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Appendix - The organ produces immunoglobulins, which can help the immune system combat infections.

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Appendix - However, other organs produce similar antibodies. Humans can also get appendicitis, a medical emergency that needs immediate attention. For that reason, many choose to get their appendix removed.

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Lungs - The lungs are one of the largest organs in the human body. In fact, the surface area of two lungs is the same size as a tennis court.

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Lungs - Lungs are key in keeping all of our cells alive. When we inhale, the lungs are the organs that transfer the oxygen into the bloodstream and remove harmful carbon dioxide.

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Lungs - That being said, humans can survive with just one lung. Matter of fact, Pope Francis is someone who has lived with just one lung for decades.

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Kidneys - Kidneys: those oddly-shaped organs that take toxins out of the bloodstream and regulate blood pressure.

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Kidneys - Lose both kidneys and you're in trouble. However, humans can function pretty well with just one kidney.

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Thyroids - Thyroids produce hormones that monitor metabolism in the human body. Thanks to medical innovation, thyroids can be "replaced" if they are damaged.

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Thyroids -

Synthetic hormones have been developed to replicate the role of thyroids.

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Gallbladder - This small organ stores and concentrates bile, which helps the body digest fatty foods.

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Gallbladder - It's important for digestion, but the gallbladder isn't 100% necessary. Intestines can get the job done themselves, and uncomfortable gallstones can actually form in the gallbladder.

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Spleen - The spleen has many uses, like producing blood and defense cells for fetuses. After a baby is born, the spleen starts to destroy harmful cells in the body.

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Spleen - Since the spleen stores so much blood, any injuries to it can be lethal. A swelling spleen can also lead to internal bleeding, so some choose to get it removed.

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Kidneys - If you lose both kidneys, dialysis can be used to keep you alive. That is, until someone donates a spare kidney.

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Reproductive organs - Sure, reproductive organs are very important, but getting rid of them actually has some health benefits. Just hear us out here…

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Reproductive organs -

Conditions like uterine fibroids and endometriosis can be treated by removing the uterus. Meanwhile, removing testicles can be effective when treating testicular cancer.

However, hormones take a huge hit by removing reproductive organs. That said, there are treatments out there for testosterone and estrogen replacements.

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Bladder - The bladder is a super important organ that removes waste and helps process urine.

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Bladder - However, a human can have their bladder safely removed. The organ can be taken out to treat cancer or certain medical disorders.

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Bladder - If you get your bladder removed, you may need to get a special bag attached to your abdomen. This procedure is called urostomy.

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The colon - The colon plays a key role in the human body. The large intestine takes digested food and helps turn it into solid waste.

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The colon - That said, humans can survive without their colon, this thanks to advances in surgery and medical technology.

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The colon - Removing your colon can help treat many medical issues, like Crohn's disease, ulcerative colitis, and diverticulitis.

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Stomach - People get their stomach removed to combat certain cancers and genetic disorders.

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Stomach - If a patient has their stomach removed, it's likely that the esophagus will be connected to the small intestine.

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Eyes - You don't need to be told how important eyes are. However, did you know that humans can survive without them entirely?

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Eyes - Eyes just aren't an essential organ for our survival—though losing one, and especially both, can make life very challenging.

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Tonsils - Tonsils can help humans prevent sickness. They catch germs and direct the body to make white blood cells to combat them.

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Tonsils -

That said, tonsils can be easily removed, with no real side effects.

See also: Unusual bodily changes after death

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