The large intestine.
There is more than one system that removes wastes from the body. The urinary system is probably the most familiar (urine), the digestive tract (feces), the respiratory tract (carbon dioxide) and the integumentary (skin) removes water and some electrolytes.
large intestine
The colon is the organ that removes water from undigested food in the digestive system. If the colon is unable to remove enough water, it can lead to diarrhea, whereas if too much water is removed, it can result in constipation.
There are two systems that remove wastes from the body. The lower digestive tract (the colon) removes solid wastes and sodium whiles it retains water. The urinary system removes waste from the blood by way of the kidneys.
The digestive system, basically the small intestines.
Large intestines.
The large intestine is part of the digestive system. Its main function is reabsorption of water from undigested food waste.
No single organ 'stores' food. Food flows throgh the digestive system, entering the mouth and exits the booty.
The colon is an organ that is made from many different types of tissue.
In addition to the water vascular system responsible for movement and feeding, you could expect to find a digestive system in a starfish. This system includes the stomach and digestive glands for processing food.
Large Intestine
Kidney