This document is not meant to be a substitute for a formal laboratory report. The Lab Report Assistant is simply a summary of the experiment’s questions, diagrams if needed, and data tables that should be addressed in a formal lab report. The intent is to facilitate students’ writing of lab reports by providing this information in an editable file which can be sent to an instructor. Purpose Explain why you did this exercise. Where there any safety precautions you needed to follow? If so, what were they?
The purpose of this exercise is to learn the anatomy and over all composition of how the heart works and the blood flows through the four chambers of the heart. Always follow the Labpaqs MSDS: Material Safety Data Sheet and do all dissection / use in well-ventilated area. 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. cardiac muscle cardiac muscle Questions A. What are some unique structural features of cardiac muscle?
The cardiac muscle is essentially limited to the heart. As far as the structural features include a striated appearance that allows for strong muscle contractions, but it also differs from skeletal muscle. Although the cells are much shorter, so they are called myocytes rather than fibers. Cardiac muscle is considered involuntary because it is not usually under conscious control; it contracts even if all nerve connections to it are severed. Cardiac muscle’s role is to pump blood oxygenated blood containing nutrients to body tissues and deoxygenated blood to the lungs to receive oxygen.
B. What are intercalated discs and what do they do? Present in cardiac muscle are intercalated discs, which are connections between two adjacent cardiac cells. The intercalated discs functions are to support synchronized contraction of cardiac tissue. C. Why does cardiac muscle have to be both elastic and strong? Cardiac muscles and smooth muscles are called involuntarily controlled muscles; the cardiac muscle is strong and elastic so it can pump adapted for carrying high-pressure blood. D. Which of the three layers of the heart did the tissue used to make your slide originate from?
Cardiac muscles consist of the heart is surrounded by a fluid filled sac called the pericardium, then there are divided into three layers the epicardium (outer protective layer of the heart), myocardium (muscular middle layer wall of the heart), and endocardium (inner layer of the heart that is continuous with the inner lining of blood vessels). Our slide was made from the myocardium. Exercise 2: The Pulmonary and Systemic Circuits Questions A. Trace the flow of blood through the pulmonary and systemic circuits. Begin in the right atrium and end in the superior/inferior vena cava.
Be sure to list every vessel, heart chamber, and heart valve the blood flows through. Blood passes through the pulmonary and systemic circuits from the body, which gets returned to the heart through the superior vena cava where it enters the first of four chambers of the heart in the right atrium first. It then would pass through the tricuspid valve and into the right ventricle. From there it would pass through the pulmonary valve and go through the pulmonary arteries and into the lower lobes of the lungs. The lungs will then oxygenate the blood and it returns to the heart through the pulmonary veins, where this blood flow enters the heart chamber called the left atrium.
It then travels through the mitral valve and into the left ventricle. As the heart pumps, the blood then exits the heart through the aortic valve, and goes out the aorta where the blood is then carried to the brain and other vital organs of the body and tissue. B. Explain what you learned from the online human heart dissection. I learned on the online human heart dissection how the heart blood flows works, the anatomy, the four valves, four chambers both left and right (two atriums and two ventricles) structures operate, muscle structures, ridges of the ventricles and septum, and the lungs work together for blood flow.
Exercise3:SheepHeartDissection/CatHeart Dissection and Comparison Questions A. Compare the structure of the fetal pig heart and sheep heart. How are they similar? How are they different? They both share the same anatomic structures, seeing as it is a characteristic of mammals to have four chambered hearts. The main difference is that the sheep heart is bigger than the fetal pig’s.