Digestive and Respiratory Organs of the Thorax

The trachea extends into the thorax and there divides into two bronchi that go to the lungs. The bronchi will not be visible until you have removed the heart and attached vessels in next week's lab. In the image to the right, the heart is lifted away from the lungs. Notice that each lung is divided into lobes, three on the left and four on the right. The lung tissue in the fetal pig is very dense since the lungs have not yet filled with air. If we had dissected an adult animal, the lungs would have appeared more spongy, even in a preserved animal.

The next image shows the left lung lifted ventrally and to the right. You should find the esophagus passing posteriorly. Be careful not to confuse it with the main artery of the body, the aorta, which you will examine in more detail next week.