(2.38)
Now that we’ve seen the hyoid bone and the muscles that hold it in place and move it, we’ll move on to look at the tongue.
The shape of the mobile anterior part of the tongue is familiar to us from everyday encounters. What’s perhaps surprising is how much of the tongue we don’t see from in front. The tongue goes a long way back, and a long way down.
To understand the overall shape of the tongue, let’s look at a specimen that’s been divided in the mid-line. All this is the tongue, right back to here. The tongue consists almost entirely of muscle, covered by specialized mucous membrane. The freely mobile anterior part of the tongue almost fills the oral cavity. The massive posterior part of the tongue, which is much less mobile, faces backwards into the oropharynx.
This structure below and behind the back of the tongue is the epiglottis. We’ll see it in the next section.
To get a look at the intact tongue, we’ll look at a specimen consisting of just the tongue, the mandible, and the hyoid bone. Here’s the mylohyoid muscle. The body of the hyoid bone is here; here’s the greater horn.
We’ll look at the outside of the tongue first. The tongue is covered with mucous membrane, on top, on the sides, and also here in front, on the underside. The mucous membrane of the tongue is continuous with the mucous membrane that covers the floor of the mouth, and the alveolar process.
There’s a deep valley between the alveolar process and the side of the tongue. This projecting fold in the mid-line is the frenum. On either side of it the submandibular ducts open, as we’ll see later.
The mucous membrane over the root of the tongue is thin ...
(2.38)
Now that we’ve seen the hyoid bone and the muscles that hold it in place and move it, we’ll move on to look at the tongue.
The shape of the mobile anterior part of the tongue is familiar to us from everyday encounters. What’s perhaps surprising is how much of the tongue we don’t see from in front. The tongue goes a long way back, and a long way down.
To understand the overall shape of the tongue, let’s look at a specimen that’s been divided in the mid-line. All this is the tongue, right back to here. The tongue consists almost entirely of muscle, covered by specialized mucous membrane. The freely mobile anterior part of the tongue almost fills the oral cavity. The massive posterior part of the tongue, which is much less mobile, faces backwards into the oropharynx.
This structure below and behind the back of the tongue is the epiglottis. We’ll see it in the next section.
To get a look at the intact tongue, we’ll look at a specimen consisting of just the tongue, the mandible, and the hyoid bone. Here’s the mylohyoid muscle. The body of the hyoid bone is here; here’s the greater horn.
We’ll look at the outside of the tongue first. The tongue is covered with mucous membrane, on top, on the sides, and also here in front, on the underside. The mucous membrane of the tongue is continuous with the mucous membrane that covers the floor of the mouth, and the alveolar process.
There’s a deep valley between the alveolar process and the side of the tongue. This projecting fold in the mid-line is the frenum. On either side of it the submandibular ducts open, as we’ll see later.
The mucous membrane over the root of the tongue is thin and mobile. Over the sides and the upper surface the mucous membrane is thick, firmly attached to the underlying muscle, and covered by projections called papillae. The largest of these, the valleculate papillae, are in a row back here. This shallow pit in the mid-line is the foramen cecum.