Shark Lab

Activity 4: Circulatory System

Return to Laboratory Exercise


Click on any photograph for an enlarged view in a separate window.


Circulatory Anatomy of the Dogfish Shark

Examine the bottom view photographs of the skinned spiny dogfish shark by clicking the blue lettered links in the column to the right. The specimen in the photographs was prepared by removing the skin and the ventral musculature over the pericardial cavity. A membrane was removed to expose the heart and some of its major blood vessels.

The pericardial cavity is the upper portion of the body cavity. It is much smaller than the lower cavity, which contains the digestive organs.

The pericardial cavity is located anterior to the transverse septum and contains the heart and the major blood vessels leading to and from the heart.

The pericardium is the membrane lining the inner walls of the pericardial cavity.

Shark Pericardial Cavity

Labeled Pericardial Cavity

Examine the photographs of the shark's heart by clicking the blue lettered links in the column to the right.

The ventricle is the thick muscular walled cavity that pumps blood through the conus arteriosus to the gills and the body. The conus arteriosis contains a series of semilunar valves that direct the blood flow.

The atrium is thin-walled with two lateral bulging lobes. It pumps blood to the dorsal ventricle.

Shark Heart

Labeled Heart

Examine the bottom view photographs of the shark's heart and cardinal sinuses by clicking the blue lettered links in the column to the right.

Blood enters the heart through the sinus venosus which drains into the atrium.

The posterior cardinal sinuses receive blood from the posterior parts of the body and drain through the common cardinal veins into the sinus venosus.

Shark Sinuses

Labeled Sinuses

Examine the photographs of the shark's ventral aorta by clicking the blue lettered links in the column to the right.The specimen in the photographs was prepared by removing the ventral hypobranchial muscles and connective tissues until reaching the lower jaw. The conus arteriosus was traced anteriorly following the major branching blood vessels.

The anterior end of the conus arteriosus continues foward as the ventral aorta. It gives off five pairs of afferent branchial arteries which carry deoxygenated blood from the heart to the gills.

The afferent branchial arteries pass laterally from the medial ventral aorta carrying deoxygenated blood to the gills. These afferent vessels enter the interbranchial bars and serve the holobranchs of the gill arches.

Shark Ventral Aorta

Labelled Ventral Aorta

Examine the photographs of the male shark's efferent branchial arteries by clicking the blue lettered links in the column to the right. The specimen in the photographs was prepared by removing the mucous membrane from the roof of the mouth and pharynx.

The efferent branchial arteries serve to return oxygenated blood from the gills. This blood is then distri bused to all parts of the body. Four pairs of arteries may be seen arising from the gills and uniting in the midline to form the median dorsal aorta.

The efferent branchial arteries give off many branches. These carry oxygenated blood to the more anterior parts of the shark's body.

The four pairs of efferent branchial arteries join at the dorsal midline to form the large dorsal aorta. The dorsal aorta passes posteriorly bringing oxygenated blood from the gills to virtually every part of the shark's body.

Shark Dorsal Aorta

Labelled Dorsal Aorta

Examine the photographs of the female shark's efferent branchial artery by clicking the blue lettered links in the column to the right. The specimen in the photographs was prepared by carefully dissecting to reveal the source of each efferent branchial artery in the gill lamallae of the gill pouches.

The efferent collector loops encircle each of the first four gill pouches.

Shark Efferent Artery

Labeled Efferent Artery

 Examine the photographs of the shark's collector loop by clicking the blue lettered links in the column to the right.

Adjacent collector loops are connected to one another by branches which pass through the interbranchial septa.

Shark Collector Loop

Labeled Collector Loop


Click the radio button next to the appropriate answer for each question:


1. Which of the labelled arrows is pointing to the Pericardial Cavity?

a. b. c. d.


2. Which of the labelled arrows is pointing to the Ventricle?

a. b. c. d.


3. Which of the labelled arrows is pointing to the Sinus Venosus?

a. b. c. d.


4. Which of the labelled arrows is pointing to the Cardinal Sinuses?

a. b. c. d.


5. Which of the labelled arrows is pointing to the Ventral Aorta?

a. b. c. d.


6. Which of the labelled arrows is pointing to the Afferent Branchial Arteries?

a. b. c. d.


7. Which of the labelled arrows is pointing to the Dorsal Aorta?

a. b. c. d.


8. Which of the labelled arrows is pointing to the Efferent Branchial Arteries?

a. b. c. d.


9. Which of the labelled arrows is pointing to the Efferent Branchial Arteries?

a. b. c. d.


10. Which of the labelled arrows is pointing to the Collector Loop?

a. b. c. d.



You can:

 

 Return to Laboratory Exercise

 

 Go to Activity 1: Shark External Anatomy

 

 Go to Activity 2: Shark Digestive Anatomy

 

 Go to Activity 3: Shark Respiratory Anatomy

 

 Go to Activity 5: Shark Urogenital Anatomy

 

 Go to Activity 6: Shark Nervous Anatomy