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What would happen if we did not have a digestive system?
Question Date: 2014-06-10
Answer 1:

The digestive system is my favorite system! Without it you would not survive. Our digestive system is how we break down food into nutrients that feed our cells and give us energy to move, talk, grow, think, reproduce, and all the other crazy things that humans do.

Although each of the parts of the digestive system has specific and important functions, shockingly, you can survive without some of the parts. For example, morbidly obese individuals can have their stomach entirely removed in a procedure called a gastric bypass. In this surgery, the small intestine is linked directly to the esophagus thus “bypassing” the stomach. You can also live without your appendix. In fact, it sometimes negatively impacts health as it can become infected (have you ever known someone who had their appendix burst?). The appendix was thought to be a “vestigial organ” meaning that at one point in evolutionary history, we humans had a need for it, but now we don’t; however, there is recent evidence that the appendix is an important hotbed for beneficial bacteria that help us digest food. (The appendix may not be so bad after all!, read on the link to learn about click here

Answer 2:

A complex digestive system was evolved very early on to recover and sort nutrients in food. It was one of the first parts of organisms to evolve, even much before complex brains. If you had no digestive system, you would have no ability to get the nutrients and sugars in food, and you would die. The digestive system is very long, however. Some people have gotten into car accidents and damaged their intestines, and had to have part of them removed. The entire digestive system may be over 30 feet long (it's all coiled up). Thankfully, we can live with only part of a digestive system. However, if you have a significant part removed, your food passes through faster and you get less nutrients out of it, so you have to eat a lot more food than normal people and you have to go to the bathroom very frequently.

Answer 3:

To answer your question, let's think about the purpose of the digestive system for keeping us alive. We use our digestive system mostly to take in nutrients, energy and water. All living things require nutrients, energy and water, but not all living things have digestive systems the way we think of in the human body.

So, if we didn't have digestive systems, but wanted to keep on living, we would need a different way of taking these things in. Maybe this would look like plant life, where we take energy from the sun and water and nutrients from a root system. Or maybe it would look like fungi, which take up small sugar and amino acid compounds through their cell walls and break them down for energy. Or maybe something altogether different and unknown. All we know as that for life (as we know it) to exist, organisms must receive external water, energy and nutrients. Evolution has produced several systems that work quite well for a vast number of organisms, but perhaps there are other options that nature has either discarded over time in place of more successful systems, or which nature hasn't gotten around to testing yet. Fun to think about!

Answer 4:

This is an interesting question. The digestive system is responsible for the breakdown of food into components that can be absorbed and assimilated into the body, and is connected to the excretory system, which excretes waste, or material that is not used by the body. Without the digestive system, then, we wouldn't really have a way of acquiring the compounds and energy necessary for our bodies to function.

Answer 5:

For humans, and most highly organized animals such as birds, mammals, and mostly other animals, the digestive system is the most important part of the system. We have something called a complete gut (we have a mouth and an anus). When we eat our food it travels down the esophagus down to our stomach and intestines. In the small intestine 90% of our food is absorbed back into our body. If we didn't have a digestive system the food wouldn't be absorbed the way we need it to be for bodily functions. We needs nutrients, such as vitamins and proteins to carry out functions. Most primitive animals did not have a digestive system or a complete gut, but they lived because their structures are so far less advanced that they didn't need a proper digestive system. Another reason is that we eat a lot of different types of food which need to be broken down. Our digestive system allows us to eat the variety of foods because it can break down the foods and then absorb essential nutrients back into our bodies. You hair, skin, nails, body weight, body structure, strength, and overall health mostly comes from the food you eat, which is why it is very important to eat healthy. The food we eat is our fuel and if we eat the wrong "fuel", such as chips, donuts, and other excessive sugars and bad carbohydrates, our digestive system doesn't have the right nutrients to absorb back into our bodies. Our digestive system is very critical in our overall health.

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