Digestive System in Mammals

General anatomy of digestive system
Ozofagus;1/3 is striated muscle, 2/3 is smooth muscle.
Small intestine; duodenum, jejenum, ileum.
The end of ileum is appendix (Secum in horse) in human.
Large intestine; colon, rectum, anusThe structure of digestive tract
Muscularis mucosa
Mucus layer
Plexus myentericus
In the large intestine, longitiudinal muscles concentrated as longitiuidinal line called tenia coli.
Concentrated circular muscle in large intestine produce haustra formation.
The length of digestive tract depends on type of food ingested by animals.
Longest in herbivours, shorter in carnivoursIngesting of food
Hunger drive is controlled by hypothalamus
Glucostatic theory of hunger suggests that an increase in blood glucose level increases the activity of the satiety center and decreases the activity of hunger center.
Low blood glucose has the opposite effects.
Aminoacid levels and lipid levels have also been suggested to influence hunger and satiety.
The hepatostatic theory of hunger control argues for a role of liver as an important sensor and modulator of the body energy stores. Distension of the stomach and small intestine, stretching of the abdominal wall, the hormone cholecystokinin and the mechanical activity of chewing and swallowing all inhibit the hunger center.
Swallowing (deglutation); primer and seconder peristaltic movements along the osophagus
Osophagal sphincter
Stomach; Contraction is more stronger in antrum than fundus
Cardiac and pyloric sphincter
Small intestine; peristalsis, segmentation and penduler contractionLarge intestine;Segmentation, Mass movement and antiperistalsis.
Anal sphincter; internal and external.

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