female organs which produce eggs • The ova (eggs) form in the ovaries of the female shark and move down the oviducts to the uterus.

15. The Brain Partial List of Functions: • Cerebellum is in charge of body movement • Hindbrain processes most sensory information and moves the head • Tectum integrates sensory information • Olfactory lobes are for the sense of smell • Diencephalon regulates hormones and some behaviors • Forebrain coordinates sensory information

16. Are you ready for dissection?