This video is a detailed and fairly graphic account of the dissection of a pig’s heart. The dissection, and accompanying commentary, shows all of the main features of the heart. It should be shown after students have been made aware of the heart structure.
Dissection is a sensitive issue. It is worth telling students about the video and any dissection the lesson before it is due to take place. In that way, students with real concerns can talk to you and alternative self-study away from the laboratory can be organised if necessary.
Reassure students that the heart is from a pig and that the animal was not killed for the purpose of the dissection but would have been killed for food production.
The first few minutes of the video clip show the heart connected to a set of lungs. This is good to see but looks quite bloody. You may want to preview this section to see that it is suitable for your students. If in doubt, advance the video to 54seconds where the heart is cleaned up and the anatomy is being described.
The video can be the prelude for an actual dissection of a hearts obtained from the butchers. Take care to be sensitive to cultural objections to using materials from pigs or cows. Discussing this with students prior to the lesson is recommended. In certain circumstances you may want to inform parents in advance of the class. It is worth, have an alternative activity prepared for students who do not wish to take part or watch a dissection.
Remember to consider the sensible precautions for using scissors or scalpels and it is advisable to use cutting boards. Supplying students with disposable gloves can encourage them to use fingers, or glass rods, to explore heart chambers and blood vessels.
Challenge students to find the different chambers and major blood vessels (often the atria are missing as they have been chopped off during butchery of the carcass).
It is worth showing students the coronary arteries that supply the cardiac muscle. Show how small they are and note that these are the vessels that, if blocked, cause a heart attack. Remind students of the link between excess fat in the diet and blocked arteries causing a heart attack.