HUN1201 FINAL EXAM

Organic

Contains carbon & hydrogen

Inorganic

Doesn't contain carbon or hydrogen

Macronutrients

Nutrients that the body requires in relatively large amounts to support normal function and health (carbs, proteins, lipids)

Micronutrients

Nutrients needed in relatively small amounts to support normal health and body functions (vitamins & minerals)

Fat-soluble vitamins

Vitamins that are not soluble in water but soluble in fat (A, D, E, K)

Water-soluble vitamins

Vitamins soluble in water (vitamin C & B-vitamins)

Kcal/g for carbs, proteins, fats, and alcohol

Carbs (4), proteins (4), fats (9), and alcohol (7)

Dietary Reference Intakes (DRIs)

A set of nutritional reference values for the United States and Canada that applies to healthy people

Estimated Average Requirement (EAR)

The average daily nutrient intake level estimated to meet the requirement of half of the healthy individuals in a particular life stage or gender group

Recommended Dietary Allowance (RDA)

The average daily nutrient intake level that meets the nutrient requirements of 97% to 98% of healthy individuals in a particular life stage or gender group

Adequate Intake (AI)

A recommended average daily nutrient intake level based on observed or experimentally determined estimates of nutrient intake by a group of healthy people

Tolerable Upper Intake Level (UL)

The highest average daily nutrient intake level likely to pose no risk of adverse health effects to almost all individuals in a particular life stage and gender group

Estimated Energy Requirement (EER)

The average dietary energy intake that is predicted to maintain energy balance in a healthy individual

Acceptable Macronutrient Distribution Range (AMDR)

A range of intakes for a particular energy source that is associated with reduced risk of chronic disease while providing adequate intakes of essential nutrients

Characteristics of a healthful diet

Adequate, moderate, balanced, varied

Nutrient density

The relative amount of nutrients per amount of energy (number of calories)

Chronic disease

A disease characterized by a gradual onset and long duration, with signs and symptoms that are difficult to interpret and that respond poorly to medical treatment

Determine Body Mass Index (BMI), measure body composition, and assess fat distribution patterns

How to evaluate if a person's body weight is healthful?

o Basal Metabolic Rate (BMR)

o Thermic Effect of Feeding (TEF)

o Thermic Effect of Activity (TEA)

What are the components of energy expenditure?

Anorexia nervosa

Self starvation leading to a severe nutrient deficiency

Bulimia nervosa

Recurrent episodes of extreme overeating and compensatory behaviors to prevent weight gain

Binge eating

Consuming large amounts of food in a short period of time without purging

Night-eating syndrome

People who were not hungry during the day, but eat in the evening and night

Reduced brain function and alcohol poisoning

What are the problems associated with alcohol abuse?

Small amount of alcohol is oxidized in the stomach, before being absorbed into the bloodstream. ADH reduces alcohol absorption. ADH is present in both the stomach and liver.

What are the steps in alcohol oxidation? What does ADH (alcohol dehydrogenase) do?

Moderate alcohol consumption

According to the Dietary Guidelines for Americans, moderate alcohol consumption is defined as having up to 1 drink per day for women and up to two drinks per day for men

Metabolic tolerance

A condition of cellular adaptation to a pharmacologically active substance so that increasingly larger doses are required to produce the same physiological or psychological effect obtained earlier with smaller doses.

Functional tolerance

A change in the post synaptic synapses of the CNS that occurs as a result from abnormal exposure to different exogenous and endogenous chemicals, particularly drugs (substances of abuse) and hormones

Hunger

A physiological drive for food that occurs when the body senses that we need to eat

Appetite

A psychological desire to consume specific foods

When we have not eaten for a while, our blood glucose levels fall, prompting a change in the levels of insulin and glucagon. This chemical message is relayed to the hypothalamus, which then prompts us to eat in order to supply our bodies with more glucose.

How do hormones regulate hunger?

o Stimulates secretion of pancreatic digestive enzymes

o Stimulates gallbladder contraction

o Slows gastric emptying

What does CCK (cholecystokinin) do?

o Gallbladder

o Pancreas

o Liver

Accessory organs of digestion

Absorption

The physiological process by which molecules of food are taken from the gastrointestinal tract into circulation

Digestion

The process by which foods are broken down into their component molecules, either mechanically or chemically

Elimination

The process by which the undigested portions of food and waste products are removed from the body

Segmentation

Rhythmic contraction of the circular muscles of the small intestine, which squeezes chyme, mixes it, and enhances the digestion and absorption of nutrients from the chyme

Passive diffusion

Nutrients move from high concentration to low concentration; no energy required

Facilitated diffusion

Nutrients move from high to low concentration with the help of a carrier protein; no energy required

Active transport

Nutrients move from low to high concentrations with the help of the carrier protein; energy is required

Endocytosis

A cell forms a vesicle to surround and engulf a nutrient and the nutrient is dissolved in water inside the vesicle, allowing whole proteins (like immunoglobulin from breast milk) to be absorbed intact

Carbohydrates (also called saccharides) are molecular compounds made from just three elements: carbon, hydrogen and oxygen. Monosaccharides (e.g. glucose) and disaccharides (e.g. sucrose) are relatively small molecules. They are often called sugars.

The small molecules that make up carbs are called ________.

Carbohydrate digestion begins in the mouth. The starch in the foods you eat mixes with your saliva during chewing. Saliva contains the enzyme salivary amylase, which breaks down starch into smaller particles and eventually in the disaccharide maltose. Carbohydrate digestion does not occur in the stomach because the acid in the stomach inactivates the salivary amylase enzyme. The majority of carbohydrate digestion occurs in the small intestine. The enzyme pancreatic amylase is secreted by the pancreas into the small intestine. Pancreatic amylase continues to digest any remaining starch into maltose. Additional enzymes found in the microvilli of the mucosal cells that line the intestinal tract work to break down disaccharides into monosaccharides.

Where does carbohydrate digestion occur, and what enzymes are involved?

A diet low in carbs

What kind of diet causes ketosis?

Hyperglycemia

A condition in which blood glucose levels are higher than normal

Hypoglycemia

A condition in which blood glucose levels are lower than normal

Insulin lowers blood glucose levels. Glucagon raises blood glucose levels.

What does insulin do? What does glucagon do?

Type 1diabetes is a disorder in which the pancreas cannot produce enough insulin. Type 2 diabetes is a progressive disorder in which body cells become less responsive to insulin.

What are the differences between type 1 and type 2 diabetes?

o Saturated - butter, cream, cheese, pork, lamb, fatty cuts of beef, salami

o Polyunsaturated - olive oil, peanut oil, corn oil, salmon, tuna, trout

o Monounsaturated - red meats, whole milk, nuts, high fat fruits such as olives and avocados

o Trans - baked goods, snacks, fried foods, creamer and margarine

Name some food sources of saturated fats, polyunsaturated fats, monounsaturated fats, and trans fat

Trans fats are more highly correlated with an increased risk for heart disease because they increase blood cholesterol levels by altering the way cholesterol is removed from the blood.

Trans fats are not good for health. Why not?

Omega-3 and omega-6 fatty acids

Name two essential fatty acids (EFAs)

Bile is a greenish fluid, produced by the liver that emulsifies the lipids/reduces lipids into smaller globules and disperses them so they are more accessible to digestive enzymes; secreted by the gallbladder

What compound secreted during digestion emulsifies fats? What organs make and store this?

Phospholipid

A type of lipid in which a fatty acid is combined with another compound that contains phosphate; soluble in water

A micelle is a spherical compound made up of bile salts and biliary phospholipids that transports lipid digestion products to the enterocytes for absorption. Chylomicron is a specific lipoprotein produced in the mucosal cell of the intestine (enterocytes); transports dietary fat (lipids) out of the intestinal tract.

What transports fats into the enterocyte during digestion? What is the difference between a micelle and a chylomicron?

A monoacylglyceride just has one fatty acid attached to a one-carbon glycerol backbone. Triglyceride is a molecule consisting of three fatty acids attached to a three-carbon glycerol backbone; most of the fat we eat is in the form of triglycerides (form that body fat is stored).

What is the difference between a monoacylglyceride and a triglyceride?

Amino acids

The smallest molecules that make up proteins are called what?

Essential amino acid

Amino acid that is not produced by the body or not produced in sufficient amounts so that they must be obtained from food

Limiting amino acid

The essential amino acid that is missing or in the smallest supply in the amino acid pool and is thus responsible for slowing or halting protein synthesis

Complete protein

A source of protein that contains an adequate proportion of all nine of the essential amino acids necessary for the dietary needs of humans or other animals

Mucus layer protects the lining of the stomach from the acid in the gastric juices

What are the functions of mucus in the stomach?

The inactive enzyme pepsinogen is activated by HCl and converts this enzyme to pepsin, which begins the digestion of proteins into smaller components

What does HCl activate in the stomach?

The pancreas manufactures, holds, and secretes digestive enzymes. Bicarbonate is secreted to neutralize acidic chyme. Cells lining the stomach secrete bicarbonate, which neutralizes acid near the surface of the stomach's lining and also assists in protecting this lining.

What compound neutralizes stomach acid? What organ secretes this?

Parietal cells secrete intrinsic factor to absorb vitamin B12

Intrinsic factor is needed to absorb which nutrient? Which cells in the stomach secrete this?

Gastrin, secreted by stomach-lining cells called G cells, stimulates gastric glands to secrete a digestive fluid referred to as gastric juice

Which hormone triggers the stomach to release digestive juices? What is this digestive juice called?

Nitrogen balance

A measure of nitrogen input minus nitrogen output

Marasmus

Disease that results from grossly inadequate intakes of protein, energy, and other nutrients. People with this disease slowly starve to death. People suffering are described to look like "skin and bones."

Kwashiorkor

Disease that occurs in developing countries when infants are weaned early due to the arrival of a subsequent baby. It develops quickly causing a person to look swollen, particularly in the belly. This is because the low protein content of the blood is inadequate to keep fluids from seeping into tissue spaces.

Sickle cell anemia

Inherited disorder of the red blood cells in which a single amino acid present in hemoglobin is changed. Red blood cells are shaped like a crescent. These cells cannot travel smoothly through blood vessels, causing cell breakage and anemia. They are hard and sticky.

Denaturation

The process by which proteins uncoil and lose their shape and function when they are exposed to heat, acids, bases, heavy metals, alcohol, and other damaging substances

Transamination

Process of transferring the amine group from one amino acid to another in order to manufacture a new amino acid

Deamination

The process by which an amine group is removed from an amino acid. To use proteins for energy, the nitrogen (or amine) group is removed from the amino acid.

Hydrolysis reaction

A catabolic process in which large, chemically complex compound is broken apart with the addition of water

-Ex: Pepsin is an enzyme that breaks down proteins into short polypeptides and amino acids via this process

Condensation reaction

An anabolic process in which smaller, chemically simple compounds are joined with the removal of water

-Ex: disaccharides contain two molecules, as a result of condensation (Lactose: one glucose molecule + one galactose molecule)

The first step begins with the entry of acetyl CoA into the cycle. 2-carbon acetyl CoA reacts with 4-carbon oxaloacetate to form 6-carbon citrate.

What is the starting molecule in the TCA cycle?

Anabolism

The process of making new molecules from smaller ones; it is critical for growth, repairing and maintaining the body's tissues, and synthesizing the chemical products essential for human

Catabolism

The breakdown or degradation of larger, more complex molecules to smaller, more basic molecules; releases chemical energy

Pyruvate will be converted to acetyl CoA

Aerobic environment means that pyruvate will be converted to what molecule?

Pyruvate converts to lactate then back to glucose

In the anaerobic environment, pyruvate will be converted into what molecule?

o The carbon skeletons of glucogenic amino acids are converted to pyruvate (used to resynthesize glucose or converted to acetyl CoA); amino acid that can be converted to glucose via gluconeogenesis.

o The carbon skeletons of ketogenic amino acids are converted directly to acetyl CoA for the synthesis of free fatty acids.

What is the difference between a ketogenic amino acid and a glucogenic amino acid? What is their definition?

Glycogen is stored in the liver and muscles . Liver glycogen maintains blood glucose levels and supports the needs of our cells (meaning the glycogen release from muscles will not raise blood glucose instead it continually provides energy to muscles during intense exercise).

Can glycogen released from the muscle raise your blood glucose?

High-glycemic carbohydrate foods, such as white bread, candy made from dextrose, or maltodextrin supplements, will replenish glycogen stores when consumed immediately following workouts since muscle tissue is sponge-like and therefore will rapidly soak up glucose from the high-glycemic carbohydrates

How can you restore glycogen in muscle?

The protein intakes suggested for active people range from 1.0 - 1.8 grams per kg body weight. At the lower end of this range are people who exercise four to five times a week for 30 min or less. At the upper end are athletes who train five to seven times a week for more than an hour a day. Protein intakes as high as 1.8 - 2.0 grams per kg per day may help prevent loss of lean body mass during periods when an athlete is restricting energy to promote fat loss.

How do you determine protein requirement?

Primary role of B-vitamins is to act as coenzymes in metabolic processes (facilitate the production of energy within the body).

What is the primary role of B-complex vitamins?

TPP=Thiamin

PLP=Vitamin B6

NADP=Niacin

What vitamins are parts of TPP? PLP? NADP?

Ariboflavinosis

Riboflavin deficiency: sore throat, swollen mucosal membranes; associated with protein-energy malnutrition and alcoholism

Pellagra

Occurs when an individual is deficient in the vitamin Niacin (B3)