Group members: _________________________________________
Period: ___________
Heart Dissection Procedure
Preparing your specimen: (If tools are in tray on a paper towel, discard towel before beginning.)
1. Using the scissors provided, cut the packaging away from the heart being careful not the
cut the heart itself.
2. Place the heart in the dissecting tray. Ensure it is oriented with the apex pointing
towards you, the base pointing away and that the right atrium/ventricle is on the left
side of the tray.
3. Confirm the right ventricle is on the left side of the tray by gently squeezing the
chambers on each side of the heart. The right ventricle has thinner walls and will
compress more easily.
4. Using paper towel, dry the heart. Discard used paper towel in the trash.
5. Place a metal probe, scissors, and scalpel next to the dissecting tray in preparation for
the dissection.
6. Before moving on to the next section, Ms. Safaee needs to confirm your heart
orientation and that you are prepared to dissect.
Ms. Safaee’s initials: ___________________
Dissection of specimen:
7. Cut through the wall of the right atrium and remove a portion of a wall. Your cutting
should provide an opening that allows a view of the right atrium. DO NOT cut through
the atrium or into the ventricle.
8. Identify the tricuspid valve. Use a metal probe to push through the opening of the valve
into the right ventricle.
9. Observe the number of flaps (cusps) that make up this valve.
Draw a picture of the right atrium and the tricuspid valve that you see on your lab sheet below:
10. Make an incision into the right ventricle and remove a portion of the wall similar to as
instructed for the right atrium.
11. Notice the difference in size of the right atrium and the right ventricle.
Draw a picture of the right side of your heart now that the atrium and ventricle have been
dissected.
12. Locate the aorta. Cut from the tip of the aorta through the wall down to the aortic valve.
13. Locate the pulmonary trunk on the pulmonary artery. Cut through the wall of this vessel
until you reach the pulmonary valve.
14. Observe the difference in diameter of these two vessels.
Which vessel is larger? ____________________________________________________
15. Cut through the wall of the left atrium so that you can view the bicuspid/mitral valve.
Observe the number of cusps that make up this valve.
How many cusps make up the bicuspid/mitral valve? ___________________________
16. Make an incision through the left ventricle below the interventricular groove (see image
below. The red line is the groove:
17. Observe the size of the left ventricle in relation to the right ventricle. Note your
observations below:
Ventricle comparison observations:
18. Using a metal probe, trace the pathway of blood from the left ventricle through the
aortic valve to the aorta. Do the same with the pathway from the right ventricle through
the pulmonary valve and out the pulmonary artery.
When finished, show this tracing to Ms. Safaee.
Ms. Safaee initials: _________________________
19. In the box below, write final observations on the structures of the heart we were able to
observe today and then proceed to clean-up.
Clean-up Procedure:
20. Dispose of the heart and any cuttings of heart tissue in the trash.
21. Using a paper towel, wipe dissection tray mat to remove any small pieces of tissue.
22. CAREFULLY rinse off any used tools in the sink (ENSURE you do not get pieces of heart
tissue in the sink).
23. Carefully dry your tools.
24. Place a piece of paper towel in the dissection tray and place your cleaned tools on top.
25. Wipe down the lab table and wash your hands.