lab practical (Shark)

Rostrum

The pointed snout at the anterior end that streamlines the body to reduce drag and houses electroreceptors (ampullae of Lorenzini).

Mouth

Ventrally located opening lined with rows of replaceable teeth used for capturing, biting, and tearing prey.

Eyes

Lateral sensory organs that provide visual perception in various lighting conditions.

Fins

Structures that control motion and stability; pectoral fins generate lift and steering, dorsal fins prevent rolling, and the caudal fin produces forward propulsion.

Lateral line system

Fluid-filled canals running along the body containing mechanoreceptors that detect vibrations, pressure changes, and movement in the surrounding water.

Cloacal opening

Common external exit cavity located between the pelvic fins for the excretion of digestive waste, urine, and reproductive gametes.

Gills

Feathery, highly vascularized internal structures that absorb dissolved oxygen from incoming water and release carbon dioxide.

Heart

Multi-chambered muscular pump that receives deoxygenated blood from the body and pumps it forward into the gills for reoxygenation.

Liver

Large, oil-filled organ that produces bile, filters toxins, stores energy, and provides buoyancy (since sharks lack a swim bladder).

Stomach

J-shaped muscular organ where ingested prey is stored and broken down by gastric acids and enzymes.

Intestine

Completes digestion and absorbs nutrients into the bloodstream; contains an internal spiral valve that increases surface area and slows food passage.

Pancreas

Glandular organ that secretes digestive enzymes into the intestine and produces hormones to regulate blood sugar levels.

Gonads

Primary internal reproductive organs—ovaries in females (producing eggs) or testes in males (producing sperm)—responsible for gamete and hormone production.