Heart Dissection

You will be exploring the heart, making observations, taking pictures and labelling them during this dissection.  And posting all of this to your blog! POST IT BY WEDNESDAY!

External anatomy

Take pictures of both the front and back of the heart - label the following on each picture if applicable:

• left and right atria
• left and right ventricles
• aorta
• superior and inferior vena cava
• pulmonary trunk / arteries
• pulmonary veins
• septum
• coronary arteries and veins

Observations:  Write your observations about the heart's external anatomy - size, shape, colour, weight. What are the differences between the shape/size of the atria and ventricles?  Describe the aorta and/or pulmonary trunk.  Did you find any veins?  Describe them.

Internal Anatomy

Use the scissors to make the incisions into the chambers of the heart.  Starting with the right side, you are going to cut down the pulmonary trunk, continue cutting through the ventricle to the bottom.  Try and stay in the middle of the chamber, it will open like a hot dog bun.  Then find the AV valve (and attached chordae tendinae) and cut up into the right atrium.  Take pictures along the way!

You will do the same on the left side, starting from the left atrium cutting down into the left ventricle.

Take pictures so that you can label the following:

• inside of left and right ventricles
• inside of left and right atria
• AV valves (L & R)
• chordae tendinae
• aortic and pulmonary semi-lunar valves
• septum
• aorta
• pulmonary trunk
• any attached veins (pulmonary, superior vena cava, inferior vena cava

Observations:

Write about the thickness of the walls of the ventricles - compare R and L

Valves & chordae tendinae - what do they look like?  feel like?  

Inside of the atria and ventricles - any observations on size, shape, colour

Inside of blood vessels - any observations on size, shape, colour

Questions:

1. What was the most surprising thing about dissecting the heart?  Describe what your expectations were and if they were met.
2. Why are the atria and ventricles so different (compare their structure to their function)?
3. Why is the left ventricle more muscular than the right?
4. What are function of the heart valves?  Describe how the structure of the valves relates to their function (including chordae tendinae).
5. Use one of your pictures to trace the path of blood through the heart (add arrows?)