Notes 04 03 2014 09 54 00 Nutrition and Digestion not all people need supplements such as calcium vitamin d b 12 saturated fats are TO BE AVOIDED FOOD PYRAMID Nutrition consume and assimilate chemicals nutrients for 1 Growth 2 Energy 3 Body maintenance we don t use elements chemical components directly WE DON T USE THINGS DIRECTLY don t eat a steak and get muscle Salts water small molecules can pass THROUGH the wall of digestive right away It breaks down then goes back and builds muscle tract directly used Large molecules polymers are DIGESTED to simple compounds BROKEN DOWN to pass through the digestive tract wall before they are used for body building or energy Can t assimilate polymers DIRECTLY complex carbs proteins fats Can t be digested at all Passes through without contributing to your body energy assembly Ex cellulose has no nutritional value and 0 calories structure of chains iMPORTANT because flexibility is different so more flexible healthier cells Carbohydrates energy is the material used to move grow things different FORMS of energy all reactions cost some amount of energy 1 Plant gets it from sun 2 We get it from potato ALL ENERGY FROM THE SUN direct not photosynthesis plants take in solar energy and use it to make chemicals that contain energy take co2 water carbs like starch cellulose converts and stores light energy as chemical bond energy digesting polymers releases small molecules sugars that can be used for growth movement re assimilated and stored as a polymer Fats by animals seeds too have chemical energy energy is transferred by plant animals EAT THAT ENERGY by eating the plant most efficient transfer of solar energy noms humans get energy by digesting polymers which release energy doing that so we take the released energy Chemical Makeup glucose c 6 h 12 o 6 glucoses joined together complex carbohydrates starch can be digested so has calories cellulose not digested zero calories and sold as fiber But has a lot of energy but we can t USE that because we can t break it down Fat digestion fats digested to release fatty acids that are needed to make the hydrophobic interior of cell membranes that separate hydrophilic inside from saturated fatty acids straight structure hch structure filled with hydrophilic outside passes through phobic parts the h vs unsaturated fatty acids ch structure bent harder to stack polar head and non polar tails unsaturated bonds MORE FLEXIBLE and more flexible membranes flexibility decreases hardens membranes when you have saturated facts cholesterol insertion phobic b c fatty acids reduces flexibility hardens it Fats omega 6 and omega 3 trans fat omega 3 and 6 natural saturated natural unsaturated mono vs ply unsatur Poly has Poly unsaturated fatty acids in fish canola oils lots of omega 3 6 transfats made by adding hydrogen items to solidify liquid oils natural version of an unsaturated fat is VERY flexible BUT if it has trans unsaturated fat transfat it is very UNFLEXIBLE why people make so much transfat add hydrogen content gets harder food processing production trans fat MAN MADE most cities have banned this in restaurants Most Saturated fat coconut oil most poly unsaturated safflower oil most mono unsaturated olive oil HDL proteins with small amounts of cholesterol good because removes cholesterol from walls and transports it to liver to take it from the LDL cholesterol with little protein bad because they deposit cholesterol on the walls of arteries Statin drugs inhibits human cholesterol biosynthesis want High density to be HIGH AND LOW TO BE LOW Elaboration on Women not relevant to nutrition phyto estrogens bind to estrogen receptor but are much weaker than estrogen and estrogen binding stimulates breast and uterine cell division but more cell divisions means MORE possibility of transforming into cancer cells body estrogen can effect increasing of cell divisions in a woman isoflavone competition can reducing estrogen can reduce cell division and when estrogen levels are low the isoflavone binding may substitute and reduce loss of estrogen effects like hot flashes Digestive Tract digestive wall 30 ft tube open at both ends with contents outside the body digestion reduces compounds in food to molecules that can pass through chewing reduces particle size and increases surface area for chemical enzyme digestion makes it small enough with some saliva to digest mouth chews it physical breakdown chemical stomach s hydrochloric acid chemical breakdown small intestine breaks it down with digestive enzymes digestive enzymes carbs broken down by amylases fats by lipases and proteins by proteases Stomach food and mouth 100 times more bacteria inside you than cells inside you stomach s acidic with a ph level below 2 so it kills most of the bacteria from stomach has gastric juice that begins protein digestion 1 muscles contract to mix contents and push towards small intestines stomach contents chyme 1 muscle contracts in wave pushing chyme onward 2 Layer contacts so there s space for it to move forward food enters small intestine stomach rumbling growling liquid air trapped heartburn too much acid in stomach so take alka seltzer tums alkali b c they neutralize stomach acid so work instantly non instant drugs zantac axid Pepcid because they shut down your acid production prevents heart burn sphincter anything that closes around the valve acid reflux disease stomach acid goes backwards up esophagus and burns lining small intestine first 12 18 inches is duodenum food enters and secretion from pancreas neutralizes and ph increases digestive enzymes from the liver collect in gall bladder and release into duodenum when food enters food exits stomach and immediately into the gull bladder collection sac and liver makes proteins needed to digest food remove gull bladder then you have to eat more often in smaller portions not serious BUT means lifestyle changes inside lining of intestine small covered by villi that increase surface area so maximizes surface area for digested products to pass through the walls each villa has a blood system and lymphatic system in it hepatic liver digestion products transferred from small intestine to liver through related to liver liver maintains glucose levels converts excess to glycogen and can reconvert that to glucose if hepatic portal vein needed liver can convert amino acids and fats to glucose if needed amino acids broken down releases amino groups and interacts with carbon dioxide urea pee Celiac Disease