Shark Dissection Project

By: Sebastian Diaz, Juan Morales,

Natalie Robb, Teri Thornhill

For this project our group was to learn about the dogfish shark inside and out. We got pretty attatched to our shark and named him Lenny.With this project, we were to look at all the systems including the muscular system, digestive system, circulatory system, and nervous system. We were also supposed to learn about the external anatomy of Lenny the shark. So welcome to our page.

Eye

The following are the names and functions of the Eye:

Cornea- Is the external coat of the eye covering the iris and the pupil.

Iris- Controls the size of the pupil.

Lens- Controls most of the light that enters the eye.

Retina- Receives the image produced by the lens and is sensative to light.

Nervous System

The following are the names and functions of the Nervous System:

Olfactory Bulb- Sends signals to the Olfactory Tract and sense of smell.

Olfactory Tract- It is a pathway to the sense of smell.

Cerebrum- This determines how the shark acts.

Optic Lobe- Where the primary visual centers are.

Cerebellum- Controlls coordination and balance.

Medulla Oblongata- Sends nerve signals back and forthfrom the brain to the spinal chord.

Circulatory System

The following are the names and functions of the Circulatory System:

Sinus Venosus- Pumps blood.

Atrium- Pumps blood into the main pumping chamber.

Ventricle- Collects blood that is pumped from the atrium.

Conus Arteriosus- Where the pulmonary artery originates.

Visceral Pericardium- It separates circulatory system from the digestive systems .

Caudal Artery- The part of the dorsal aorta of a vertebrate that passes into the tail.

Caudal Vein- Takes the blood to the heart.

Digestive System

The following are the names and functions of the Digestive System:

Mouth- Where food enters the digestion system.

Esophagus- Used to transport food from the mouth to the cardiac stomach.

Cardiac Stomach- Digests food, which then travels to the pyloric stomach.

Pyloric Stomach- Second stomach that breaks the food down further.

Rugae- Gives the stomach greater surface area.

Liver- Makes bile, which is used for digestion.

Cardiac Sphincter- Separates cardiac stomach from pyloric stomach.

Pyloric Sphincter- Transfers food into small intestine from pyloric stomach.

Mesentery- Holds digestive organs together.

Gall Bladder- Stores extra bile.

Common Bile Duct- Transfers bile to digestive organs.

Pancreas- Makes digestive enzymes.

Duodenum- Small tube in the intestines that the gall bladder and pancreas empty in to for further digestion.

Ileum- Absorbs nutrients from food.

Spiral Valve- Lets the illeum increase in size.

Colon- Absorbs water.

Rectum- Absorbs water.

Cloaca- The digestive tract's exit.

Skeletal System

The following are the names and functions of the Skeletal System:

Rostrum- Supports the snout.

Nasal Capsule- It is a sensory organ.

External Naris- Used for smell.

Orbital Cavity- Where the eye is located.

Labial Cartilage- Helps open\close the upper jaw.

Meckel's Cartilage- Helps open\close the lower jaw.

Basals- Helps the pectoral fins rotate\move.

Radials- Supports the fin.

Neural Spine- Helps support the spine.

Centrum- Connects vertebrae.

Neural Arch- Supports caudal fin.

Muscular System

The following are the names and functions of the Muscular System:

Dorsal Longitudinal Bundles- help with movement from side to side and up and down.

Ventral Longitudinal Bundles- used for movement

Lateral Longitudinal Bundles- aid in movement

Myotomes- groups of muscles Epihyoidean- Aids in lifting the rostrum.

Adductor Mandibulae- Is the main muscle used for closing the jaw.

Intermandibulae- Assists in jaw closing. Coracoarcual- Helps with swallowing.

Levator of Fin- Helps lift the fin.

Depressor of Fin- Helps lower the fin.

External Anatomy

The following are the names and functions of the External Anatomy:

Eye- Used for seeing.

Eyelid- Closes over the eye to protect it during attack.

Nostril- Used for smell.

Mouth- Used for eating.

Spiracle- It is the first gill slit and is used for breathing.

Gill Slits- Used for breathing.

lst Dorsal Fin- On the dorsal side closest to the head. Used for balance, swimming and a little bit of steering.

2nd Dorsal Fin- Same as the first dorsal fin.

Pectoral Fin- Used for direction and swimming.

Pelvic Fin- Used for stabilization.

Claspers- Only on male sharks and are used for sperm transfer during mating.

Caudal Fin- Used for movement from side to side.

Rostrum- Streamlines it and helps with speed.

Lateral Line- Used for detecting water movement.

Cloaca- It is the exit from the digestive track and is the opening for sex organs.

Dorsal Spines- Used for protection.