NHM 101 1nd Edition Exam 4 Study Guide Outline of Last Lecture I. Lifestyle Nutrition Outline of Current Lecture II. Study Guide for final examCurrent LectureSix Classes of Nutrients- Carbohydrates - Proteins- Lipids- Vitamins- Minerals - WaterWhich nutrients provide energy- Carbohydrates- Lipids- Proteins Any nutrition calculations that we have covered in class. Go back over the nutrition calculations assignment for practice. Dietary Reference Intakes including UL, RDA, and AI- UL highest level of daily nutrient intake that is unlikely to have adverse health effects - RDA amount of nutrients needed to meet requirements of almost all healthy individuals- AI nutrient recommendation based on observed or experimentally determined appromimation Best Source of Nutrition Information- Qualified nutrition professionals- Some physicians - Registered dietitians These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.Dietary Guidelines- Reviewed every five years - USDA and HHS jointly create each edition MyPlate- Current food icon- We are consuming too many foods high in fat and added sugars- Too few veggies, fruits, whole grains and milk products Food Groups- Fruits- Vegetables- Grains- Protein foods- Milk and milk products Nutrition Facts Labels and Nutrition Claims on Labels- Fat-free less than .5 gm of fat per serving- Low fat less than 3gm of fat per serving- Trans fat-free less than .5 gm of trans fat and less than .5g of saturated fat per serving - Light or lite1/3 fewer calories than the comparison food - Organic at least 95% of products ingredients have been grown and processed according to USDA regulations Anatomy of Digestive Tract- Mouth- Esophagus- Stomach- Small intestine - Large intestine - Rectum - Anus Movement of Food through the Digestive Tract (peristalsis, sphincters)- Mouth esophagus stomach small intestine large intestine rectum  anus- Peristalsis wavelike muscular contractions of the GI tract that push the contents - Sphincter circular muscle surrounding, and able to close, a body opening o Keeps the flow of food in one direction Absorption- Most absorption occurs in the small intestine- Fibers are not absorbed and continue through the digestive tract Structure and Characteristics of Lipids, Proteins, and Carbohydrates- CHOo Monosaccharides  Single sugars  Simple o Disaccharides Pairs of mono Simpleo Polysaccharides Large  Chains of mono Complex- Lipidso Tyiglycerides o Phospholipidso Sterols - Proteinso Proteins are made up of amino acidso Amino acids contain nitrogen (N), carbon (C), hydrogeno (H), and oxygen (O).o All amino acids have the same basic structure.o Central carbon atomo Hydrogen atomo Acid group (COOH)o Amino Group (NH2)o Side group varies with each amino acidFunctions of the Macronutrients- CHOo Glycogen is the primary source of energy for cells - Lipids o Part of every cell membraneo Energyo Insulation of body tempo Protection to vital organs- Proteins o Structuralo Enzymeso Hormones o Regulators of fluid balanceo Acid-case regulators o Transporterso Antibodies o Source of energy and glucose Digestion process of each macronutrient- CHO o DIGESTION o Moutho Salivary enzyme amylase hydrolyzes starch into smallero molecules (shorter polysaccharides or maltose)o Stomacho No new enzymes are introduced to break down CHOo Salivary amylase diminishes as stomach acid and proteindigestingo enzymes break it downo Fiber may promote satietyo Small Intestineo Pancreatic amylase continues breaking down polysaccharideso Final digestion takes place on outer membranes of intestinalo cellso Maltaseo Breaks maltose into 2 glucose moleculeso Sucraseo Breaks sucrose into glucose and fructoseo Lactaseo Breaks lactose into glucose and galactoseo Mostly glucose molecules remaino Large Intestineo Fibers remain and attract watero Bacteria in GI tract ferment some fibers (mainly soluble)o Generates water and gaso Fibers do contribute a small amount of energy for the colon (~2kcal/g)o ABSORPTIONo Primarily takes place in the small intestineo Active transporto Glucose and galactoseo Facilitated diffusiono Fructoseo Fructose and galactose are metabolized by the livero Glucose sent to body’s cells for energy- Lipidso DIGESTIONo Challenge is to keep the lipids mixed vs. separationo Lipids hydrophobico Digestive enzymes are hydrophilico Moutho Some hard fats melto Stomacho Muscles contract to propel contents toward pyloric sphinctero Lipid particles broken down by gastric lipaseo Small Intestineo When fat enters, cholecystokinin (CCK) is released whicho signals the release of bile from the gallbladdero Bile acts as an emulsifier so the enzymes can act on the fato Most fat digestion occurs in the small intestineo Pancreatic lipases and intestinal lipaseso ABSORPTIONo Glycerol and short- and medium-chain fatty acidso absorbed directly into the bloodstreamo Monoglycerides and long-chain fatty acids formo micelles (spherical complex)o Transported by proteins called chylomicronso Lipid transport is made possible by a group of vehicleso known as lipoproteinso Chylomicronso Largest of the lipoproteinso Least denseo Get smaller as triglycerides are removed by the cellso Very-Low-Density Lipoproteins (VLDL)o Composed primarily of triglycerideso Transport lipids to the tissueso Get smaller and more dense as triglycerides are removed and VLDLo becomes an LDLo Low-Density Lipoproteins (LDL)o Composed primarily of cholesterol with few triglycerideso Transport lipids to the tissueso High-Density Lipoprotein (HDL)o Composed primarily of proteino Transport cholesterol from the cells to the livero Health Implicationso High LDL is associated with higher risk of heart disease ando known as “bad” cholesterolo High HDL appears to have a protective effect- Proteino DIGESTIONo Moutho Proteins are crushed and moistenedo Stomacho Partial breakdown of protein through hydrolysiso Hydrochloric acid uncoils (denatures) proteinso Small Intestineo Polypeptides enter the SIo Pancreatic and intestinal proteases hydrolyze them into smallero peptide chains and single amino acidso Peptidases on the intestinal wall split most