Cardiovascular System: The Heart

Purpose

Explain why you did this exercise. Where there any safety precautions you needed to follow? If so, what were they?

The safety precautions in this exercise were to wear goggles and gloves due to being exposed to chemicals and dissection of the sheep and cat heart. Appropriate work space was also required.

Exercise 1: Microscopic Anatomy of Cardiac Muscle Observations

Sketch and label your slide in the space provided. Include a description of the structures you observed on the slide.

See attached picture labeled cardiac muscle

Questions

A. What are …show more content…

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D. Compare the left and right sides of the dissected heart. What differences do you see?

The wall of the right ventricle is relatively thin. When it contracts, the right ventricle acts like a bellows, squeezing the blood against the thick wall of the left ventricle. The left ventricle uses six to seven times as much force to exert blood around the systemic circuit as around the pulmonary circuit. The left ventricle has an extremely thick muscular wall and is round in cross section

E. Compare and contrast the functions of the atria and the ventricles.

The atriums are smaller than the ventricles, have thinner muscle tissue, only have to pump blood to the ventricles.
The ventricles are larger in size, have larger muscle tissue and have to pump blood to either the lungs or around to the rest of the body.

F. List and describe the functions of the three layers of the heart wall Pericardium is the sac that holds the heart and blood vessels outside of the heart and includes a thin layer called the epicardium (Visceral layer of serous pericardium). The pericardium protects the heart and holds it in place. It also keeps the heart lubricated, so it can pump efficiently and smoothly, without it or the different layers of the pericardial sac catching on one another. Additionally, it limits the amount of space that the heart has to expand