Transcript of Reasons to Use the Dissection Video and Accompanying PowerPoint Presentation Reduce the number of...
- Slide 1
- 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: Click
- Slide 2
- 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! Click 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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- Click Dissection 101: Clam
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- Click Dissection 101: ClamExterior 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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- Click Exterior of the Clam Umbo Hinge Bivalve (2 shells) Dorsal
(top view)
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- Dissection 101: Clam Cut 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 Cut Slowly open the clam; continue to cut the adductor
muscles if there is resistance. Click Student Cuts: YouTube
SDPB
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- Dissection 101: Clam Click 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.
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- Identify the following Structures Click Adductor muscles (2)
relaxed clam opens contracted clam closes
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- Identify the following Structures Mantle Produces shell and
provides protective and lubricated surface for the body structures
(torn) Click Pallial line Location on shell where mantle attaches
Nacre/Mother of pearl Iridescent layer of the shell, pearls form
here
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- Identify the following Structures Click Labial palps (4) Two on
each side of the mouth, used to sort food and move it toward the
mouth Muscular Foot Used for movement, appears shrunken in
preserved clam Gills (respiratory) Used to remove oxygen from the
water Mantle Produces the shell Mantle Produces the shell Remove
the upper mantle and labial palps to expose gills and visceral mass
Cut Lay your scissors/scalpel flat; lift the upper mantel and
labial palps with a forceps; slowly/carefully remove these
structures Mantle Labial palps
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- Identify the following Structures Click Gills have feather-
like appearance, usually two on each side Foot Visceral mass Thick
area above foot, digestive glands, intestines and gonads located
here Mantle Visceral mass Foot Top View
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- Identify the following Structures Remove the gills and outer
layer of the visceral mass Cut #1: Lay your scissors/scalpel flat;
lift the gills with a forceps; slowly/carefully remove the gills
Click Cut #1 Cut #2 Cut #2: Lay your scissors/scalpel flat and
remove the outer layer of the visceral mass, circular shape cut
Student Cuts: YouTube SDPB
- Slide 13
- Identify the following Structures Click Gills, mantle and l
abial palps 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
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- Identify the following Structures Click Remove the membrane to
expose the heart Use a forceps & scalpel/scissors to remove the
membrane Heart Student Cuts: YouTube SDPB
- Slide 15
- Identify the following Structures Click Gills, mantle, outer
covering of visceral mass and l abial palps removed Heart (exposed
by removing protective membrane) Each specimen may appear a little
different, damaged adductor muscle shown here (could indicate some
type of disease or condition that attacked the muscle)
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- Dissection 101: Clam Produced by Dakota State University and
South Dakota Public Broadcasting