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Levels of Organization in the Human Body

Levels of Organization in the Human Body. Brief Introduction to Chemistry of Biology. H= 1 O= 2 N= 3 C=4. The carbon atom a is made up of the 3 sub-atomic particles: protons , neutrons and electrons.

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Levels of Organization in the Human Body

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  1. Levels of Organization in the Human Body

  2. Brief Introduction to Chemistry of Biology • H= 1 • O= 2 • N= 3 • C=4 The carbon atom a is made up of the 3 sub-atomic particles: protons, neutronsandelectrons The valance electrons= e-s in outermost shell. These determine the chemical properties of an atom and the bonds they make with other atoms

  3. 3 Types of Chemical Bonds: • Covalent bonds – a sharing of electrons between, strong bonds. Non-Polar: equal sharing of electrons. e.g. C=C Polar: unequal sharing of electrons. e.g. H2O • Ionic bonds – complete transfer of electrons, relatively weak bond (crystals strong), break in water. e.g., NaCl becomes Na+ and Cl- in water! • Hydrogen bonds – attractive forces between H atoms and O or N atoms. Very weak but important.

  4. CarbohydratesSimple and Complex Monosaccharides* - simple sugars (monomers). 1. Glucose – the molecule as a source of E in the human body. 2. Fructose – a simple sugar found in fruits (fruit sugar). 3. Galactose – a component of milk sugar. Disaccharides - 2 monosaccharides joined by a glycocydic bond. 1. Sucrose (table sugar) = glucose + fructose 2. Lactose (milk sugar) = glucose + galactose 3. Maltose (grain sugar) = glucose + glucose Polysaccharides** - complex carbohydrates – polymers of glucose. 1. Glycogen - E storage for glucose in animal cells, liver, skeletal mus. 2. Starch - E storage for glucose in plant cells, e.g., potatoes! 3. Cellulose - structural component of plant cell walls, e.g., dietary fiber! *Consist of 3, 5 or 6 C atoms **Macromolecules formed by 9 or more monosaccharides

  5. How Glucose is Made? Photosynthesis:

  6. Where are the Carbs in our Diet? Ug, not this useless, ridiculous food structure again?

  7. A Better Food Structure? COCONUT OIL!

  8. Monosaccharides Single sugar molecules Can be classified by number of C atoms in a molecule: n = 3 trioses, e.g. glyceraldehyde (‘tri’ = 3) n = 5 pentoses, e.g. ribose and deoxyribose ('pent' = 5) n = 6 hexoses, e.g. fructose, glucose and galactose ('hex' = 6) The monosaccharides Important in Nutrition are the Hexoses: • Glucose - found in all cells; main source of E for brain and RBC’s. • Fructose - found in fruit and honey. • Galactose - found in milk. Glucose is C6H12O6

  9. The Structural Differences between Glucose, Fructose, and Galactose

  10. Glucose– what all the polymers are made out of! Note different orientation of OH group = the α and βglucose molecules. *Important when forming polymers - creating dietary differences between starchand cellulose.

  11. Fructose is naturally the most sweet tasting of all the sugars!

  12. High Fructose Corn Syrup (HFCS) HFCS 42 - beverages, processed foods, cereals, baked goods HFCS 55 - used in soft drinks HFCS 90 - extremely sweet e.g. ‘crystalline fructose’ (more rare)

  13. HFCS Promotes Diseases; Makes Diabetes Mellitus Worse  fat deposits in liver, increasing buildup of lipoproteins . Can lead to plaque buildup and narrowing of blood vessels.  Risk of Metabolic Syndrome – by consuming too much HFCS in food and drinks. HFCS worsens diabetes. Damages Immune System -  asthma, food allergies, multiple sclerosis (MS). Speeds-up aging process – Your poor liver and other vital organs must work much harder than they should. Mercury(Hg) from commercial processing found in HFCS.

  14. Disaccharides Two sugar molecules linked together… Nutritionally Important ones are: Maltose - 2 glucoses molecules (alpha bond) Found in seeds and grain: “Grain” sugar. Lactose - glucose and galactose (beta bond) Found in dairy products: “Milk” sugar. Sucrose - glucose and fructose (alpha bond) Found in plants: “Table” sugar.

  15. Dehydration Synthesis Reactions take Monosaccharides and make Disaccharides

  16. Oligosaccharides • From 3 to 10 monosaccharides long. • Have a sweet taste and unique ‘mouth feel’. • Food Examples: onions,artichokes,chicory root, • legumes, asparagus, wheat and jicama. Nutritional Benefits

  17. Basic Category Examples Fructo-Oligosaccharides(FOS), in veggies, short chains of fructose. Galacto-Oligosaccharides (GOS), short chains of galactose. 2 Important specific examples are: 1. Raffinose- indigestible (galactose-glucose-fructose). 2.Stachyrose- indigestible (galactose-galactose-glucose-fructose). Nutritional Benefits- Eating oligosaccharidesallows the undigested portion to feed beneficial bacteria(intestinal microflora) and can simultaneously reduce population of harmful bacteria.

  18. Polysaccharides • Starch – storage form of glucose in plants. • Amylose-straight chain • Amylopectin-branched • Glycogen– storage form of glucose in animals; • highly branched chain. • Cellulose– structural component of plant cell walls.

  19. All of the Polysaccharides in Human Nutrition are made up of many molecules of … GLUCOSE Therefore, when these molecules are broken down, all they liberate is… Glucose

  20. Glycemic Index (GI) indicates how quickly a certain food turns into sugar (glucose) in a person’s body. Glycemic Load(GL) indicates the total amount of glucose in the food. Calculate the total amount in terms of average serving. Glycemic Load = Glycemic Index x Carbohydrates / 100 Examples Processed Food Whole Food 76 GI x 23 net carbs /100 = 17.5 38 GI x 15 net carbs /100 = 5.7

  21. Refined Processed Foods White Bread Candy and Soda Low fat Yogurt Girl Scout Cookies Whole Foods Complex Organic Vegetables Brown Rice or Quinoa Nuts and Legumes Fresh Organic Fruits

  22. Starch Plants store glucose in chains of starch. Amylose: Straight chains in starch; 40% of starch is amylose More resistant to digestion vs amylopectin Amylopectin: Branched chains of in starch; 60% of starch is amylopectin Easier to digest

  23. Polysaccharides Starch

  24. Polysaccharides • Examples of Starchy Foods: • Grains - wheat, rice, barley, oats, corn, • and potatoes,beans • Bread, cereal and pasta, crackers, biscuits, cookies, • cakes, piecrust, all things made with flour (amylose). • The amylose is broken down quite slowly • Therefore, the higher amylose more slowly it is digested. • Long grainrice - which tend to stay more separate, • higher in amylose, lower glycemic index. • Short grainrice - which tend to make creamier, stickier rice • lower in amylose, higher glycemic index.

  25. Cooking Techniques can affect Starch Digestion Pasta is a processed food however, when cooked "al dente" (slightly firm) it’s digested more slowly, plus starch molecules tightly packed, only about half is rapidly digested. Most Bean starch structure only slowly broken down into sugars. Some cooked starches, such as potatoes and rice, when cooked and cooled, a small percentage of the starch takes longer to digest. New Vs. Mature Potatoes - ‘new’ have starch more like amylose in structure than mature, and they are somewhat less glycemic. * Similar to “Resistant Starch” like under-ripe bananas

  26. Polysaccharides Glycogen is amylopectin with very short distances between the branching side-chains. Stored in: Liver, Skeletal Muscle and Uterus. Glucose easily passes into cells and is used in metabolism. Glycogen is highly branched compared to starch

  27. Polysaccharides Any spare glucose is grabbed by the liver which has a limited capacity to store it as Glycogen. Inside Hepatocytes of Liver, glucose can be polymerized to make glycogen which acts as a carbohydrate energy store.

  28. Polysaccharides Cellulose– Contains Various Fibers… What is Fiber? Fibers or ‘roughage’ refers to a diverse group of indigestible carbohydrates found in plant foods. The molecules are linked together by chemical bonds our enzymes can not break Therefore, they pass through our G.I. tract un-digested system by us.

  29. You can think of the main difference between starch and cellulose this way: The Glucose in Cellulose has every other glucose molecule ‘upside down’, and we do not have the enzyme to break that arrangement! Is this Starch or Cellulose?

  30. Fibers are polysaccharide molecules where the sugars are linked together by chemical bonds our enzymes can not break. Including vegetables, fruits, legumes, whole grains, nuts and seeds. This is a category of carbohydrates that humans cannot digest. Recommended daily intake is: 38 g/day for men and 25 g/day for women. most people only get 15 g/day.

  31. Classifications of Fiber Fibers can be divided by solubility • Insoluble • Soluble • Insoluble fibers: include compounds such as: • Lignin, Cellulose and Hemicellulose • Adds bulk to the fecal material, helps keep it moving through the colon. • Found in vegetables and whole grains.

  32. Classifications of Fiber Soluble fiber includes: Pectins*, Gums**, and Mucilages*** (e.g. psyllium) Slows rate that chyme is released from stomach • Slows absorption of glucose • Can lower cholesterol • Found in fruits, citrus fruits, oat products, and beans *causes jams and jellies to gel **e.g. xanthan gum, gums things *** a thick, gluey substance produced by nearly all plants

  33. Classifications of Fiber Fermentable Fiber ~100 trillion bacteria reside in our gut (large intestine). These bacteria are crucial for optimal health in humans. Role in: Body Weight Blood sugar control Immunity Brain Function Mental health The friendly gut bacteria (gut flora) often referred to as the “forgotten organ”. The fiber reach the large intestine mostly unchanged. Cellulose - insoluble fiber e.g., in skin of fruit Pectin -soluble fiber e.g., in flesh of fruit

  34. Our good gut bacteria are able to digest use these fibers as fuel via fermentation! This ↑ the # and balance of friendly gut bacteria, They make Vitamin K and short chain fatty acids with powerful health benefits for us, in return for all that yummy fermentable fiber. Fermentable fibers include pectins, beta-glucans, guar gum, inulin and oligofructose. The best whole-food sources of fermentable fibers are beans and legumes. 1 Cup/day = DRI! By-products of fiber fermentation = gas. short chain FA’s Vit K

  35. In Summary: Fibers that are soluble, viscous and fermentable appear to be the healthiest. Good sources of healthy fibers include vegetables, fruits, oats, legumes, nuts, dark chocolate, avocados, chia seeds.

  36. Carbohydrate Digestion • Begins in the mouth. • Teeth grind food and mix with saliva. • Saliva contains lingualamylase. • Swallowed – the Bolus goes down the esophagus to stomach. No carbohydrate-digesting enzymes in the stomach. • The pancreas releases pancreatic amylase as carbs enter the small intestine. • Enzymes break down the disaccharides into monosaccharides. • Absorption of starch and simple sugars occurs in small intestine. • Only the indigestible fiber remains in Large Intestine.

  37. Absorption of Carbohydrates

  38. Absorption of Carbohydrates • In the Small Intestine - broken down to simple sugars and then absorbed! • Absorption primarily done through a co-transport system • Glucose is taken into intestinal epithelium with sodiumions (Na+) and released when sodium ions are pumped out of the cell • Transported to Liver • Release into blood stream • Converted into glycogen • Converted into fat

  39. Functions of Glucose and Sugars • Energy • Building blocks for other cell components • Spares protein from being used as energy source • Prevents ketosis • Cell surface markers and receptors

  40. Lactose Intolerance Consequence of lactase deficiency, and the inability of adults to digest lactose no enzyme to break glucose-galactose bond. May be genetic or environmental Symptoms: after consuming significant amounts of lactose. abdominal bloating, cramps, flatulence diarrhea nausea, borborygmi vomiting Lactase activity is high in newborns, but declines after weaning. Most can handle ½ to 1 cup of milk with a meal; lactose containing foods with more fat meal helps reduce discomfort

  41. Regulation of Blood Glucose • Normal BG is 70-100 mg/dl • After a meal, insulin levels rise which helps to store away glucose into tissues • If fasting glucagon levels rise, mobilizing glucose from storage into the blood • Epinephrine and NE both are released during sympathetic NS activation, mobilizing glucose into the blood • Cortisol and Growth Hormone decrease glucose use by muscle, but increase blood glucose

  42. When blood Glucose is high Insulin is released to make blood Glucose lower (normal) Cells in your body up-take the glucose

  43. When blood Glucose is low Glucagon is released to make blood Glucose higher (normal) Liver is a key site: Hepatocytes liberate Glucose stores (glycogen) and use fats & proteins to make more glucose Glycogenolysis *

  44. Regulation of Blood Glucose • Hyperglycemia(fasting 126 mg/dl) • Hypoglycemia(fasting below 50 mg/dl) symptoms: • irritability, sweating, anxiety, weakness, headache, confusion • Reactive hypo- due to exaggerated insulin response after eating • Fasting hypo- low BG after fasting for 8+ hours

  45. Comparison of Molecules (120 Kcal each) Sucrose Ethanol Glucose 1 glass of orange juice. 2 slices of bread. 1 shot of bourbon.

  46. Sucrose Ethanol Glucose 1 glass of orange juice 2 slices of bread 1 shot of bourbon 60 kcal glucose + 60 kcal fructose Starch => glucose CNS Depressant ~24 kcal used by all cells in body ~48 kcal used by all cells in body ~96 kcal used by all cells in body ~96 kcal hits Liver for Metabolism ~24 kcal hits Liver for Metabolism ~72 kcal hits Liver for Metabolism Glucose-6-℗ Glucose-6-℗ ↑ Aldehydes ↑ Acetate ↑ Citrate ↑ VLDL ↑ Aldehydes ↑ Uric acid ↑ VLDL + ↓NO = ↑BP Makes Glycogen ~0.5 kcal used for de novo Lipogenesis ↑ de novo Lipogenesis ↑ de novo Lipogenesis ↑ Insulin Dislipidemia Inhibits Ghrelin No effect on Ghrelin ↑Insulin resistance

  47. Metabolic Syndrome Is a state of numerous metabolic factors existing in one individual which include: • High Blood Pressure • Abdominal Fat • High Blood Triglyceride levels • High Uric Acid levels • Insulin Resistance • State of Chronic Inflammation Risks = Cardiovascular Disease and Diabetes Mellitus Type II . * Est. over 50 million Americans have this condition. * Hypothesized link to over consumption of high-fructose corn syrup (HFCS) and metabolic syndrome.

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