Download Lab 11

CHE106: C h e m i c a l
S c i e n c e
Autopsy
C o n c e p t s
1
Name
Partners
Date
Objectives

Perform a whole-body forensic dissection of a mammal

Identify the major anatomical features of the body in a
dissected specimen

Examine the relationship between structure and function in the
mammalian body
SAFETY AND HYGIENE
Do not place your hands near your mouth or eyes while handling
preserved specimens. Most preservatives in use today are nontoxic to the skin but they may cause minor skin irritations. If
the preservative gets on your skin, wash with soap and water. If
the preservative gets in your eyes, rinse them thoroughly with
the safety eyewash.
Wear lab gloves.
Lab gloves and paper towels go in the regular trash. Skin and
pieces of pig tissue and organs go into the biohazard bag.
After bagging your pig, rinse your tray.
with disinfectant. Wash your hands.
MATERIALS
Fetal pig (Sus scrofa)
Scissors
Gloves
Bone cutters
Forceps
Dissecting pans
String
Metric ruler
Triple beam balance
Weigh paper or weigh boats
Paper towels
Biohazard bag
Wipe up your station
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S c i e n c e
C o n c e p t s
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Note: The arteries of the pig have been injected with red latex
to facilitate identification of the vessels of the circulatory
system.
I. External Description and Preparation for Autopsy
1. Take the body from the body bag and place it on the
dissecting pan.
2. Record the following in the Data Sheet: age, length, weight,
sex, color, and color pattern of the skin. Record any evidence
of injury.
Female: find the urogenital papilla (urinary opening) and its
anatomical position with respect to the anus.
Male: find the urinary opening just below the umbilical cord and
its anatomical position with respect to the anus. Find the
scrotum, the sac that contains the testes.
Note: Both male and female exhibit rows of nipples.
3. Examine the anterior, posterior, dorsal, ventral, medial, and
lateral external structures on the pig.
a. The nares (nostrils) have a ___________________ position
on the pig
b. The tail has a ____________________ position on the pig
c. The umbilical cord has a _________________ position on
the pig
d. The ears (pinna) have a _______________ position on the
pig
4. Your instructor will demonstrate how to tie the specimen to
the dissecting tray so that it is secure.
II.
Internal Examination
A. The Thoracic (chest) Cavity
1. Obtain scissors and cut the pig as shown in the figure.
2. Use your fingers to probe the chest area. Feel the hard
sternum (breast bone)and ribcage. Move your fingers down until
CHE106: C h e m i c a l
S c i e n c e
C o n c e p t s
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you feel the bottom of the rib cage. This is where the thoracic
cavity ends (marked X in the figure).
3. Make an upside-down V incision starting a X (line 1). Cut
from X to the umbilical cord and around the cord (line 2)
4. Follow lines 3, 4, 5, 6, and 7. The thoracic and abdominal
cavities are now exposed.
.
5. Locate the following structures:

The larynx is used for sound production

The trachea is also known as the
windpipe

The lungs (right and left) consist of
lobes and are used to bring oxygen into
the body and to expel carbon dioxide)

The heart is muscular structure that pumps blood to and
from the lungs and rest of the body

The muscular diaphragm is the main muscle of breathing. It
separates the thoracic from the abdominal cavity.
6. Remove and weigh the heart and lungs (together) and enter the
data on the Data Sheet.
7. Answer the following:
a. In pigs and humans, the heart is located on which side
of the thoracic cavity (right or left)?
b. Which of the 3 structures (organs) you examined in the
thoracic cavity are part of the respiratory system?
c. Which structure (organ) is part of the cardiovascular
system?
CHE106: C h e m i c a l
S c i e n c e
C o n c e p t s
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B. The Abdominal Cavity
1. Locate the following structures in the abdominal cavity:

The liver is a large brown organ located just below
the ribs mainly on the right side

The stomach is located on the left, just below the
liver

The spleen is a thin, brown, organ lateral to the
stomach. It is part of the lymphatic system and has a
role in fighting disease and breaking down old red
blood cells

The small intestine is a large coiled tube in the
bottom half of the abdominal cavity. It is held in
place by connective tissue

The large intestine (colon)is shorter but has wider
coils than the small intestine. It is visible on the
back wall of the lower abdominal cavity

The kidneys are located in the posterior portion
(back) of the abdominal cavity. They are bean shaped

The urinary bladder is located in between the vessels
of the umbilical cord in the fetal pig

Gently lift the liver to see the small gallbladder in
the underside

The ovaries and uterus (female) are small. Consult
your instructor

If your pig is a male, check to see if the testes are
in the abdominal cavity or if they have descended into
their mature position in the scrotum
2. Remove and weigh some of these organs (consult the data
table) and enter the data in the Data Table.
.
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S c i e n c e
C o n c e p t s
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3. Test your knowledge
a. Identify 4 organs that are part of the digestive
system
b. Which organ makes urine? Which organ stores urine
until it is released?
c. One of the organs you examined makes bile, a fluid
used in digestion. Another, small organ, stores
bile. Identify these two organs
d. The most important organ in the digestive system is
the small intestine. This is where much of the
digestive process occurs and also where nutrients
are absorbed into the bloodstream. Which organ
processes the solid wastes that will be eliminated
from the body?
e. Which organ in the female produces eggs?
III. Optional Examination of the Nervous System
Make an incision as described on page 60 from ear to ear across
the top of the skull. Separate the scalp from the skull. Expose
the brain to observe.
V. Questions:
A. What is an autopsy?
B. List 4 possible causes of death
C. List 4 possible manners of death
D. Is an autopsy always required in homicide cases?
E. What are the qualifications of person who performs forensic
(medico-legal)?
CHE106: C h e m i c a l
S c i e n c e
C o n c e p t s
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F. Why does the process of forensic autopsy begin at the crime
scene?
G. Describe the process of moving a body from a crime scene to
the morgue
CHE106: C h e m i c a l
S c i e n c e
C o n c e p t s
DATA SHEET
AUTOPSY REPORT
Name of Examiner __________________________
Date of Examination __________________________
I. External Description
Length (cm)
Weight (grams)
Sex
Color and pattern
Scars, tattoos, or moles
Evidence of injury
(describe)
II. Internal Examination
Heart and Lungs (grams)
Stomach (grams)
Liver (grams)
Kidney (1) (grams)
III. Cause and manner of death (if human)
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CHE106: C h e m i c a l
S c i e n c e
C o n c e p t s
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Instructor
Handouts: Instructions, figure of incisions, Data sheet
Introduction
The pigs are preserved in formaldehyde, wear gloves. They were
taken from pregnant sows that were being processed for food.
(the cause of death is suffocation, because when the placenta is
removed, the fetus has no oxygen, the manner of death is
slaughter, which is the term we use for killing animals. If a
person, this would be homicide)
Autopsy is an examination of a body after death. The forensic
autopsy attempts to determine the cause of death and the manner
of death (the instrument or illness). There are 4 possible for
humans – natural, accidental, suicide, homicide
The forensic autopsy is conducted by a pathologist, coroner, or
chief medical examiner. You need an MD and certification in
pathology. Hospital autopsies are different (natural cause is
assumed). There is a very specific procedure used which you will
read about later.
An autopsy report is always included and you have a data sheet
that will form the report
You first begin with an external description of the body. record
the clothing, age, sex, race, height, weight, scars, tattoos,
moles, anything and everything. Also injuries or wounds and
evidence of past injury.
Also include degree of rigor mortis or putrefaction
The body is moved carefully from the crime scene to the morgue
where it is washed for better viewing and then the autopsy
performed.
Then, incisions are made and the internal structures examined.
We will look at organs in the thoracic cavity (chest) and
abdominal cavity. The structures are from the respiratory,
cardiovascular, digestive, urinary, reproductive, lymphatic
systems
A forensic pathologist might also make some microscopic slides
and send tissue for toxicology and take samples of blood and
urine for drug or poison analysis.
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S c i e n c e
C o n c e p t s
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The ME presents the findings in a data sheet and includes an
opinion on the cause and manner of death. It is a factual report
and includes only evidence that can be substantiated
There are some terms to know before beginning the autopsy.
Anterior = towards the front
Ventral = belly side
Dorsal = back side
Posterior = towards the back
Medial = towards the midline
Lateral = towards the sides
Superficial = towards the surface
Deep = away from the surface
External = outer
Internal = inner