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-4 short answer Questions (15 points each) (all lectures for course) Final Exam -3 hours 120 multiple choice (all lectures after 17 February to the last lecture of the course inclusive) -4 short answer Questions (15 points each) (all lectures for course)  

Lecture 3 14 JANUARY 2019 INGESTION/DIGESTION/ ABSORPTION/TRANSPORT/ METABOLISM/EXCRETION 14 JANUARY 2019

Overview of lecture 3 1) INGESTION 2) DIGESTION 3) ABSORPTION 4) TRANSPORT 5) METABOLISM 6) EXCRETION 7) REGULATION OF IDATME    

INGESTION mouth- chewing and swallowing oral or nasal tube intravenous    

DIGESTION -process by which food is broken down into absorbable units -muscular action of digestion -peristalsis -stomach action-churning -segmentation –small intestine -sphincters-opening and closing valves http://nutrition.jbpub.com/resources/animations.cfm?id=1&debug=0 -secretions of digestion

Figure 3.1: The Gastrointestinal Tract. Fig. 3-1, p. 71

Digestive glands and their secretions (enzymes) -saliva -gastric – water, HCl and pepsin-proteins -pancreatic juice/intestinal enzymes carbohydrases lipases proteases

Link only available in class file:///D:/Media/Animations/chapter3/Digestive_Sandwich/0308.html Link only available in class

Absorption I) DEFINE-passage of nutrients from gi tract into blood or lymph A) simple diffusion-water, small lipids/fat soluble vitamins B) facilitated diffusion-fructose/water soluble vitamins C) active transport-glucose/amino acids do not confuse simple and facilitated diffusion or active transport with the transport discussed below II) ANATOMY-goblet cells/crypts/villi and microvilli

Figure 3.10: The Small Intestinal Villi. Absorption of nutrients into intestinal cells typically occurs by simple diffusion or active transport. Fig. 3-10, p. 79

Transport defined getting nutrients, via blood or lymphatic systems, to where needed, when needed, in the form needed and in the correct quantities needed. WWFQ

ANATOMY OF TRANSPORT TWO ROUTES -BLOOD AND LYMPH

ANATOMY OF TRANSPORT BLOOD ROUTE Heart to artery to capillaries (intestine) to vein to capillaries (liver)-in liver get detoxification and preparation of nutrients for body use-vein to heart from liver for distribution to the rest of the body . water soluble nutrients and smaller products of fat digestion go this route

ANATOMY OF TRANSPORT LYMPH ROUTE Lymph (tissue spaces to blood) intestine to heart directly for distribution to rest of body-larger fat digestion products and fat soluble vitamins ADEK use this route

file:///D:/Media/Animations/chapter3/Vascular_System/311.html Link only available in class

METABOLISM collection of all the reactions and their regulation that go on in the body constant anabolism and catabolism

METABOLISM ANABOLISM – BUILDING UP eg -amino acids to protein into muscle -glucose into glycogen -(carbohydrate storage) -fatty acids into triglycerides (fat storage)

METABOLISM CATABOLISM- TEARING DOWN eg -muscle to protein to amino acids -carbohydrate (glycogen into glucose) -triglycerides into fatty acids

METABOLISM ANABOLISM AND CATABOLISM -assisted by vitamins, minerals -water used in some catabolic reactions to split molecules -water formed by catabolism sometimes -water formed in some anabolic reactions

Figure 10.13: Animated! Metabolic Pathways Involving B Vitamins. These metabolic pathways were introduced in Chapter 7 and are presented here to highlight the many coenzymes that facilitate the reactions. These coenzymes depend on the following vitamins: • NAD and NADP: niacin • FMN and FAD: riboflavin • TPP: thiamin • THF: folate • CoA: pantothenic acid • PLP: vitamin B6 • B12: vitamin B12 • Biotin Pathways leading toward acetyl CoA and the TCA cycle are catabolic, and those leading toward amino acids, glycogen, and fat are anabolic. For further details, see Appendix C. Fig. 10-13, p. 347

Figure 10.13: Animated! Metabolic Pathways Involving B Vitamins. These metabolic pathways were introduced in Chapter 7 and are presented here to highlight the many coenzymes that facilitate the reactions. These coenzymes depend on the following vitamins: • NAD and NADP: niacin • FMN and FAD: riboflavin • TPP: thiamin • THF: folate • CoA: pantothenic acid • PLP: vitamin B6 • B12: vitamin B12 • Biotin Pathways leading toward acetyl CoA and the TCA cycle are catabolic, and those leading toward amino acids, glycogen, and fat are anabolic. For further details, see Appendix C. Fig. 10-13, p. 347

Figure 10.13: Animated! Metabolic Pathways Involving B Vitamins. These metabolic pathways were introduced in Chapter 7 and are presented here to highlight the many coenzymes that facilitate the reactions. These coenzymes depend on the following vitamins: • NAD and NADP: niacin • FMN and FAD: riboflavin • TPP: thiamin • THF: folate • CoA: pantothenic acid • PLP: vitamin B6 • B12: vitamin B12 • Biotin Pathways leading toward acetyl CoA and the TCA cycle are catabolic, and those leading toward amino acids, glycogen, and fat are anabolic. For further details, see Appendix C. Fig. 10-13, p. 347

Excretion-in whole or as a metabolite -urine-protein (urea), minerals, water, carbohydrate, vitamins -feces-carbohydrates, lipid, vitamins, protein,water, minerals -sweat-minerals,water -saliva?-minerals?, carbohydrates?, lipids?, protein?, water?, vitamins? -breathing-O2 and CO2  

Regulation of IDATME -maintenance of constant internal conditions -all hinges on homeostasis- define- -maintenance of constant internal conditions -can be disrupted by physical immaturity, aging, illness, nutrition

Regulation of IDATME INGESTION FOOD INTO BODY- demanded by hunger signals (really metabolic signals) indicating dropping supplies of nutrients INGESTION REGULATION LEADS TO DIGESTION REGULATION

Regulation of IDATME DIGESTION -e.g. stomach pH homeostasis – pH 1.5 hormonal/neuronal regulation- -important for digestion

Regulation of IDATME Digestion regulation continued Pyloric sphincter hold food ready for duodenum duodenum has pH sensors -too acid-close pyloric sphincter and bicarbonate added to chyme making chyme neutral and then pyloric sphincter opens again why? -pH important for enzyme function

Figure 3.1: The Gastrointestinal Tract. Fig. 3-1, p. 71

Regulation of IDATME -hormonal regulation of 3 types of Digestion regulation continued -hormonal regulation of 3 types of enzymes- type and amount of enzymes from pancreas -bile-fat emulsion-amount under hormonal regulation -fat slows peristalsis-hormonal -also neuronal regulation of peristalsis -digestion regulation leads to absorption regulation

Regulation of IDATME Absorption (transport across the small intestine into blood or lymph) -simple diffusion, facilitated diffusion, active transport

Regulation of IDATME ABSORPTION -simple - move with concentration gradient (regulation- high in small intestine and low on other side) – e.g. water and small lipids go across this way -facilitated - move with concentration gradient- high in small intestine and low on other side-presence of carrier (regulation -amount and activity of carrier)- e.g. fructose and water soluble vitamins go across this way.

Regulation of IDATME ABSORPTION continued -active - move against a concentration gradient low in small intestine and high on other side - a carrier and energy required (regulation-amount and activity of carrier and sufficient energy) -e.g. calcium, amino acids and glucose go across this way.

REGULATION OF IDATME ABSORPTION REGULATION LEADS TO TRANSPORT REGULATION

Regulation of IDATME Metabolism -enzymes run the show -enzymes in humans are proteins (always) that allow reactions to go faster than they would without the enzymes -supply of and demand for metabolic products control enzymatic rates -high demand with low supply leads to faster enzymatic rates -low demand with high supply leads to slower enzymatic rates -metabolism regulation leads to excretion regulation

Regulation of IDATME Excretion -dumping of metabolic waste products -primarily done by liver and kidneys and intestine ultimately regulates ingestion since retention of metabolic waste products variously upsets metabolism and may make one feel bloated or nauseous with possible vomiting

Regulation of IDATME ingestion regulates digestion digestion regulates absorption absorption regulates transport transport regulates metabolism metabolism regulates excretion excretion regulates ingestion So we have now gone full circle

Summary of lecture 3 1) INGESTION 2) DIGESTION 3) ABSORPTION 4) TRANSPORT 5) METABOLISM 6) EXCRETION 7) REGULATION OF IDATME NEXT LECTURE - 16 JANUARY- Canada’s food guide and DRIs, food labels six dietary principles, physical activity guidelines