I love you yawning burm, nice clear big mouth we can look at some snake anatomy.
Snakes have two sets of teeth on the top, and one set on bottom. You can see the rows of teeth defined here as ridges hidden with gums (when you have a ton of thin fish hook style teeth, you need some extra buffering to hold them in place. The gums slide down along the bone when the teeth press against food). The bottom jaw bones can move somewhat independently from one another, to help crawl down the food while the top inner set works more as an anchor.
The hole in the roof of the mouth is called the choanal slit. The nostrils pass into this opening, and when the mouth is closed it flows into the glottis and on into the trachea to breathe. In this photo the glottis is closed, so that little nub between the bottom teeth. That’s where they breathe, not that big gaping swallowing hole esophagus. The glottis is also where the tongue comes out from. Snakes tend to have a little notch in the front upper lip to clear a path for the tongue to flick freely.
This is why people say to check the tongue if the snake has RI. Since it hangs out in the breathing apparatus, the forked sections can get glommed together when there’s an overproduction of snot.
And those big bulges arching around the esophagus are jaw muscles.