Upward Bound Fetal Pig Dissection Day 4
Objectives:
1.Identify important external structures of the fetal pig.
2.Identify major structures associated with a fetal pig's digestive and cardiovascular systems.
Materials:
same preserved fetal pig
dissecting tools
Directional Planes
Ventral: Stomach side (ventre)
Dorsal: Back side (think dorsal fin)
Medial: Towards the middle
cleanup materials
Anterior: Toward the head (leading side)
Posterior: Toward the rear (trailing side)
Lateral: Towards the sides
Part 1: Complete Day 3 Procedures
1. Complete the procedures you did not get to on Day 3. Use your lab sheet from Days 2 and 3
to identify each of the following structures in the pig:
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Tongue
Salivary Glands
Papillae
Soft palate
Hard palate
Esophagus
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Liver
Small Intestine
Duodenum
Ileum
Large Intestine
Cecum
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Gall bladder
Bile duct
Pancreas
Mesentery
Rectum
Anus
Check In: Show Mr. Spotts or Mr. Biyi your completed Day 3 lab guide before proceeding on
to Part 2.
Part 2: Circulatory System
2. Locate the heart. It is covered by a thin tissue called the pericardium. Remove this membrane
to study the heart.
3. Pigs, like all mammals, have four-chambered hearts. The right side of the heart pumps blood
to the lungs, while the left side of the heart pumps blood to all other parts of the body. Locate the
right and left sides of the heart.
Check In: Does the left or right side of the pig heart have more cardiac muscle?
Explain your answer
4. Each side of the heart has an upper and a lower chamber. Upper chambers are called atria and
receive blood, while lower chambers are called ventricles and pump blood out of the heart.
Locate the right and left atria and ventricle.
5. Notice that the surface of the heart is covered with blood vessels. These are part of the
coronary circulation, a set of arteries and veins whose only job is to nourish the heart tissue.
Blockage in these vessels causes heart attacks.
Check In: What is the function of blood in the body?
6. Anterior to the heart, locate another large vein that enters the right atrium. This vein, the
anterior vena cava, brings blood to the right atrium from the anterior part of the body.
7. Now lift the heart to view its dorsal surface. Observe the posterior vena cava that carries
blood from the posterior part of the body and empties it into the right atrium.
8. Find the pulmonary artery that leaves the right ventricle. After birth, this vessel carries blood
to the lungs. However, in a fetus, a shunt called the ductus arteriosus allows fetal blood to
bypass the lungs and go directly to the aorta, the largest artery of the body.
Check In: Why doesn’t the pig need a ductus arteriosus after it is born?
9. Locate the pulmonary veins that enter the left atrium. After birth, these vessels carry
oxygenated blood from the lungs to the heart.
10. Identify the aorta, a large artery that transports blood from the left ventricle. Many arteries
that carry blood throughout the body branch off of the aorta.
11. Remove the heart by using the scissors to sever the blood vessels attached to it.
12. Hold the dorsal and ventral surfaces of the heart with your thumb and forefinger and rest the
ventricles on your dissecting tray. With a scalpel, cut the heart into dorsal and ventral halves. It
is important to make a “front half” and “back half”.
13. Study the internal features of these chambers and note where vessels leave or enter each
chamber. Locate the valves between each atrium and ventricle. These structures prevent blood
from flowing backward in the heart.
Check In: Contrast the valve on the left side of the heart with the valve on the right side.
Check In: Make a comparison between the fetal pig heart and the fully formed adult pig heart.
Besides the sizes, what are two differences between them?
CLEAN UP PROCEDURES
1. Remove the tie strings from one side of the pig. Leave them on the other side to make it easier
to re-tie the pigs tomorrow.
2. Inventory and wipe all your tools down
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2 teasing probes
2 scissors
1 scalpel
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1 eyedropper
1 forceps
1ruler
3. Put all your clean tools in your labeled plastic case.
4. Wipe down your table and make sure everything is put away.
*NOTE: All parts of the pig that were separated from the main body (i.e. bits of
mesentery, etc.) should be put in the “pig parts bag” and thrown away.
Analysis Questions
1. What are three things that all cells in the body need in order to survive?
2. Why do you think the heart is covered by smaller blood vessels?
3. Label the parts of the heart.
A. _____________________
B. _____________________
C.______________________
D.______________________
E.______________________
F.______________________
G.______________________
H.______________________
I._______________________
4. How do the circulatory system and the digestive system work together to get the body’s
cells everything they need to survive?
5. Completely fill out the diagram from the Day 3 lab packet.
6. What are four additional questions you have about body systems after four days of fetal
pig dissection?
7. In addition to the fetal pig dissection, what are 12 different skills or topics that will be
covered on your cumulative final exam next Tuesday?
1. ___________________________
7. ___________________________
2. ___________________________
8. ___________________________
3. ___________________________
9. ___________________________
4. ___________________________
10. ___________________________
5. ___________________________
11. ___________________________
6. ___________________________
12. ___________________________