HNTR 1153 Complete Exam 2025

How are fats important in the body and in foods? - - - Energy fuel - Energy stores - Emergency reserve - Padding - Insulation - Cell membranes - Raw materials - Nutrients - Transport - Energy - Sensory appeal - Stimulate the appetite - Texture - Satiety Which is the predominant class of fat in our foods and bodies? - -Triglycerides - 95% In which class is cholesterol found? - -Sterols What is the primary role of phospholipids? - -- Forms the membranes of the cells - Serves as an emulsifier Saturated fat - -- Triglycerides in which most of the fatty acids are saturated - Carries the maximum number of hydrogen atoms (no points of saturated) - Contains three saturated fatty acids Trans fat - -- Fats that contain any number of unusual fatty acids formed during processing - Form during hydrogenation - polyunsaturated fats are hardened and some of the unsaturated fatty acids change shapes instead of become saturated - Similar in shape to saturated fatty acids Health effects of trans fats - -- Risk to heart and arteries because it raises LDL cholesterol, worsens atherosclerosis causing cell toxicity and increasing inflammation - Risk is similar or slightly higher than saturated fats - They should be avoided as much as possible Monosaturated fat - -Triglycerides in which most of the fatty acids have one point if unsaturation HNTR1153 HNTR1153 Polyunsaturated fat - -Triglycerides in which most of the fatty acids have two or more points of unsaturated Which types of fats are solid at room temperature? - -- Saturated fats - The more unsaturated it is, the more liquid it will be at room temp Lipid digestion and absorption - -- Mouth and stomach = little fat digestion - Small intestine = most of fat digestion accomplished by digestive enzymes, bile which emulsifies fat, and enzymes that cleave triglycerides into free fatty acids, glycerol, and monoglycerides - Intestinal lining = parts absorbed by the intestinal villi - Glycerol and short-chain fatty acids enter directly into the blood stream - The cells of the intestinal lining convert large lipid fragments, such as monoglycerides and long-chain fatty acids, back into triglycerides and combine them with protein forming chylomicrons that travel in lymph vessels to the bloodstream DRI recommendation for cholesterol - -Less than 300mg/day DRI recommendation for total fat - -20-35% of daily energy from total fat DRI recommendation for saturated fat - -Less than 10% from saturated dat DRI recommendation for trans fat - -As little as possible Daily intake recommendation for EPA and DHA - -- No DRI recommendation - Average of 250mg/day Low-density lipoproteins - -- Transport cholesterol and other lipids to the tissues from the liver for their use - Made from very low-density lipoproteins after they have donated many of their triglycerides to body cells High-density lipoproteins - -Lipoproteins that return cholesterol from the tissues to the liver for dismantling and disposal; contain a large proportion of protein Desirable blood lipid value of cholesterol - -200mg Desirable blood lipid value of LDL - -100 mg Desirable blood lipid value of HDL - -60 mg Desirable blood lipid value of triglycerides - -150 mg Name the two main dietary factors associated with an increase in blood cholesterol, contributing to the risk for heart disease. - -High saturated fat intake and high trans fat intake HNTR1153 HNTR1153 Identify the two essential fatty acids - -- Linoleic acid (omega-6) - Linolenic acid (omega-3) What are the characteristics of essential fatty acids? - -- They must be supplied by the diet AND very little fat is needed in the diet to prevent a deficiency - Polyunsaturated fatty acid with its endmost double bond 6 or 3 carbons from the end of the carbon chain What are good food sources of linoleic acid (omega-6) - -- Vegetable oils (corn, cottonseed, safflower, sesame, soybean, sunflower) - Margarines made from nut and seed oils (cashews, walnuts, sunflower) What are good food sources of linolenic acid (omega-3)? - -- Vegetable oils (canola, flaxseed, soybean, walnut, wheat germ) - Margarine made from canola or soybean oil, nuts, and seeds (chia seeds, flaxseeds, walnuts, soybeans) - Soybeans What are good food sources for EPA and DHA? - -- Human milk - Fish and seafood Why are the omega 3 fatty acids, EPA and DHA, so important? - -- Heart health: regulate heartbeats, regulate blood pressure, reduce blood clot formation, reduce blood triglycerides, stabilize plaque in arteries, and reduce inflammation; linked with fewer heart attacks and strokes - Cancer prevention: possible because they suppress inflammation - but there is no strong link for this, some studies have shown higher risks of cancer actually - Cell membranes: promote healthy tissue function - Brain function and vision: assist in the brain's communication processes and reduce inflammation associated with aging Are all food products that claim to be good sources of omega 3 fatty acids also good sources of EPA and DHA? - -Not necessarily - the most popular fish eaten in the USA are low in EPA and DHA What should you look for on the ingredient list to choose a heart healthy margarine? - Made from vegetable oils that contain unsaturated good fats like polyunsaturated and monosaturated fats What factors characterize the 'Mediterranean Diet'? - -- Little saturated fats and high in monounsaturated fat and dietary fiber - Ample vitamins, minerals, fibers, phytochemicals Proteins are composed of long strands of ______ and linked together by ______ - -- Amino acids HNTR1153 HNTR1153 - Peptide bonds Amino acids contain ______ - -Nitrogen - a key difference that distinguishes protein from carbohydrate and fat The order of amino acids in a protein is based on a person's __________ - -genetic code Each of the twenty amino acids in the human body has a unique side chain, which gives the completed protein its _______ - -unique shape and function The nitrogen containing part of an amino acid is called the _______ - -amine group What happens if amino acids are oversupplied? - -- The amine group is removed and converted to ammonia in the liver - The remaining carbon backbone is converted to glycogen or fat. Where does protein digestion begin - -In the stomach - hydrochloric acid denatures the protein strands and an enzyme cleaves amino acid strands into polypeptides and a few amino acids Which organ is primarily responsible for secreting enzymes for protein digestion? - Pancreas What is the acceptable intake range for protein? - -10 to 30 percent of calories or 0.8 grams of protein per kilogram of body weight How to calculate the protein needs of a person weight 132 pounds - -- First divide weight in pounds by 2.2: 132 ÷ 2.2 = 60 kilograms (kg). - Next multiply weight in kilograms by 0.8: 60 kg x 0.8 grams protein = 48 grams protein required daily Define nitrogen balance - -The amount of nitrogen consumed compared with the amount exerted in a given time period Nitrogen equilibrium - -- Nitrogen in = nitrogen out - Same amount of protein in their bodies at all times - Should be like this for healthy people Positive nitrogen balance - -- Nitrogen in exceeds nitrogen out - More proteins are being build than are being broken down and lost - Growing children have a positive nitrogen balance because they have to add new blood, bone, and muscle to their bodies - Pregnant women also have a positive nitrogen balance Negative nitrogen balance - -- Nitrogen out exceeds nitrogen in HNTR1153 HNTR1153 - Muscle or protein tissues are broken down and lost - Triggered by illness or injury when the body breaks down less vital proteins such as those of the blood, skin, and muscle - this floods the body with amino acids which are stripped of their nitrogen and used for energy to fuel the body's defense - Astronauts experience this because their muscles waste and weaken What type of proteins provide all the essential amino acids? - -Complete proteins, aka high quality proteins Where are complete proteins found? - -- Animal sources (milk, eggs, cheese, meat, fish, poultry) - Soy or soybean products Incomplete proteins, aka low quality proteins - -- Missing one or more essential amino acids - Found in grains, vegetables, and all legumes except soy What concept might vegetarians use to combine foods in order to obtain suffi