Marine Conservation Lab Report
Instructions: In the Marine Conservation lab, you will complete a necropsy to observe shark anatomy and determine the cause of death of a dogfish shark. Record your observations in the lab report below. You will submit your completed report.
(30 points possible)

Name and Title  (1 point)
Victoria Arruda
04/24/2017
Marine Conservation Lab.
Objective(s)  (2 points)
Determine the death cause of the shark and identify how human activities impact marine life and analyze this impact.

Hypothesis  (2 points)
You read about some potential threats to this type of shark. You are about to perform a necropsy to determine the cause of death. Make a prediction of what you think may have caused the death of this shark:
If we throw trash in the ocean then it will cause the death of sharks.

Procedure
In this lab, you will:
complete a virtual necropsy of a shark to determine the cause of death
identify how human activities affect marine environmental quality for the shark population
analyze the impact habitat destruction and pollution can have on an aquatic ecosystem and how it threatens the survival of some species

Data and Observations  (15 points)

Specimen History
Description
Observations
Species
Spiny Dogfish
Coloration
Grayish brown
Length
110cm (Dogfish Shark usually 1-1.6meters )
Gender
Female

Necropsy Findings
Structure
Identify the function of each organ
Dorsal fins
Stabilize the animal against rolling and to assist in sudden turns.
Caudal fin
Is used for propulsion.
Claspers
Structure used in mating, serve as intromittent organs.
Forebrain
The two cerebral hemispheres are the rounded lobes of the anterior brain.
Midbrain
The optic lobes are a pair of prominent bulged structures.
Hindbrain
The cerebellum is oval-shaped, and the medulla oblongata is the elongated section that leads to the spinal cord.
Gills
The gills are the respiratory organs of the shark. They are composed of gill lamellae, blood vessels, and supporting structures.
Heart atrium and ventricles
Arteries run from the heart to the gills, bringing deoxygenated blood. Oxygen diffuses from the ventilating water current, flowing over the gills into the blood.
Kidneys
The kidneys are flattened, darkly colored organs along the entire length of the body cavity. A tough white glistening strip of connective tissue is found between the kidneys in the midline.
Ovaries
Two cream-colored organs, one on each side of the mid-dorsal line. Eggs travel into the oviducts when they are ready to be fertilized.
Oviducts
Elongated tubes that lie dorsal and lateral along the body cavity. The distal end of the oviduct forms the uterus.
Uterus
The enlarged caudal end of the oviduct. It is here that eggs develop.
Liver
The liver is the largest organ in the body cavity. It is composed of three lobes, two large and one smaller
Gallbladder
The gallbladder is located within the smaller lobe. The gallbladder stores the bile secreted by the liver. Oil in the liver helps the shark maintain neutral buoyancy while swimming.
Stomach
This J-shaped organ is composed of a cardiac portion, which lies near to the heart, and a limb portion that continues to the main body.
Pancreas
The pancreas is divided into two lobes and produces digestive enzymes to break down fats.
Spiral intestine
Located cranially from the duodenum, it adds surface area for digestion.
Rectum
This is the end of the digestive tract and stores solid wastes.

Laboratory Results
Tissue Sample
Result
Cerebral spinal fluid
Normal
Heart
Normal size and color
Gills
Normal
Kidney
Normal
Liver
Toxicology shows some elevated levels of methyl mercury
Stomach
Plastic present

Conclusion  (10 points)
Your conclusion will include a summary of the lab results and an interpretation of the results. Please answer in complete sentences.
What are some of the threats to dogfish sharks?
The dogfish shark can be eaten by other shark species or whales, so they are a threat to the dogfish. Also, pollution such as debris and oil spill can be a threat to dogfish. Overfishing can also play a role on that because it can overfish the shark itself or smaller fishes that serve as food.
What abnormalities, if any, were detected in the necropsy results? How may these factors have contributed to the shark's death?
There was plastic present in the shark's stomach