SBI3C Name: ______
Fetal Pig Dissection
(pages 256-261)
Instructions: / Checklist:1. / Place your pig on its side in a dissection tray. Using the diagram of the external features of the fetal pig observe the structures on the checklist. Note the anterior (front), posterior (back), dorsal (upper), and ventral (lower) surfaces of the pig. / __ head
__ neck
__ trunk
__ tail
2. / Use a string and a ruler to determine the length of the pig from the tip of the snout to the tip of the tail.
Length in mm: ______
Estimated age (use Fig. 2 on p.257): ______
3. / Locate the paired rows of nipples on the ventral surface of the pig. Note the structures on the checklist. Lift the pig's tail to locate the anus. / __ umbilical cord
__ closed eyelids
__ tongue
__ external ears
__ toes
__ anus
4. / Identify the 2 arteries and 1 large vein in the umbilical cord. / __ umbilical cord arteries
__ umbilical cord vein
5. / Determine the sex of your fetal pig by locating the urogenital opening: in females it's located just ventral to the anus; in males it's located posterior to the umbilical cord; scrotal sac may be visible. (See Fig. 3 on p.257) / __ male?
or
__ female?
6. / Use a pair of scissors, cut through the corners of the mouth from the opening to the posterior. Use the diagram of the mouth to locate the epiglottis. Use a probe to locate the structures listed. / __ epiglottis
__ trachea
__ opening to esophagus
__ teeth
__ tongue
__ hard palate
__ soft palate
7. / Place your fetal pig on its back in the dissecting tray. Use 2 pieces of string to attach the pig's limbs together and the pig to the tray.
Use the diagram shown as your guide.
With a pair of scissors, make a small cut in the abdomen, just in front of the umbilical cord. Insert the tip of the scissors into the cut and then extend the cut along line #1 until you reach the rib cage.
*Don't cut too deep...you may damage the internal organs!*
Cut along line #3, then along line #2.
Lift up the umbilical cord, then cut the umbilical vein and tuck the cord between the hind legs.
Extend cut #3 around to the back, and make similar cuts at #4.
Fold back the flaps of the body wall and pin them to the bottom of the tray. /
8. / Use the following diagram to locate the:
__ liver
__ diaphragm
__ spleen
__ large instestine
__ small intestine
__ end of esophagus
__ stomach
__ pancreas
__ gall bladder /
9. / Make a cut through the esophagus, just below the diaphragm. Gently lift the stomach and intestines up out of the abdomen. Make a second cut through the lowest portion of the large intestine. Remove the stomach and intestines and set down in the tray.
Using the scissors to gently cut away connective tissue, carefully unravel the entire digestive tract.
Measure and record the length of the:
small intestine: ______
large intestine: ______
10 / Identify the... / __ kidneys
__ ureters
__
11 / Using the scissors, extend cut #1 up through the rib cage. Carefully cut the diaphragm to separate it from the rib cage.
Locate the heart and using forceps and a probe, carefully remove the pericardium membrane.
Identify the chambers of the heart and the direction of blood flow.
Make a diagonal incision across the heart and expose the inner chambers. Which chamber has thicker walls?
__ left ventricle
or..
__ right ventricle / __ heart
__ pericardium membrane
12 / Locate and identify the following...
Describe the texture of the lungs.
Describe the texture of the trachea. What is the function of the cartilaginous rings? / __ lungs
__ larynx
__ trachea
When you are finished all of the above, you may continue to work on the dissection to discover other systems... Please write your observations below...