1 / 9

Human Nutrition

Human Nutrition. S upervision Prof . Dr . Mervat Salah. Intended Learning Outcomes. By the end of this lecture, students will have a general overview on roles of the gastrointestinal (GI) tract . essary micronutrients and trace elements; and.

sorena
Download Presentation

Human Nutrition

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Human Nutrition Supervision Prof. Dr. MervatSalah

  2. Intended Learning Outcomes • By the end of this lecture, students will have a general overviewon roles of the gastrointestinal (GI) tract .

  3. essary micronutrients and trace elements; and The primary roles of the gastrointestinal (GI) tract are to (1) extract macronutrients, protein, carbohydrates, lipids ,water, and ethanol from ingested foods and beverages; (2) absorb necessary micronutrients and trace elements; and (3) serve as a physical and immunologic barrier to microorganisms, foreign material, and potential antigens consumed with food or formed during the passage of food through the GI tract. In addition to its primary roles, the GI tract also participates in many other regulatory metabolic, and immunologic functions that affect the entire body.

  4. . The Gastrointestinal tract: The Ultimate Food Processor Each day a varying mixture of foods enters the gastrointestinal (GI) tract, and with remarkable efficiency the GI tract goes about its tasks 1-Sight, aroma, even sounds and thoughts of food: presence and nature of food in the mouth 2-Perception of hunger from the Gl tract; hypothalamus signals after sampling substrates and hormones 3-Presence of food in the stomach 4-Presence of partly digested food and acid in the small intestine .

  5. All these factors lead to : Start Gl hormone secretions and increase bile flow and enzyme secretions from the stomach pancreas and intestinal mucosa; also increase G l motility ,blood flow, and growth . Start GI Presence of digesta in the small intestine and colon Slows gastric emptying, limits gastric acid and enzymes secretion increases satiety, promotes feeling of satiety Provides fuel for host and cells lining GI tract, promotes growth of intestinal flora, promotes satiety, slow supper G l motility stimulates defecation

  6. The GI tract is also remarkable because of the following: . The extent and type of hormonal, motor and secretory response are appropriate for the amount and type of foods consumed. . It is remarkably efficient in digestion and absorption of foods and fluids, despite tremendous variations in types and mixtures of foods. . It has the largest surface area, greatest number of immune cells, and most hormones produced of all organs. It protects host tissues from strong acids and potent digestive enzymes, a host of antigens, potentially toxic compounds, and high concentrations of microbes that coexist in the colon just millimeters from sterile tissues

  7. humans are considerably less efficient at extracting energy from grasses, stems, seeds, and other coarse fibrous materials because they lack the enzymes to hydrollze the chemical bonds that link the molecules of sugars that make up plant fibers. Fibrous foods and any undigested carbohydrates are fermented to varying degrees by bacteria in the human colon,

  8. Assignment • Hadeerkamal abo bakr

  9. Recommended text book • Manual dietetic book

More Related