Answer:
The longest organ is the small intestine, which can be up to 7 meters long. The reason for being so long is related to its digestive and absorption functions.
Explanation:
The digestive system is the group of organs that are in charge of the digestive process, that is, the process in which food is transformed to be absorbed and used by the organism cells.
The digestive system is in charge of food transport, digestive juices secretion, nutrient absorption, and excretion.
The whole digestive tube is approximately eleven meters long, from the mouth to the anus.
The small or thin intestine is the longest organ of the digestive tube. It can reach up to 7 meters long, up to 3 centimeters of diameter, and it characterizes for being folded. Its first portion -the duodene- receives secretions from intestinal glands, such as bile and pancreatic juices, and mix them with digestive juices of its production. All of these secretions carry huge amounts of enzymes that will degrade food and transform it into soluble substances, such as amino acids.
The reason for being so long is that this is the portion of the tube where it occurs nutrients absorption. The intestine walls are covered by villi that increase the absorption area. It also transports water from the blood to the intestinal tract, which helps in food decomposition.
