Healthy Lung Lungs Diagram of a Smoker after Smoking Cancer Anatomy And Heart Drawing Images AFter Smoking Wee of a Weed Smoker

Healthy Lung Biography

(Source google.com)

The speed at which the heart contracts is determined by many different factors, including age, sex, eight, physical condition, and mental state. The two heart sound make one complete heart beat. The normal resting rate is 70-100 per minute. In a well-conditioned athlete, the rate may be considerably lower. Heart rate can be determined either by using a stethoscope and counting the number of complete cycles of heart beats per minute, or by taking the pulse. Each time the left ventricle pumps blood out into the body, the elastic arteries are stretched. This stretching can be felt as an expansion in the arteries near the surface of the body. The pulse rate is usually counted on the radial artery in the wrist. The artery can be felt on the ventral surface of the thumb side of the forearm, just proximal to the wrist. Use your fingertips when trying to find the pulse, not your thumb. If you use your thumb you will end up counting your own pulse on the artery in the thumb. You can also count pulse rate on the carotid artery on either side of the neck, but remember not to apply too much pressure! Click on the link to the right to determine your patient's heart rate. Did you count about 120 bpm? Although you have already examined the heart of your fetal pig, you will also study the sheep heart, since it is larger and many structures are easier to see. As you examine the heart you should keep in mind the pattern of blood flow through it. Remember that deoxygenated blood returning from the body enters the right atrium via the anterior vena cava and posterior vena cava.
From the right atrium blood passes into the right ventricle, and from there to the lungs via the pulmonary artery. After being oxygenated in the lungs, blood returns to the left atrium via the pulmonary veins. From the left atrium it enters the left ventricle, and is pumped out to the body via the aorta. Begin by observing an intact heart. The narrow, pointed end is the apex, or posterior end of the heart. Notice that the heart is very muscular in this area because the ventricles are located at this end of the heart. The wider end, from which the blood vessels arise and enter, is the base (not labeled), or anterior end. The image to the right shows the ventral surface of the heart. It can be identified by the prominent groove, the interventricular sulcus. This groove marks the division between the left ventricle (on your right as you look at the ventral surface and the right ventricle (on your left as you look at the ventral surface). Two large vessels spring from the base of the heart on the ventral surface. These large vessels are the aorta (not visible in this image) and the pulmonary artery. The pulmonary artery leaves the heart slightly to the left of and ventral to the aorta. To the right of the two large arteries locate the thin-walled left atrium. To the left of these arteries locate the right atrium. Each atrium bears a thin-walled flap or appendage, the auricle. Next examine the dorsal surface of the heart. Again, the ventricles occupy the apex of the heart. On the right side of the dorsal surface (as you look at the heart) at the base of the heart is the right atrium. Locate the large thin-walled anterior vena cava and posterior vena cava, just to the left of the right atrium. The anterior vena cava returns blood from the anterior part of the body, and the posterior vena cava from the posterior part of the body. Though not clearly visible here, note that on the left side of the heart two pulmonary veins enter the left atrium. Now examine a heart which has been cut open. Orient yourself as described above and locate the cut which has opened the right atrium and ventricle. Remember that the ventricle is the thicker-walled chamber at the apex of the heart and the atrium is the thinner-walled chamber at the base. The walls of the atrium and ventricles are smooth and shiny; they are lined with a thin layer of endothelium. Between the two chambers locate the right atrioventricular valve. This valve is made up of three flaps of endocardium. It prevents backflow of blood from the ventricle to the atrium during contraction of the ventricle (systole). Notice that the flaps are connected to the walls of the right ventricle by strands of connective tissue, the chordae tendinae. These prevent the valve from being turned inside out by the force of the blood. The superior vena cava and the inferior vena cava empty into the right atrium. Locate the exit of the pulmonary artery from the right ventricle; it will be toward the base of the heart. Though not visible here, note that the artery is separated from the ventricle by a valve, the right semilunar valve. This valve consists of three crescent-shaped flaps of endocardium.

Healthy Lung Lungs Diagram of a Smoker after Smoking Cancer Anatomy And Heart Drawing Images AFter Smoking Wee of a Weed Smoker

Healthy Lung Lungs Diagram of a Smoker after Smoking Cancer Anatomy And Heart Drawing Images AFter Smoking Wee of a Weed Smoker

Healthy Lung Lungs Diagram of a Smoker after Smoking Cancer Anatomy And Heart Drawing Images AFter Smoking Wee of a Weed Smoker

Healthy Lung Lungs Diagram of a Smoker after Smoking Cancer Anatomy And Heart Drawing Images AFter Smoking Wee of a Weed Smoker

Healthy Lung Lungs Diagram of a Smoker after Smoking Cancer Anatomy And Heart Drawing Images AFter Smoking Wee of a Weed Smoker

Healthy Lung Lungs Diagram of a Smoker after Smoking Cancer Anatomy And Heart Drawing Images AFter Smoking Wee of a Weed Smoker

Healthy Lung Lungs Diagram of a Smoker after Smoking Cancer Anatomy And Heart Drawing Images AFter Smoking Wee of a Weed Smoker

Healthy Lung Lungs Diagram of a Smoker after Smoking Cancer Anatomy And Heart Drawing Images AFter Smoking Wee of a Weed Smoker

Healthy Lung Lungs Diagram of a Smoker after Smoking Cancer Anatomy And Heart Drawing Images AFter Smoking Wee of a Weed Smoker

Healthy Lung Lungs Diagram of a Smoker after Smoking Cancer Anatomy And Heart Drawing Images AFter Smoking Wee of a Weed Smoker

Healthy Lung Lungs Diagram of a Smoker after Smoking Cancer Anatomy And Heart Drawing Images AFter Smoking Wee of a Weed Smoker

Healthy Lung Lungs Diagram of a Smoker after Smoking Cancer Anatomy And Heart Drawing Images AFter Smoking Wee of a Weed Smoker

Healthy Lung Lungs Diagram of a Smoker after Smoking Cancer Anatomy And Heart Drawing Images AFter Smoking Wee of a Weed Smoker

Healthy Lung Lungs Diagram of a Smoker after Smoking Cancer Anatomy And Heart Drawing Images AFter Smoking Wee of a Weed Smoker

Healthy Lung Lungs Diagram of a Smoker after Smoking Cancer Anatomy And Heart Drawing Images AFter Smoking Wee of a Weed Smoker