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

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)

Click Dissection 101: Clam

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

Click Exterior of the Clam Umbo Hinge Bivalve (2 shells) Dorsal (top view)

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

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.

Identify the following Structures Click Adductor muscles (2) relaxed – clam opens contracted – clam closes

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

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

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

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

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

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

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)

Dissection 101: Clam Produced by Dakota State University and South Dakota Public Broadcasting