Living Environment Fetal Pig Lab/Edwards-Knox Central School
Name ______________________________
Information to Understand Prior to the Dissection Lab
Before beginning a dissection, it is important to have an understanding of some of the
basic directional terminology associated with the dissection of specimens. Some of these
terms include proximal, which means toward the body, and distal, which means to move
away from the body. Other important anatomical directions are indicated below.
Key Anatomical Directions
Dissection Equipment
The pictured dissection equipment from left to right are (1.) dissecting scissors which
are used to cut through tissue , (2) a teasing or dissection needle which used to pull apart
muscle tissue, (3) a scalpel, which is a knife used to slice through and cut tissue, and (4)
forceps, a surgical instrument that resembles a pair of tweezers and can be used in
surgery for grabbing, maneuvering, or removing various things within or from the body
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Proper safety procedures when working with dissection tools and specimens is of greatest
importance. Some safety rules to engage in when dissecting specimens are as follows.
Dissection Safety Rules
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Follow all instructions given by your teacher.
Inform your teacher of any illness as a result of exposure to chemicals used in
specimen preparation.
Avoid contact with preservative chemicals. Rinse the specimens completely before
dissection.
Know where the eye-wash fountain is if needed.
Wear safety goggles to prevent the splashing of any chemicals into the eyes.
Properly mount dissection specimens to dissecting pan. Do not dissect a specimen
while holding it.
Handle scalpel or razor blade (safety edged) with extreme care.
Always cut away from your body and away from others.
Never ingest specimen parts.
Never remove specimens or specimen parts from the classroom -- until the dissection
is completed all parts of the dissection must remain within the dissecting pan.
Properly dispose of dissected materials.
Store specimens in as directed by your teacher.
Clean up the work area and return all equipment to the proper place when the
dissection is completed.
Wash hands after each dissection.
Note: 40% your grade for this lab will be based upon your
dissection skills and behaviors
Evaluation (0 = lowest 5=highest)
Quality of Dissection (well executed, specimen is in
good shape)
Identification of Structures
Lab Behavior/Attitude/Following Instructions
Cooperation with Cleanup
Participation
Total Manipulative Grade =
0 1 2 3 4 5
0
0
0
0
1
2
2
2
2
4
4
4
3
6
6
6
4
8
8
8
5
10
10
10
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The period of pregnancy or gestation for pigs is 112-115 days (3 months, 3 weeks, 3
days) and each female may produce a litter of 7-12. As the period of development
proceeds, the pig embryos get longer, so an approximate age may be calculated from the
length. (from Odlaug: Laboratory Anatomy of the Fetal Pig, William C. Brown, 1955.)
Average Development Rate of the Fetal Pig
Time from Conception
21 days
35 days
49 days
56 days
100 days
114 days (birth)
Pig Length in mm
11 mm
17 mm
28 mm
40 mm
220 mm
300 mm
1. Use the data above to graph the developmental rate of the fetal pig on the
graph provided. Remember to use a proper scale, title your graph, label your axes,
and key your graph. Surround each of your plotted points with a circle and
connect the points.
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2. During which third of the period of the pregnancy of the fetal pig does the
most growth occur? Use the data in the preceding graph or chart to support
your answer.
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3. Complete the following table describing anatomical directions.
Anatomical Direction
Meaning
dorsal
ventral
anterior
posterior
4. Carefully draw and label four different dissection instruments in the space below.
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5.
Complete the following table.
Dissection Instrument
Purpose of Dissection Instrument
scalpel
forceps
dissection scissors
dissection pins
teasing needle
6. Complete the table below.
Safety Rule
Specifically why is this rule important?
(do not just say so you don't get hurt or any
other vague answer)
Wear safety goggles
Always cut away from your
body and away from others
Avoid contact with preservative
chemicals and wear gloves
Do not dissect a specimen while holding
it. Always properly secure your specimen
to the dissecting tray.
Properly dispose of specimens
Clean up your area as directed by the teacher
and wash your hands
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Part II. Dissecting the Pig
1. Put on your lab goggles and apron.
2. Obtain your dissecting equipment and pig from the cart.
3 Place the fetal pig ventral (bottom) side up in the dissecting tray.
4. Tie a string securely around a front limb. Run the string under the tray, pull it
tight, and tie it to the other front limb. Repeat this procedure with the hind limbs
to hold the legs apart so you can examine internal structures.
5. Study the diagram below. The dashed lines numbered 1-4 show the incisions that
you will make and the order you will make them in. Be sure to keep the tips of
your scissors pointed upward because a deep cut will destroy the organs below.
Also, remember to cut away from yourself.
6. Spread the flaps of the body wall apart and pin them down. Cut the umbilical
vein which extends through the liver.
7. Once the vein is cut, carefully pull the flap of skin, including the end of the
umbilical cord between the hind legs. Your are now able to see the organs
of the abdominal cavity.
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8. Identify at least 10 major internal organs in your fetal pig for your teacher.
Your teacher will assist you in identifying these organs one group at a time,
Some easily observed organs include the following:
trachea
lungs
diaphragm
ureter
fallopian tube
stomach
liver
small intestine
rib cage
testes
heart
thymus gland
kidney
pancreas
uterus
spleen
gall bladder
colon
ovaries
Note: If any organs of the pig are removed without permission of the
teacher, you will automatically lose 25 points on this lab report.
Dissection Lab Report
1. Label the respiratory diagram that follows.
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2. State the function of each of the respiratory structures in the chart below.
Structure
Function
diaphragm
larynx
bronchi
alveoli
3. Label the heart diagram that follows.
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4. State the function of each of the circulatory structures in the chart below.
Structure
Function
aorta
ductus arterious
inferior vena cava
left atrium
left ventricle
pulmonary veins
pulmonary artery
right atrium
right ventricle
5.
The ductus arteriosus is not found in the circulatory system of a pig after it is born,
Explain why this structure has to close after the pig is born,
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6. Label the digestion diagram on the next page.
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7. Complete the table which follows. State at least one function for the listing of
organs below. Indicate the system the organ belongs to (transport, endocrine,
excretory, nervous, digestive, etc.) The first structure is completed for you as an example.
Organ
Function
Organ System
brain medulla
controls involuntary activities like breathing
nervous
brain cerebrum
brain cerebellum
heart
lungs
thymus gland
immune
coronary arteries
respiratory
diaphragm
stomach
liver
gall bladder
small intestine
esophagus
large intestine
kidneys
ureters
spleen
pancreas
testes/ovaries
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FOR ONE OR TWO STUDENTS NOT PARTICIPATING IN THE DISSECTION!
You have been hired by an advertising agency to develop and present an informational
presentation. This presentation must be on either a poster or similar format that can be
displayed. The content of your informational presentation has been requested to deal
with one of the human body systems. The advertising agency would like you to include
the following items into your presentation. Because your presentation must be viewed by
clients, all writing or printing must be typed and spellchecked. No credit will be
awarded if this is not done.
Key points to be included into the presentation:
Typing and spellcheck (required)
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The organ system's purpose (10%)
At least six main components that make up this system and their role or function
(35%)
The relationship of this system to at least three body systems. (15%)
At least three medical problems with symptoms and preventions/treatments that
can be associated with this body system. (15 %)
Creation of at least two body system visual aids which may include drawings or
computer graphics. (10%)
Create a limerick about the chosen body system. This should be humorous and
thought provoking. (15%)
Note: Your presentation must be in your own words. You may not cut and paste
information. If I can google any phrase or sentence in your presentation, it will receive a
grade of ZERO.
Your tour may include a visit to any of the following systems. If another student is
doing a system tour before you, it will be required that you choose another system
however. You may work with one other student.
(1) Digestive
(2) Respiratory
(3) Nervous
(4) Excretory
(5) Circulatory
(6) Reproductive
(7) Endocrine
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