Sheep Heart Dissection Video

Sheep Heart Dissection

Q1: What is the purpose of the pericardium?

The pericardium is the sac that holds the heart in place. There is mucous on the walls of the pericardium so that if the heart is jostled around, there is no friction.

Q2: Observe the blood vessels connecting to the heart. How do arteries differ from veins in their structure?

The walls of arteries are thicker than those of veins (due to the higher pressure in arteries), and arteries always go away from the heart.

Q3: Place your finger inside the auricle. What function do you think the auricle serves?

Auricles collect oxygenated blood from lungs and deoxygenated blood from the bloodstream.

Q4: Observe the external structures of the atria and ventricles. What differences do you observe?

The walls of the ventricles are thicker than those of the atria. Blood also flows into the right atrium, into the right ventricle, into the left atrium, and into the left ventricle.

Q5: Find the following structures. Use pictures or words to describe each.
             a) Exit from the coronary sinus
             b) Exit from the inferior vena cava
             c) Right Atrioventricular Valve (Tricuspid Valve)

             a) Blood exits from the coronary sinus into the right atrium.
             b) Deoxygenated blood enters the heart through the inferior vena cava, and continues on to the right atrium.
             c) The tricuspid valve stops blood in the right ventricle from back-flowing into the right atrium. 

Q6: Draw a picture of the tricuspid valve, including chordate tendinae and the papillary muscle.

Q7: Why is the "anchoring" of the heart valves by the chordate tendinae and the papillary muscle important to heart function?

They are there to prevent the tricuspid and bicuspid valves from collapsing into the atria when the heart contracts.

Q8: Using pictures and/ or words describe what you see.

The bicuspid and tricuspid valves prevent backflow of blood into the left atrium and right ventricle.

Q9: What is the function of the semi-lunar valves?

They prevent arterial blood from re-entering the heart. 

Q10: Valvular heart disease is when one of more heart valves does not work properly. Improperly functioning heart valves can lead to regurgitation, which is the backflow of blood through a leaky valve. Ultimately this can lead to congestive heart failure, a condition that can be life threatening.
             a) If this valve disease occurs on the right side of the heart, it results in swelling in the feet and ankles. Why might this happen?
             b) If the valve disease occurs on the left side of the heart, what complications would you expect to see?

             a) Blood is not properly flowing in through the inferior vena cava through the heart to get reoxygenated, so blood is staying in feet and ankles and causing swelling.
             b) Swelling of the lungs as blood is backflowing from the the left ventricle into the left atrium into the lungs. 

Q11: Using pictures and/ or words describe what you see.

Cordae tendinae connects papillary msucle to the bicuspid valve.

Q12: Describe how the left and right sides of the heart differ from each other.

The left side of the heart carries oxygenated blood, and the right side carries deoxygenated blood. The walls of the left side are thicker because it needs more power to push blood out to the body.

Q13: Draw and label all structures visible in the interior of the cross-section.

Unit 3 Reflection

sphygmoman 

sheep heart

This unit was about the cardiovascular system - circulation, the heart, the heartbeat, blood, blood vessels, diseases, and respiration. The cardiovascular system transports materials (oxygen,glucose), and removes waste materials (carbon dioxide, urea) from cells by a fluid-filled network of vessels that connect to heart, lungs, kidneys, intestines, and liver. Cardiovascular health is when a person maintains a healthy weight and diet, controls their blood pressure and cholesterol, prevents atherosclerosis and diabetes, and controls inflammation. Heart attacks and strokes can be caused by blockage of blood vessels in heart/ brain. To improve cardiovascular health, a person can exercise, not smoke, minimize stress, and smile/ laugh. I would like to learn more about bleeding out from arteries/ veins.

I am really interested in the heart, so this was a really great unit for me. Some memorization of the difference between blood vessels I struggled with, but the structure of the heart, heart attack/stroke, and the sheep heart dissection were really good and interesting for me.

chalk heart

Since I set my health goals for unit 2, I have been making an effort to get more sleep and relax more when I have a heavy workload or am struggling with something. Since I took this class because of my interest in anatomy and physiology (and my continued interest in it), for the rest of the semester, I am really focusing on fully understanding what we are learning.