Read Me. covering the Heart Anatomy. Labs. textbook. use. car: you

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1 Heart Anatomy Lab Pre-Lab Exercises Read Me These exercises should be done before coming to lab, after watching the videos covering the Heart Anatomy Labs. Answer the questions in this guide using the information given in the online videos. Use imagess in your text for help. If you are not able to answer a question or label a structure, MAKE A NOTE OF IT and try again after lab. We will be having you label images while reading descriptionss of heart anatomy. As you read a description, label the bold-faced terms on the accompanying image. The following refers to "red vessels" and "blue vessels" ". If the images are in black and white, use colored images in your textbook. Here is an example of how to do this, using the description of a car: Student reads the following: The basic car: most cars have doors, a trunk, and wheels with tires. However, many cars have 2 setss of doors: one for the front seats (called the front door), and another for the back seats (called the rear door). These are 4-door sedans (label 4-door sedan ). Student labels the image using the letters in the above paragraph: Where will you get the info to label correctly? The videos and your textbook.

2 NOTE: The text and images are modified from Benson ett al: Anatomy & Physiology Laboratory Textbook, 8/e Completee Version The accompanying images reveal two external views of the heart; anterior (label anterior ) and posterior (label posterior ). Please remember we always refer to the patient s right side and left side, so the right atrium is on the left side of the image, etc. Label them in the spaces provides marked "patient's " and "patient's ". Red colored vessels in your textbook images, like the one below (label 2 vessels oxy below) carry oxygenated blood and blue ones carry deoxygenated blood (label 2 vesselss deoxy below). Views: Patient's side Patient's side Patient's side Patient's side

3 Internal Anatomy Label the image on the next page using the bold-faced terms The study of the external anatomy of the heart is relatively simple once the internal anatomy is understood. The accompanying figure reveals the internal anatomy of the human heart. Chambers of the Heart Image on next page Note that the heart has four chambers: two small upper atria and two larger ventricles. The atria receive all the blood that enters the heart and the ventricles pump it out. Note that the right atrium in the frontal section is on the left side of the illustration and the left atrium is on the right. Observe, also, that although the right ventricle is somewhat larger than the left ventricle, the left ventricle has a thicker wall. Separating the two ventricles is a partition, the ventricular septum. Tissues the Heart Image on next page The wall of the heart consists of three layers: the myocardium, the endocardium, and the epicardium. The myocardium is the muscular portion of the wall that is composed of cardiac muscle tissue. Note in the enlarged section of the wall that the myocardium makes up the bulk of the wall thickness. Lining the inner surface of the heart is the endocardium. It is a thin serous membrane that is continuous with the endothelial lining of the arteries and veins. An infection of this membrane is called endocarditis. Attached to the outer surface of the heart is another serous membrane, the epicardium, or visceral pericardium. The production of serous fluid by this membrane on the outer surface of the heart enables the heart to move freely within the pericardial sac. Note that the pericardial sac, or parietal pericardium, cannot been seen in this image. Draw where you think it would be with a dotted line (hint...it surrounds the heart, but doesn't cover the big vessels on top).

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5 Valves of the Heart The heart has two atrioventricular and two semilunar valves. Between the right atrium and the right ventricle is the tricuspid valve. Between the left atrium and the left ventriclee is the bicuspid, or mitral valve. Observe, also, thatt the edges of the cusps have fine cords, the chordae tendineae, which are anchored to papillary muscles on the wall of the heart (see frontal section image). These cords and muscles prevent the cusps from being forced up into the atria during systole (ventricular contraction). The other two valves are the pulmonic semilunar and aortic semilunar valves. They are located at the bases of the pulmonary trunk and the aorta. They preve ent blood in those vessels from flowing back into the heart during diastole (relaxation phase). Note in the superior sectional view that each of these valves has three small cusps.

6 External Anatomy Please label all bold-faced terms on both images if possible As mentioned, the study of the external anatomy of the heart is relatively simple once the internal anatomy is under stood. The accompanying image reveals two external views of the heart: Anterior view and Posterior view. Label all terms on both images! Anteriorr View In order to see the structures, we have removed the pericardium. Note that the heart lies within the mediastinum at a slight tilt to the left so that the apex, or t ip of the heart, is somewhat on the left side. The base of the heart is at the top, where all the blood vessels are entering and leaving the heart. Differentiating the right ventricle from the left ventricle is best done by locating the interventricular sulcus first. The yellow material seenn in the sulcus consists of fat deposits. The left ventricle is on the left side of the interventricular sulcus, and the right ventricle is to the right of it. You can use the interventricular sulcus and the atrioventricular sulcus to distinguish the right atrium, left atrium, right ventricle, and the left ventricle. Both atria have large flaps of tissue surrounding them; these are the right and left auricles. Posterior View Of course, on the posterior aspect, all of these same structures are on the opposite side of the image. LABEL THE atria and ventricles, as well as the base and apex on the posterior image, remembering that it is not in correct anatomical position! Views:

7 Vessels of the Heart - Please label all bold-faced terms Anteriorr Aspect The major vessels of the heart are the two venae cavae, the pulmonary trunk, the four pulmonary veins, and the aorta. Three portions of the aorta are on the anterior aspect: : a short ascending aorta that emerges from the left ventricle, a curving aortic arch, and a portion of the descending aorta that passes down through the mediastinum behind the heart. The superior vena cava is the upper blue vessel on the right atrium; it conveys deoxygenated blood to the right atrium from the head and arms. The inferior vena cava is the lower blue vessel that empties deoxygenated blood from the trunk and legs into thee right atrium. From the right atrium, blood passes to the right ventricle, wheree it leaves the heart through the pulmonary trunk. This large vessel branches into the right and left pulmonary arteries, which carry blood to the lungs. Also, identify the ligamentum arteriosum. Blood is drained from the lungs by means of the four pulmonary veins (four small red vesselss in a colored image), which carry it to the left atrium. From the left atrium the blood passes into the left ventricle, wheree it exits the heart through the aorta. There are several vessels that feed the myocardium itself. The coronary vessels in the atrioventricular sulcus are the right coronary artery and the small cardiac vein. The interventricular sulcus is the slight depression over the ventricular septum that contains the anterior interventricular artery and the great cardiacc vein. Wrapping around to the back of the heart, you can see just a little off the circumflex artery before it disappears to the back.

8 Posterior Aspect The posterior view of the heart reveals more clearly the position of the four pulmonary veins and additional coronary vessels. The two right pulmonary veins are seen near the superior vena cava. The two left pulmonary veins are situated to the left off the right pulmonary veins. The appearance of a single vessel lying below the aorta is actually the site of the division of the pulmonary trunk into the right and left pulmonary arteries. The following coronary arteries are seen on this side of the heart: the circumflex artery, wrapping around from the front, the right coronary artery, which is also wrapping around from the front on the right side in the right atrioventricular sulcus, and the posterior interventricular artery. The major coronary veins on this side are the middle cardiac vein,, which parallels the posteriorr interventricular artery, and the posterior interventricular vein, which lies in the interventricular sulcus with the similarly named artery. All these coronary veins empty into the large coronary sinus, which lies in the atrioventricular sinus.