1. Digestive System

2. Digestive Process 1.Ingestion 2.Movement of food 3.Digestion 4.Absorption 5.Defecation Humans track = Alimentary Canal 30’ of digestive tract!

3. General Histology 4 tissue layers (in to out) – Mucosa – inner lining of track – Submucosa – binds to muscle layer. Contains numerous blood and lymph vessels for absorption contains nerves that control tract secretion – Muscularis – voluntary skeletal muscle in upper (mouth, pharynx and upper esophagus) and involuntary smooth in rest.] – Serosa – secretes serous fluid to allow tract to glide easily against other organs

5. General Histology All organs are covered in peritoneum made of large folds containing blood and lymphatic vessels and nerves. Parietal – lines abdominal cavity Visceral – covers digestive organs

6. Movements of the Alimentary Canal Mixing – caused by rhythmic contractions of smooth muscle in small segments of the tube Propelling – caused by wavelike contractions called peristalsis (click for awesome video!!!)peristalsis – Circular muscle changes tube diameter – Longitudinal muscle changes tube length

7. Mechanical verses Chemical Mechanical digestion occurs by breaking, tearing, or churning (teeth, churning of stomach…) Chemical digestion involves chemicals in tract breaking food down (starch into glucose by amalyse)

8. Nervous Control of Tract Controlled mainly by Vagus nerve of A.N.S. Parasympathetic nerve – increases digestive activity Sympathetic nerve – decreases activity

10. 4 classes of essential nutrients Essential Amino Acids: most animals require 8 that they cannot synthesis. Missing 1 or more can cause protein deficiency…the most common type of malnutrition.

11. 4 classes of essential nutrients Essential Fatty Acids: animals can synthesize most f.a. exception: Cannot make certain unsaturated f.a. Ex: humans require linoleic acid for membrane phospholilpids

12. 4 classes of essential nutrients Vitamins: organic molecules required in very small amounts Serve as co-enzymes Classified as water-soluble or fat-soluble See page 795

13. 4 classes of essential nutrients Minerals Inorganic nutrients required in small amounts that cannot be synthesized Vertebrates need large amounts of Ca and P for bone building and nerve and muscle function. Page 796

14. Issues with missing nutrients Undernourishment – result of a diet consistently supplied with less chemical energy than the body requires – Body uses up stored fats and carbohydrates – Body starts to use protein as fuel » Causes muscles to waste » Brain may become protein deficient Death or irreversible damage can occur

15. Issues with missing nutrients Malnourishment – long term absence of one or more essential nutrients – Can cause deformities, disease, or even death. – Ex. Lack of phosphorus in cattle = broken bones – Humans eating a mostly rice diet can cause vitamin A deficiency = blindness or death.

16. Goiter – thyroid gland effected by an iodine deficit

17. BODY STORY: GERMS

18. Molecular gastronomy is a sub discipline of food science that seeks to investigate, explain and make practical use of the physical and chemical transformations of ingredients that occur while cooking, as well as the social, artistic and technical components of culinary and gastronomic phenomena in general.food sciencephysicalchemicalcooking