Download B212Lab8 Friday

Bio212
Laboratory 8
Cat Dissection I
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Lab Schedule for Rest of Semester
• Cat dissection labs
– Dissection 1(today)
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Preparing the cat
Cardiovascular (Lab Exercise 45 in Hole)
Digestive (Ex. 48 in Hole)
Respiratory (Ex. 51 in Hole)
– Dissection 2 (next lab)
• Cat Urinary and Human/Cat Reproductive (Ex. 50, 51,
56, and 59 in Hole)
– Lab Exam 2 (5/7)
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Objectives for Today’s Lab
• Begin dissecting the preserved cat
• Begin to identify the structures listed on the Cat
Dissection Checklist in your Laboratory Guide
– Cardiovascular system
– Digestive system
• DON’T RUSH YOUR DISSECTION!!!
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Precautions
• You must wear lab coat, gloves, and goggles for
this lab!
• ABSOLUTELY NO FOOD OR DRINK
• Be EXTREMELY careful when using the scalpels
– Keep your index finger on the top of the blade
– Be careful not to inadvertently cut structures
• Use a blunt probe, or your gloved fingers to dissect
away tissue. Use the scalpel ONLY for initial
cutting. Proceed S-L-O-W-L-Y.
• Discard scraps/liquid into the appropriate container
• Gloves, paper towels, plastic bags -> regular trash
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Getting started…
• Work in groups of three (there are ? cats)
• You may have either a male or female cat (there
should be three of each); note which you have
• Get some paper towels and keep them at your lab
table
• Get a lab coat; when finished, put back in box
• Get your instruments and dissecting tray (large trays
in the front of the lab) ready
• Get a cat and cut open the sealed bag and discard
the fluid into the “Liquid Waste”
• Let the cat out of the bag! 
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Getting started…
• We are going to begin dissection a little
differently than stated in Hole’s Lab Manual
– We will be making a ventral incision rather than a
dorsal incision (see you Laboratory Guide)
• See the Introduction to the Cat in your Lab
Guide, and follow the instructions carefully
– This will prepare the cat for the rest of the
dissections
– Disregard any instructions to remove the skin
• Look at the preserved, dissected cat to get an
idea of what you’ll see for each system
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Getting started…
• Once the initial cuts have been made according
to the instructions in the handout, you are ready
to continue
• Use Hole’s Lab Manual, Exercise 55, and
follow the instructions there to examine the
cardiovascular system
• Note that the cats have been dual injected with
dyes (red = arteries, blue = veins)
• Note the differences in the anatomy of the cat
(vs. the human) in the blood vessels around the
heart and in the pelvic area (see your
Laboratory Guide)
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General Dissection
• Use the handout as a guide to where to make
incisions
• You can cut through the skin and muscle (I will
not ask you muscles on the lab exam)
• After folding back skin and muscles:
– LOOK!!! Note the placement of organs and
structures
– Once you have gotten and idea about how the
organs and structures are placed in the body, THEN
continue…
• Note the position and structures surrounding the
diaphragm before going on to the next step
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Cardiovascular system
• Open the rib cage by cutting just to one side of
the sternum with scissors then spread the ribs
• Examine the position of the thoracic organs, i.e.,
heart and lungs and the membranes surrounding
them
• Gently begin to remove the fatty/glandular
tissue from the surface of the heart to expose the
vessels around the heart (see preserved cat)
• Work S-L-O-W-L-Y to dissect away the CT
from the vessels. Use a blunt probe.
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Cardiovascular System Dissection
• You should be able to locate the vessels listed
in your Lab Guide (Cat Dissection Checklist)
• You should make a frontal (coronal) section
through the heart to expose the chambers
• You should be able to recognize/name the
chambers of the heart
• Notice the pulmonary vessels and try to trace
their path to their connections to the lungs
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Cardiovascular System
• In order to see the vessels that you are
responsible for on Cat Dissection Checklist,
you will need to
– Begin at the heart and work outwards taking care
not to destroy any organs we will be examining in
the next labs
– Look at the vessels in the neck
– Look at the vessels in the thorax and abdomen
– Look at the vessels in the legs down the first third
of the femur
• Use the atlases I have placed in the front of the
room if you need help in identifying
structures/organs
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Digestive System
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EVERYONE should do the following dissections:
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EVERYONE should locate the following:
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gastroesophageal junction and longitudinal section of the stomach
parotid gland
ileocecal valve (sphincter)
esophagus
stomach (after examining it in situ, you should make a longitudinal cut
along the greater curvature and look at the interior)
duodenum
pancreas
remainder of small intestine
mesenteries of the small intestine
large intestine (you need not locate the most distal portion of the large
intestine (rectum, anal canal) or the anus until we do the
urinary/reproductive systems
Special dissection: hepatobiliary system (if you dare! )
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Respiratory System
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EVERYONE should do the following dissections:
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Locate the root of the lung where blood vessels and bronchi enter/exit
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Dissect the larynx
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Make a cut SUPERIOR to the thyroid cartilage
Lift up the larynx and trachea to visualize the structures of the intact larynx
THEN, make a longitudinal cut through the larynx to visualize the structure inside
Remove one lung and make a coronal section through it, observing the
internal structure
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When You Are Done for the Day…
• Put any removed organs back in the cat
• Wrap flaps of skin and muscle around the cat to
keep it moist, and spray it with Ward’s Safe
Preservative that is on the table in the front of
the lab (WSP)
• Wrap the cat with paper towels and spray the
paper towels with WSP until soaked
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When You Are Done For the Day
• Place the cat into a new plastic bag, remove as
much air as you can, and seal it tightly with the
bag sealer.
• Then put it in another bag and seal it tightly
with the bag sealer. When you are done,
PLEASE SHOW ME!!!
• Tag your bag with the names of the people in
your group and write “Dr. Erianne” in pencil
on tag
• Place the bag in the white plastic tray
• Wash all instruments THOROUGHLY and
replace them in tray.
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