The digestive system of marine mammals consists of the mouth, esophagus, stomach, small and large intestine, colon, and rectum. Accessory organs are also critical for digestive function including the liver and pancreas.
Neo-Cetacean Digestive System
- Mouth: Although Neo-Cetacean have mouth and teeth, they don’t chew their food at all. Instead they swallow their food as whole.
- Esophagus: After Neo-Cetacean swallow the fish, fish go down to the stomach.
- Stomach: Neo-Cetacean have four chambers in stomach. The food would arrive the forestomach or esophageal stomach firstly. It is lined with thick ridges (rugae) and is mainly a storage compartment for food though some protein digestion does occur here. The next chamber is called the fundic or main stomach and is a dark red in color. This is the chamber where HCl is secreted along with digestive enzymes. Then food will stay at Connecting stomach for further digesting. The next chamber is the pyloric stomach which is lined with mucus cells and is usually yellow to brown in color.
- Duodenal Ampulla: it’s usually smooth in texture and is often full of bile (brownish fluid) which is secreted into this region from the liver via the hepatopancreatic duct. The food is called chyme at this process.
- Intestine: Duodenum is the most anterior part of the small intestine where it gets mixed with the products of the pancreas including bicarbonate to increase the pH. Then the chyme then makes its way to the rest of the small intestine which consists of the jejunum and ileum. Most of the absorption of nutrients occurs in the first quarter of the small intestine. The large intestine follows the small intestine and then finally reaches the colon and rectum and waste is excreted from the anus.
Connection between systems
- The digestive system works very closely with the circulatory system to get the absorbed nutrients distributed through your body.
- The digestive system also works in parallel with your excretory system (kidneys and urination). While the digestive system collects and removes undigested solids, the excretory system filters compounds from the bloodstream and collects them in urine. They are closely connected in controlling the amount of water in your body.
- Both certain bones of the skeletal system and muscles of the muscular system are involved in chewing food. The muscular system also plays an important role in swallowing food and moving the products of the digestion process along the gastrointestinal tract.
- The endocrine system interacts with the digestive system in that there are hormones that play a role the digestion process.
Comparation with Himan
Neo-Cetacean’ digestive system is shorter than human’s.
Neo-cetacean swallow food. Human chew food.
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H. (n.d.). Digestive System - Untamed Science. Retrieved December 07, 2016, from http://www.untamedscience.com/biology/human/digestive-system/
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