Reasons to Use the Dissection Video and Accompanying PowerPoint Presentation
Reduce the number of specimens used by a class Increase the quality of the dissection for the students Review opportunity, increasing the learning experience
for the students Student unable to dissect due to pregnancy or
hypersensitivity to the preservatives Student chooses not to dissect due to ethical/moral
reasons
Dissection 101:
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Dissection 101:
As an educator you are responsible for the implementation of the dissection activity described in the video and
PowerPoint. You must have safety procedures and rules established for your classroom and make sure all of the students follow the rules to ensure a safe environment.
South Dakota Public Broadcasting and Dakota State University cannot in any way be responsible or liable for
any injury as a result of performing the described dissection. Complete the dissection if you feel it is
appropriate and safe for your individual class. Have fun and stay safe!
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Safety Considerations
Age appropriate activity for the children in your care Material Safety Data Sheet (MSDS) available for accident
reference Poison control number/phone readily available Latex free gloves, eye protection and apron/lab coat Eyewash station, shower and sink Sharp instruments (cut away from self and others) Sharps and specimen(s) disposal Encourage students to report all accidents Basic science laboratory rules (strictly enforced)
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Dissection 101:
Clam
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Dissection 101:
Clam
Exterior of the Clam Umbo (location):
Shell originates from here (oldest
section of the shell)
Dorsal(hinge side)
Anterior(closer to umbo)
Posterior(greater distance
from umbo)
Ventral(foot side - movement)
Shell produced by mantel in a series of rings, similar to the
rings of a tree – does not indicate age
Wood inserted during preserving process to keep the clam open
for dissection
Orientation
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Exterior of the Clam
Umbo
Hinge
Bivalve (2 shells)
Dorsal (top view)
Dissection 101:
ClamCut both adductor muscles on either
side of the hinge; do not cut through the middle of the clam
(dorsal side: posterior and anterior)
Always cut away from your hands and fingers
Slowly open the clam; continue to cut the adductor muscles if there is resistance.
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Dissection 101:
Clam
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Many times one of the mantles will rip when the clam is
pulled apart.
This is not part of the clam. It is an
extra piece of wood accidentally left in
the clam during preserving process.
Identify the following Structures
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Adductor muscles (2) relaxed – clam opens
contracted – clam closes
Identify the following Structures
MantleProduces shell and
provides protective andlubricated surface for the body structures
(torn)
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Pallial lineLocation on shell
where mantle attaches
Nacre/Mother of pearl Iridescent layer of the shell, pearls form here
Identify the following Structures
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Labial pulps (4)Two on each side of the mouth, used to sort food and move it toward
the mouth
Muscular FootUsed for movement, appears shrunken in
preserved clam
Gills (respiratory) Used to remove oxygen
from the waterMantleProduces the shell
MantleProduces the shell
Identify the following Structures
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Gills have feather- like appearance,
usually two on each side
Foot
Visceral mass Thick area above
foot, digestive glands, intestines and gonads
located here
MantleVisceral mass
Foot
Top View
Identify the following Structures
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Gills, mantle and labial pulps removed
Visceral mass with outer layer removed
Digestive glands (usually green)
produces enzymes to digest food
Gonads (usually yellowish/white) reproductive function
Tube-like intestines wind through the visceral mass
Identify the following Structures
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Gills, mantle, outer covering of visceral mass and labial pulps removed
Heart (exposed by removing protective membrane)
Each specimen may appear a little different, damagedadductor muscle
shown here (could indicate some type of disease or condition
that attacked the muscle)
Dissection 101:
Clam
Produced by Dakota State University and South Dakota Public Broadcasting
