Structure: The structure of the small intestine is made up of the epithelium which contains enterocytes which are intestinal cells that are located on the villi. The villi are the finger like projections that create more surface area for absorption. There is something called a brush brier which is microvilli on the enterocytes that are simply for even more absorption. The small intestine then has a layer of connective tissue composed of nerves, blood and lymph that holds the intestine together. The next layer is the smooth muscle layer which is where peristalsis occurs. The smooth muscle is involuntary and therefore we swallow when we swallow. The last layer is a connective tissue layer for protection.
Duodenum: The duodenum is the first part of the small intestine. It is the site of the active digestion which means that the maximum of digestion (mainly enzymatic digestion). This is pancreatic secretions from the pancreas which secrete justices. in these juices there are zymogens that are inactive enzymes. These zymogens are activated for the digestion of proteins. More on the zymogens and enzymes--which are they specifically.
Jejunum: The jéjunum absorbs most of the nutrients from the body. It is the longest part with the most surface area absorption.
Illeum: the ileum is the last nutrient absorption.
Large Intestine (Group 2 - Angie E)
The large intestine consists of four areas; a large caecum or blind sac near the ileocolic valve; an ascending colon on the right side; a short transverse colon; and a descending colon heading posteriorly. The cecum is quite large in herbivores, like the rat, and may contain microorganisms, which further breakdown the plant material not already digested by the enzymes of the small intestine. The major function of the large intestine itself is the re-absorption of the large quantities of water secreted into the gut during digestion. Thus, as undigested material moves along the colon, water is removed from it, resulting in a mass of waste material, the feces. Feces are stored in the rectum (the terminal portion of the colon) until eliminated through the anus. (which is not part of the LI).
Post Large Intestine (Group 2 - Abigail F)
The feces of a rat are skinny pellets, about 3/8 inches long and 1/8 inch in diameter, rounded tips, slightly buldging in the center, fresh ones are dark and get lighter with age.
Hindgut Fermenters - Rats
Pre-Small Intestine (Group 2 - Brooke F)
Small Intestine (Group 2 - Emily D)
Structure: The structure of the small intestine is made up of the epithelium which contains enterocytes which are intestinal cells that are located on the villi. The villi are the finger like projections that create more surface area for absorption. There is something called a brush brier which is microvilli on the enterocytes that are simply for even more absorption. The small intestine then has a layer of connective tissue composed of nerves, blood and lymph that holds the intestine together. The next layer is the smooth muscle layer which is where peristalsis occurs. The smooth muscle is involuntary and therefore we swallow when we swallow. The last layer is a connective tissue layer for protection.Duodenum: The duodenum is the first part of the small intestine. It is the site of the active digestion which means that the maximum of digestion (mainly enzymatic digestion). This is pancreatic secretions from the pancreas which secrete justices. in these juices there are zymogens that are inactive enzymes. These zymogens are activated for the digestion of proteins. More on the zymogens and enzymes--which are they specifically.
Jejunum: The jéjunum absorbs most of the nutrients from the body. It is the longest part with the most surface area absorption.
Illeum: the ileum is the last nutrient absorption.
Large Intestine (Group 2 - Angie E)
The large intestine consists of four areas; a large caecum or blind sac near the ileocolic valve; an ascending colon on the right side; a short transverse colon; and a descending colon heading posteriorly. The cecum is quite large in herbivores, like the rat, and may contain microorganisms, which further breakdown the plant material not already digested by the enzymes of the small intestine. The major function of the large intestine itself is the re-absorption of the large quantities of water secreted into the gut during digestion. Thus, as undigested material moves along the colon, water is removed from it, resulting in a mass of waste material, the feces. Feces are stored in the rectum (the terminal portion of the colon) until eliminated through the anus. (which is not part of the LI).Post Large Intestine (Group 2 - Abigail F)
The feces of a rat are skinny pellets, about 3/8 inches long and 1/8 inch in diameter, rounded tips, slightly buldging in the center, fresh ones are dark and get lighter with age.