Coronal PlaneThis animation (173K; or 300K Quicktime version) travels from from the nose to the back of the head in a series of coronal sections. After watching the animation a few times (this one really flies!) see if you can follow the appearance of the brain, tongue, eyes and cervical spine - the 'neck' region of your back bone.You may notice black areas within the head sections of this animation, and in the next one of sagittal sections. The head contains the beginnings of your respiratory and digestive tracts, namely the mouth, or oral cavity. It also contains many sinuses such as the ethmoid (within your nose), sphenoid (behind your nose) frontal (behind the forehead) and maxillary (behind the cheek bone) sinuses. The sinuses have many functions, aside from becoming inflammed and irritated when you have a cold. The empty spaces make the head bone (cranium) lighter. They also function to warm and moisten the air destined for the lungs. That 'brain-freeze' feeling you get from eating ice cream is caused by the rapid cooling of the air in the frontal sinuses. The cooling triggers pain receptors, producing the 'brain-freeze.' Returning to the mouth, a long muscular tube, the esophagus, leads from the back of your throat (pharynx) to the stomach. In front of the esophagus is your trachea or windpipe which leads to the lungs. You can feel the trachea as the 'tube' in front of your neck. Midway down your trachea lies the larynx or voicebox. If you place your hand over the larynx while talking or making noise you should be able to feel the vibrations made by the vocal cords. |