Digestive System in Chordata (chordates)
Chordates is in some ways similar to us humans. For example, they eat through ingestion rather than absorption like some of the other phylums. There are many different types of species in the chordata system, up to 450,000! Within all those different species, there are many different ways to digest food. If you would like to learn about all 450,000 different species' digestion system, then you might want to look somewhere else. Here we are just going to name a few of the major ones like the fish, the snake (reptile), and the rabbit.
Fish have a jaw like us humans, giving them the ability to eat a variety of food such as plants, smaller fish, and other organisms. They are very similar to us because they use the esophagus to transfer the food to finger-like pouches, sometimes referred to as pyloric cacum, which are located in the stomach thus allowing which break down and absorb the nutrients within the food. The liver and the pancreas aid in the digestive process as they add enzymes that allow the food to be moved to the intestines. Then after that, the digestion process is complete. The intestines allow nutrients to be processed and turned into energy.
Snakes don't eat as often as humans and other chordatas because they eat very big meals as opposed to 3 medium meals like us. The snakes have mouths and teeth but no molars to chew the food, they have to swallow the food whole. They're jaws have the capabilities to reach more than twice the diameter of their bodies, and with the help of their thick-walled, spindle-shaped stomach, they can digest food in a different manner. Their stomach happens to be muscular and distenible which allows them to have a animal move through their body without a problem. Their small intestine is looped around to make room for the other organs. This organ however, is the one that is connected to the anus thus allowing it to empty feces for the colon to store. The small intestine is the place to be if you are looking for the nutrients and the breakdowns. The large intestines is the least muscular and most thin walled structure of the snake's digestive system. This intestine passes into what is called the cloacae chamber where it is divided into a copradaeum for receiving waste and urine and products for the genital organs.
Rabbit's digestive system is like most mammals using the mouth and esophogus to transport food to the small intestines. Again, here in the small intestines is where most of the breaking down and absorbing of the nutrients happens. Fiber is very hard to break down so most of the time is just goes directly through the small intestine straight to the colon. The rabbit however, has a special colon that can decipher what type of fiber is coming. The fiber is either, digestible or indigestible. The digestible portion has its nutrients locked away in the caecum and the other, well, that is what you see as the small little droppings they leave behind.
All while this is processing, the caecum is using the help of a special bacteria that aids in breaking down the locked away nutrients of the fiber. This is not a very pretty site to see as the rabbit's body makes special droppings known as cecal droppings that the rabbit then eats. In their new form, they pass through the body again but are able to be absorbed now.