This site has a diagram.
The digestive tract runs nearly the entire length of the body and includes the mouth, esophagus, stomach, small intestine, large intestine and anus -- all stretchable to digest prey larger than a snake's diameter (See Feeding section). When the snake's mouth is full, it has to extend its trachea (breathing tube) below the food and out in order to keep breathing. Snakes do not have a diaphragm like people do, so they circulate air in and out of t...

This site has a diagram.
The digestive tract runs nearly the entire length of the body and includes the mouth, esophagus, stomach, small intestine, large intestine and anus -- all stretchable to digest prey larger than a snake's diameter (See Feeding section). When the snake's mouth is full, it has to extend its trachea (breathing tube) below the food and out in order to keep breathing. Snakes do not have a diaphragm like people do, so they circulate air in and out of the lungs by narrowing the rib cage to push air out and then widening it again to create a vacuum to suck air in. After each breathing cycle, snakes experience apnea -- a stop in breathing -- that lasts from a few seconds to as long as a few minutes. To process the oxygen, all snakes have an elongated right lung; many also have a smaller left lung, and a few even have a third lung along the trachea.
http://science.howstuffworks.c...

Recently, scientists studied the digestive system (specifically the small intestine) of certain snakes, such as vipers, boa constrictors, and pythons. In these snakes the period of time between meals can range from a few weeks to several months. It was found that during the long periods of fasting that the lining, or mucosa, of the small intestine becomes atrophied (i.e., decreases in thickness and activity), conserving the body's energy and resources.

Snakes such as these consume large meals ranging from 50% to as much as 160% of their body weight. To accommodate such a large meal the snake needs a fully functional digestive system. It was found that feeding stimulates rapid growth of the intestinal lining. The weight of the small intestine can actually double in a few hours after a meal due to the rapid growth of the mucosa. One study demonstrated that the activity of the intestinal cells also increases after a meal. It was found, for example, that the uptake of nutrients, such as amino acids, increased by as much as 16 fold over a period of three days.
http://www.doesgodexist.org/Ma...

Snake

Snakes eat all parts of their pray and need a specialised digestive system to gain the most nutrients from their food. Their teeth are very thin and usually curve backwards. Their function is not to grind down food as it is in most animals, rather it is to capture prey. The food is swallowed whole, thus the teeth perform a specialised function. They have powerful digesti...

Snake

Snakes eat all parts of their pray and need a specialised digestive system to gain the most nutrients from their food. Their teeth are very thin and usually curve backwards. Their function is not to grind down food as it is in most animals, rather it is to capture prey. The food is swallowed whole, thus the teeth perform a specialised function. They have powerful digestive enzymes to break down the hair, feathers, bones, organs and other parts of their food.

The salivary glands also produce strong enzymes which are also used to kill the organism. If saliva enters the wounds of the animal it will begin the digestive process and cause severe tissue damage, which can often lead to the death of the animal. These toxic substances are found in the saliva of many non poisonous snakes. In poisonous snakes it is the salivary glands which have developed into venom sacks, with the venom being a highly toxic form of saliva.

I would like you to see this picture where a python is feeding on an aligator but both die and python's body ruptures. Lovly high resolution photo at link below:
http://blogs.herald.com/dave_b...