Buccal Cavity – The buccal cavity, in which is also known as the mouth, is the start of the digestive system. This is where food is broken down by the teeth into smaller pieces. Oesophagus – The oesophagus, which can be referred to as the gullet or food pipe, is a long, muscular tube, which travels down through the throat, that connects the mouth and the stomach together. It’s role is to carry food and liquid to the stomach through using muscle contractions. Glands in which are in the walls of the oesophagus produce mucus in order to help food move down more easily when swallowing. Stomach – The stomach is a known as a muscular organ in which is situated towards the left side of the upper abdomen, under the ribs. The top of the stomach is attached to the oesophagus and then bottom of the organ is connected to the small intestine, As food arrives at the end of the oesophagus, it enters into the stomach where the muscles will produce a wave-like contraction, known as peristalsis, which will move the food onto the next digestive station. Duodenum – The duodenum is the first and shortest part of the small intestine where it receives partially digested food (also referred to as chyme) from the stomach. It’s important role within the digestive system to the chemical digestion of chyme so that it prepares the small intestine for the absorption. Pancreas – The pancreas secrete enzymes and digestive juices into the small intestine. In there, it remains breaking down carbohydrates, proteins and fats within the food that is left within the stomach. The pancreas also creates the hormone insulin where it secretes it into the bloodstream in order to help regulate the glucose or sugar levels in the body. Liver – The liver is a the largest glandular, vertebrate organ in which is situated in the upper right abdominal cavity and is protected by the ribcage. It’s main responsibility relating to the digestive system is to help by processing the nutrients that are absorbed from the small intestine. The liver also is to filter the blood arriving from the digestive tract and secretes bile that goes back into the intestine. Gallbladder – The gallbladder is a storage organ situated near the liver. It has a very vital role in the digestion of food where it contains bile produced by the liver until it is needed for the digestion of fatty foods in the duodenum within the small intestine. Small Intestine – The small intestine is an extremely long muscular, convoluted tube that absorbs roughly about 90% of the nutrients from various different foods in which humans eat. It helps to break down food by using the enzymes from the pancreas and the bile from the liver. The small intestine is made up of three different segments; duodenum, jejunum and ileum. The duodenum is responsible for the constant breakdown process and the other two, jejunum and ileum, their function is to absorb the nutrients into the bloodstream. Large Intestine – The large intestine, which can also be referred to as the large bowel, is the last section of the digestive system in humans. When the chyme from the small intestine gets transferred to the large intestine, there is rarely any nutrients remaining. Therefore, the large intestine takes the water from the food mixture and returns it into the body. During the process of the body receiving the water, the waste products ultimately get left behind where they will harden as they become dry so it is easier for the body to remove them. Kidneys – Kidneys are small organs in which are roughly the size of a fist. They are situated under the rib cage and are on each side of the spine.