Nutrition Exam 2

Acetyl CoA

When oxygen is present, aerobic metabolism can proceed. Formation of acetyl coenzyme is a transition step that prepares pyruvate for entrance into the citric acid cycle. The remaining two-carbon compound combine with a molecule of coenzyme A to form acetyl-CoA. High-energy electrons are release and passed to NAD to form NADH, which transports them to the last stage of cellular respiration. Acetyl-CoA then enters the third stage of breakdown: the citric acid cycle.

Ketones/ Ketosis

Molecules formed in the liver when there is not sufficient carbohydrates to completely metabolize the two-carbon units produced from fat breakdown. To spare protein, after three days of fasting, the brain begins to obtain about half of its energy from molecules ( ketones). Smaller molecules than fatty acids, cross into the brain and be used for energy. Formed in moderate amounts during sleep. Circulate in the blood and can be used by muscle, heart , and other tissues.

Foods with high quality protein and low quality. Cheese and eggs?

- Animal proteins. - Plant proteins. - Yes, animal based proteins.

ATP

Adenosine Triphosphate: Consists of an adenosine molecule attached to three phosphate groups. The bonds between the phosphate groups are very high in energy, which is release when the bonds are broken. Captures and transfers release energy in all plants and animals. More bonds, more energy. Build it, capture, release. Flexible molecule transferring energy. Center of energy transfer. Build & Break. Not perfect. Lose= 50%

Omega 3 VS. Omega 6 fatty acids

Omega 3: Linoleic acid is an omega 3 fatty acid that is found in nuts, flaxseed, and canola oil. Eicosapentaenoic acid (EPA) and docosahexaenoic acid are omega 3 fatty acids that are synthesized from linoleic acid. Found n fatty fish. Both are needed for heath, essential for growth, development, fertility, and maintaining the structure of red blood cells and cells in the skin and nervous system. Omega 6: Linoleic acid is an omega-6 fatty acid that is found in vegetable oils, such as corn and safflower oils. Arachidonic acid is an omega-6 fatty acid synthesized from linoleic acid; it is found in both animal and vegetable fats. Omega-3 fatty acid DHA is important in the retina of the eye. Both DHA and the omega-6 fatty acid arachidonic acid are needed to synthesize cell membranes in the central nervous system and are therefor important for normal brain development in infants and young children.

Protein-energy malnutrition, kwashiorkor and marasmus? Common in US? World?

PEM: A condition characterized by loss of muscle and fat mass and an increased susceptibility to infection that results from the long-term consumption of insufficient amounts of energy and/or protein to meet the body's needs. -Kwashiorkor: Kcalories "okay", protein- adequate. A form of protein-energy malnutrition in which only protein is deficient. -Marasmus: Kcalores: inadequate, protein also inadequate. A form of protein-energy malnutrition in which a deficiency of energy in the diet causes severe body wasting.

Saturated VS Unsaturated

Saturated: A fatty acid in which the carbon atoms are bonded to as many hydrogen atoms as possible; it therefore contains no carbon-carbon double bonds. Unsaturated: A fatty acid that contains one or more carbon-carbon double bonds; may be either monounsaturated or polyunsaturated. Unsaturated fats have bent chains. This makes triglycerides that are higher in unsaturated fatty acids. Saturated fatty acids are more plentiful in animal foods, meat dairy

Rich food sources of saturated, monounsaturated, and polyunsaturated fatty acids

Saturated: Red meat, cheese, and whole milk. Monounsaturated: Canola oil, peanut oils, nuts and avocadoes, olive oil. Polyunsaturated: Corn oil, safflower oil, soybean oil, and nuts. Soybean: When stored at room temp. in loosely capped containers, would turn rancid in the shortest time

Gluconeogenesis

The synthesis of glucose from simple noncarbohydrate molecules. Amino acids from protein are the primary source of carbons for glucose synthesis. When glucose is not being supplied by the diet, it can come from the breakdown of glycogen as well as from synthesis. Occurs in liver and kidney cells, is an energy-requiring process that synthesizes glucose from three-carbon molecules. Essential for meeting the body's immediate need for glucose when energy and/ or carbohydrate intake is very low.

Sterol Vs. Phospholipid VS Triglyeride

Triglycerides: The major type of lipid in food and the body, consisting of three fatty acids attached to a glycerol molecule. Make up most of the lipids in our food in our bodies. Contain any combination of fatty acids. The fatty acids in a triglyceride determine its function in the body and the properties it gives to food. Phospholipids: Act as emulsifiers because they can surround droplets of oil, allowing them to remain suspended in a watery environment. Important component of cell membranes. They for ma double-layered sheet called the lipid bilayer. They allow water and fat to mix. 3 carbon backbone, 2 fatty acids, phosphorous section. Sterol: A type of lipid whose structure composed of multiple chemical rings. Present in small amounts similar to phospholipids. Functional molecules, does not need energy.

how is the body able to store excess carb, protein, and fat in adipose cells?

- After a meal, digested the resulting glucose, fatty acids, are absorbed. The remains can be converted into storage molecules. Carb: Stimulates anabolic pathways. - Fat: Excess energy consumed as fat is packed in chylomicrons and transported directly from the intestines to the adipose tissue. - Protein: ?

Cis fatty acids VS Trans fatty acids

Cis fatty acids: In cis fatty acids the hydrogen's are on the same side of the double bond and cause a bend in the carbon chain. Trans fatty acids: The hydrogen's are on opposite sides of the double bond, making the carbon chain straighter, similar to the shape of a saturated fatty acid. Difference: The orientation of hydrogen atoms around the carbon-carbon double bond distinguishes cis fatty acids from trans fatty acids. Most unsaturated fatty acids found in nature have double bonds in the cis configuration.

Pos. of alcohol

-Can stimulate appetite, improve mood, and enhance social interactions. Lowers cardiovascular risk by raising blood levels of HDL cholesterol and by inhibiting the formation of blood clots Reduce risk of death young middle-aged and older adults.

Quality of protein? limiting amino acid? Non-essential amino acid missing?

- A measure of how good the protein in a food is at providing the essential amino acids the body needs to synthesize proteins. - Limiting amino acids: The essential amino acid that is available in the lowest concentration relative to the body's need. - Under certain conditions, certain nonessential amino acids cannot be synthesized in sufficient amounts to meet the body's need. These are referred to as conditionally essential amino acids. - The body cannot make new proteins without breaking down existing proteins to provide the need amino acids.

Three basic processes of energy metabolism

- Energy yielding nutrients conversion to Acetyl CoA - Acetyl CoA goes through TCA cycle - Electron transport system.

Factors that influence rate of absorption and metabolism of alcohol

- How empty your stomach is, Kind and quantity of alcoholic beverage consumed, the speed at which the beverage is consumed, the food consumed with it, the weight and gender of the consumer, and the activity of alcohol-metabolizing enzymes in the body.

What causes Urine and breath to smell slightly sweet, sort of like acetone, in individuals with untreated diabetes? Could this happen during starvation?

- Ketosis. Mild ketosis can happen during starvation or when consuming a low-carb weigh-loss diet and can cause symptoms. - Diabetes: Does increase heart disease risk.

If matt continued on the starvation diet, what metabolic changes would occur?

- Large amounts of body protein will need to be broken down to supply it. Gluconeogenesis provides glucose by synthesizing it from the three-carbon molecules derived primarily from amino acids. Compounds that contain two carbons, such as acetyl-CoA derived from fatty acid breakdown, cannot be used to make glucose, and the liver converts them to ketones.

Basic structure of amino acid. Differences, how many?

-20 amino acids found in proteins -9 essential -11 nonessential Peptide bond → Polypepticle. -The side chains of amino acids vary in size and structure

Neg- Long term effects of alcohol

-Alcoholism: Addiction to alcohol. Liver disease, malnutrition, deficiency of B vitamins, cancer of oral cavity, pharynx, esophagus, larynx, breast, liver, colon, rectum, and stomach.

Differences and similarities of chylomicrons, VLDL, HDL, LDL

-Chylomicrons: A lipoprotein that transports lipids from the mucosal cells of the small intestine and delivers triglycerides to other body cells. The largest lipoproteins and contain the greatest proportion of triglycerides. -VLDL: Are smaller than chylomicrons but still contain a high proportion of triglycerides. -LDL: Contain a higher proportion of cholesterol than do other lipoproteins. -HDL: High in cholesterol and are the densest lipoproteins due to their high protein content.

End products of Energy metabolism

-Co2, H2O, ATP (energy).

Required for protein intake? DNA, mRAND, transfer RDA, and ribosomes

-DNA, m-RNA, Ribosome site protein production, tRNA. -DNA: Blueprinte for protein -mRNA: Copy portion of DNA messenger RNA Ribosomes: Site protein production

Deamination and denaturation

-Denaturation: Alteration of protein's three-dimensional structure. Loss of 3 structures, food. -Deamination: The removal of the amino group NH2. Used to produce ATP. Clip of nitrogen. The removal of the amino group from an amino acid.

Differentiate essential and nonessential amino acids. How many. Are both in our food?

-Essential: An amino acid that cannot be synthesized by the body in sufficient amounts to meet its needs and therefore must be included in the diet. 9 essential -Nonessential: The other 11 amino acids, or dispensable, they can be made in the body. - Yes.

Why does fat provide more energy than carb, protein, and alcohol?

-Fat is an efficient way to store energy because each gram of fat provides 9 calories, compared to 4 calories.

Generic lipoprotein. Why not in foods?

-Generic lipoprotein: A particle that transports lipids in the blood. Covered with a water-soluble envelope of protein, phospholipids, and cholesterol to form particles. -Only present on the surface of cells lining the blood vessels.

How many carbons?

-Glucose: 6 -Glycerol: 6 -Fatty acids: ? -Alcohol: 2 -Pyruvate: 3 -Acetyl CoA: 6

Some amino acids are glycogenic? When is it important for glycogenic amino acids to be metabolized to glucose?

-Glycogenic: When energy is deficient, body proteins such as amino acids, form pyruvate or intermediates in the citric acid cycle which can then be used to make glucose.

Progression in an artery to atherosclerosis

-Healthy artery: The wall of a normal healthy artery is lined with epithelial cells surrounded by smooth muscle. -Damage to the Artery Wall: Causes inflammation and begins process of plaque formation. Attracts white blood cells, mature into macrophages, makes the lining more permeable to LDL particles. LDL is oxidized to form oxidized LDL cholesterol - Plaque Formation: Plaque builds up, causes artery to narrow and lose its elasticity. Cells smooth form over the plaque alling it off from the lumen of the artery. -Plaque Rupture: Inflammation continues, fibrous cap covering the plaque degrades, ruptures erodes, blood clots. Can block an artery. -Heart Attack: Blood flow is blocked.

Hydrogenation

-Hydrogenation: Break double bond, add hydrogen. A process whereby hydrogen atoms are added to the carbon-carbon double bonds of unsaturated fatty acids, making them more saturated. -Manufacturers used this because: It increases the shelf life of oils; it improves the storage properties of the oils and makes them more solid at room temperature. -Neg: Increase amount of saturated fat, produced trans fatty acids. Transforms cis to the trans configuration.

Neg. Short term effects of alcohol

-Impairing mental and physical abilities, reasoning, vision, speech, and muscle control. Alcohol poisoning: Slow breathing, heart rate, and gag reflex. Amnesia, Blackout drinking.

Lacto-ovo Vegetarian? Vegan?

-Lacto-ovo vegetarian: Vegetarian, Excludes all flesh of animals, can have diary. Eggs, dairy, milk, and cheese. -Vegan: Excludes all food of animal origin. Pos: Lower sat fat, more fiber, more antioxidants, lower obesity, lower calorie intake, lower in blood pressure, lower in cardio vascular, lower in cancer.

Alcohol Deydrogenase, MEOS

-MEOS: Microsomal ethanol-oxidizing system metabolizes alcohol. Activity increases when more alcohol is consumed. Metabolizes other drugs. Alcohol Dehydrogenase: Are a group of dehydrogenase enzymes that occur in many organisms and facilitate the interconversion between alcohols and aldehydes or ketones. In people who occasionally consume moderate amounts of alcohol most of the alcohol is broken down in the liver by the enzyme alcohol dehydrogenase.

Nitrogen Balance. Neg? Zero? Pos? Can people force balance by taking in amino acid supplements?

-Nitrogen balance: The amount of nitrogen consumed in the diet compared with the amount excreted over a given period. -Neg: Nitrogen input < Nitrogen output. This indicates that more protein is being broken down than is being synthesized so body protein is decreasing. Occurs due to injury of illness as well as when the diet is too low in protein or calories. -Zero: Nitrogen intake= Nitrogen output: This indicates that the amount of protein being synthesized is equal to the amount being broken down, so the total amount of protein in he body is not changing. Healthy adults who consume adequate amounts of protein are in nitrogen balance. -Pos: Nitrogen intake> Nitrogen output: This indicates that there is more protein synthesis than degradation so the body is gaining protein. This occurs when the body is growing, during pregnancy, and in individuals who are increasing their muscle mass by lifting weights. - Protein and amino acid supplements are rarely needed to meet protein needs. Supplements are marketed to boot total protein intake, to add individual amino acids, and to provide enzyme activity

Oil, margarine, butter. Does corn oil have sautéed fats? Compare.

-Oil: Phospholipid, High in Omega-3 fatty acids, reduce the risk of heart disease and decrease mortality. -Margarine: Used in cooking or added at the table are the most concentrated sources of fat in the diet. Corn oil: Butter kcalories, Margarine: 9kcalories 20-35% fat intake. Butter has the most saturated fat Most trans fat: Oil. The fat in butter does not have more kcalories per gram than fat in oils.

Major roles of protein in the body

-Provides structure and regulation, source of energy, growth build tissue, hormones, enzymes, fluid balance between cells, acid-base regulator, transporter, and immune system-antibodies.

Deamination? What happens to the ammonia and urea?

-The amino group NH2 must be removed. -Changes Urea into Urine.

Protein in egg when cooked? Does lower the quality of protein?

-The heat denatures the protein. The protein in raw egg white forms a clear, viscous liquid, but when cooing denatures it, the egg white becomes white and firm and cannot be restored to its original form. No it does not.

Is cholesterol essential?

-Yes, The body requires from the diet a small portion to be fats, otherwise, be very high in carbohydrate which would not be very palatable and would not mean healthier than diets with fat.

Digestion, absorption, metabolism of alcohol

1. ADH breaks down alcohol to produce acetaldehyde. 2. Acetaldehyde is toxic and is degraded to produce acetyl-CoA 3. The breakdown of alcohol and acetaldehyde releases electrons that can be used to produce ATP and also results in changes that inhibit the citric acid cycle, limiting breakdown of acetyl-CoA. 4. Acetyl-CoA that cannot enter the citric acid cycle is used to synthesize fatty acids, which accumulate in the liver. 5. When larger amounts of alcohol are consumed, MEOS activity increase. The MEOS also converts alcohol into acetaldehyde, which is then broken down to form acetyl-CoA.

Major risk factors for coronary heart disease. Changes?

1. High blood cholesterol 2. Diabetes 3. Cigarette smoking 4. Hypertension 5. Family History 6. Age -Lower sodium intake, reduce saturated fats in diet, Limit some foods, lower dietary Chol < 200mg/d, Lower salt intake, increase others: Higher MUFA up to 20%, Higher fiber 25-30 g/day, higher high fat

Protein digestion and absorption

1. Mouth: chewing tears into smaller pieces. No chemical 2. Stomach: HCI denatures protein. Proteases breaks large proteins into small molecules. 3. Pancreas: Secreted into SI 4. SIntestine: Pancreatic & intestinal enzyme breakdown to amino acids. Absorbed into vascular system directly to liver. - Complementary protein nutrition: A strategy that combines plant proteins in the same day to improve the balance of essential amino acids. - Protein utilization: Nitrogen Balance.

Triglycerides and fatty acids

A triglyceride consists of the three-carbon molecule glycerol with three fatty acids attached to it. A fatty acid is a chain of carbon atoms with an acid group at one end of the chain. Triglycerides/ fatty acids: Basic structure: Packaging of fatty acids. Chain length. Composed of 2-carbon skeleton molecules

Glycolysis

Also called anaerobic metabolism. Metabolic reactions in the cytosol of the cell that split glucose into two 3-carbon pyruvate molecules, yielding two ATP molecules. First stage of cellular respiration takes place in the cytosol of the cell or glycolysis. " Glucose breakdown". The 6-carbon sugar glucose is broken into two 3-carbon pyruvate molecules. These reactions generate two molecules of ATP for each molecule of glucose and release hydrogen ions and high-energy electrons that are passed to NAD. The conversion of glucose to pyruvate.

Lactic acid

An end product of anaerobic metabolism and an additive used in food to maintain acidity or form curds.

Cellular oxidation of carb

End products: Water and carbon dioxide

Anabolism

Energy-requiring processes in which simpler molecules are combined to form more complex substances. Metabolic reactions that combine simple molecules to form the body's complex structural and functional components. When tow or more atoms, ions, molecules combine to form new and larger molecules. Glucose, fatty acids, and amino acids that are not broken down for energy are used in anabolic pathways to synthesize structural, regulatory, or storage molecules. Endergonic: They consume more energy than they produce. They require ATP as a source of energy.

Ketosis

High levels of Ketones in the blood

Pyruvate

Intermediates in the citric acid cycle, which can then be used to make glucose. Produce of glucose in the citric acid cycle. 3 carbons

Electron transport chain

Last stage of cellular respiration. In citric acid cycle, high-energy electrons from the breakdown of amino acids are transferred to the electron transport chain where the energy is trapped and used to produce ATP and water.

Linolenic VS Linoleic

Linolenic: (Omega-6) Found in vegetable oils, such as corn and safflower oils. Linoleic: (Omege-3) Found in nuts, flaxseed and canola oil.

Enzymes

Protein molecules that accelerate the rate of specific chemical reactions without being changed themselves. Chemical reactions of metabolism are facilitated by enzymes. Most require the assistance of helper molecules called cofactors. When energy is deficient, body proteins such as enzymes and muscle proteins are broken down into amino acids. Protein is the structure of an enzyme.

Catabolism

The processes by which substances are broken down into simpler molecules releasing energy. Metabolism refers to all of the chemical reactions and metabolic pathways that occur in the body, some of these reactions break down complex organic molecules into simpler ones. Known as catabolism. Split up large molecules, atoms, or ions. Exergonic: They produce more energy than they consume, releasing the chemical energy stored in the bonds that hold molecules together.

Metabolism

The sum of all the chemical reactions that take place in a living organism