AP2 - Nutrition
4 Processes that provide for the continual exchange of water and solutes among body fluid compartments
Filtration Reabsorption Diffusion Osmosis
Two Essential Fatty Acids
Linoleic Acid Linolenic Acid
Minerals with unknown or no function
Aluminum Boron, Silicon, Molybdenum
Variety
no one food or food group provides all of the nutrients and food types that the body needs
Essential nutrients
specific nutrient molecules that the body cannot make in sufficient quantity to meet its needs and thus must be obtained from the diet
Amino acids are not saved for future use
they are either oxidized to produce ATP, used to synthesize new proteins for growth and repair of body tissues, or converted into triglycerides and stored in adipose tissue
Thiamin (B1)
• Deprive your body of thiamin and you deprive every cell of its ability to use energy; helps reactions that break down glucose, make RNA and DNA, and produce energy-rich molecules that power protein synthesis. • Helps synthesize and regulate neurotransmitters.
Regulation of water and solute loss
• Elimination of excess body water or solutes occurs mainly by controlling the amount lost in urine
Chromium
• Enhances the ability of insulin to move glucose into cells. • Nucleic acid metabolism, growth, and immune functions.
Vitamin B12 (Cobalamin)
• Essential to the conversion of folate to an activated form. • Deficiency will produce Folate deficiency symptoms. • Helps maintain the Myelin sheath.
Molybdenum
• Functions as a co-factor for several enzymes
Iodine
• Help regulate body temperature, basal metabolic rate, reproduction, and growth
Phosphorus
• Helps activate and deactivate enzymes during the final steps in the extraction of energy from macronutrients. • a component of ATP, DNA and RNA, and phospholipids
Sulfur
• Helps stabilize the shapes of proteins like those in skin, hair, and nails. • the liver's detoxification pathways require sulfur to maintain its pH
Carbohydrate (Glucose) Metabolism
• If cells require ATP immediately, they oxidize the glucose. • If glucose is not immediately needed, it may be converted to glycogen for storage in liver cells and skeletal muscle fibers. • if there is sufficient glycogen, the glucose can be transformed into triglycerides for storage in adipose tissue, which can be converted back later.
Zinc
• Important for normal growth of children and sexual maturation of adolescents. • Important for certain tissues with high turnover rates (lining of the GI tract, skin cells, immune cells, and blood cells). • Vital to a vigorous immune response. • Essential to the proper development and maintenance of the immune system. • Without zinc, the body could not fight pathogens; even mild deficiency may increase the risk of infection
Manganese
• Involved in energy metabolism, urea formation, cartilage-building, and is a component of an antioxidant enzyme.
Water loss occurs in 6 ways:
• Kidneys excrete in urine. • Evaporates from the skin surface • Lungs exhale as water vapor • Gastrointestinal tract eliminates in feces • Lost in menstrual flow of women of reproductive age • Through extreme sweat, vomit, or diarrhea
Intracellular Fluid
• Liquid inside cells. • about 2/3rd of body fluid. • Cytosol
Arsenic
• May actually be essential in miniscule amounts. • Deprived-laboratory animals have poor growth and abnormal reproduction.
Lipid Metabolism
• May be catabolized to produce ATP. • If there is no immediate need to use lipids for ATP, they are stored as triglycerides in adipose tissue throughout the body and in the liver. • A few lipids are used as structural molecules or to synthesize other substances.
Micronutrients
• Nutrients the body needs in small quantities • Includes Vitamins, Minerals
Riboflavin (B2)
• Part of reactions that extract energy from glucose, fatty acids, and amino acids. • Supports antioxidant activity and participates in reactions that remove ammonia.
Magnesium
• Participates in 300+ enzyme-driven reactions including those in DNA and protein synthesis, blood clotting, muscle contraction, and ATP production. • Absence of magnesium would halt all cellular activity.
Niacin (B3)
• Participates in at least 200 metabolic pathways; needed to synthesize fatty acids.
Copper
• Participates in dozens of reactions (energy release, skin pigment production, production of collagen and elastin). • plays a role in maintaining nerve health, immune function, and heart function
Boron
• Plays a role in promoting bone metabolism, brain health, and cancer prevention.
Selenium
• Prevents oxidative damage. • involved in thyroid metabolism. • important to immune function. • may have a role in cancer, heart disease, arthritis, and HIV treatment and prevention
Vitamin K
• Produced by bacteria in the gastrointestinal tract and then absorbed
Protein metabolism
• Proteins are broken down into amino acids
Role of Minerals
• Regulate enzymatic reactions. • Catalyze the conversion of ADP to ATP, • Control the pH of fluids, • Regulate osmosis, • Generate nerve impulses
Vanadium
• Scientists aren't sure what it does yet
Blood Vessel Walls
• Separate the interstitial fluid from blood plasma
Plasma Membrane
• Separates intracellular fluid from the surrounding interstitial fluid
Iron
• Transports oxygen (hemoglobin and myoglobin). • Essential component of hundreds of enzymes, many of which are involved in energy production and amino acid metabolism. • Plays a role in the immune system and in brain development (involved in producing myelin sheaths and neurotransmitters).
Vitamin A
• Vision (deficiency may cause night blindness and impaired color vision). • Maintains healthy cells (especially epithelial). • Fights infections and bolsters immune function. • Promotes growth and development.
Fluid Balance
• When the required amounts of water and solutes are present and are correctly proportioned among the various compartments
Alkalosis
• a condition in which arterial blood pH is above 7.45. • over-excitability in both the CNS and peripheral nerves. • nervousness, muscle spasms, convulsions, and death
Acidosis
• a condition in which arterial blood pH is below 7.35. • depression of the CNS. • if pH falls below 7, it may result in disorientation, coma, or death.
Heat Exhaustion
• a condition in which the core temperature is generally normal or a little below and the skin is cool and moist due to profuse perspiration. • usually characterized by loss of fluid and electrolytes resulting in muscle cramps, dizziness, vomiting, and fainting.
Heat Stroke
• a severe and often fatal disorder caused by exposure to high temperatures. • blood flow to the skin is decreased, perspiration is greatly reduced, and body temperature rises sharply because of failure of the hypothalamic thermostat
Kilocalories
• amount of energy (heat) it would take to raise the temperature of 1 kg of water by 1 degree Celcius. • units used to measure energy. • food energy is measured in kilocalories (1,000 calories = 1 kilocalorie)
Malnutrition
• an imbalance of total caloric intake or intake of specific nutrients which can be either inadequate or excessive.
Exhalation of Carbon Dioxide
• an increase in the carbon dioxide concentration in body fluids increases hydrogen ion concentration and thus lowers the pH (more acidic). • a decrease in carbon dioxide concentration of body fluids raises the pH (more alkaline). • Changes in the rate and depth of breathing can alter the pH of body fluids within a couple of minutes
Proteins from worn-out cells around the body
• broken down into amino acids. • some are recycled, others are converted to fatty acids, ketone bodies, or glucose
Catabolism
• chemical reactions that break down complex organic compounds into simple ones. • release the energy stored in organic molecules which can then be used to power anabolic reactions. • About 40% of the energy released in catabolism is used for cellular functions, the rest is converted to heat.
Anabolism
• chemical reactions that combine simple substances into more complex molecules. • use more energy than they produce. • The formation of peptide bonds between amino acids to form proteins.
Calorie
• general term for energy in food and used synonymously with the term energy. • often used instead of kilocalorie on food labels, in diet books, and in other sources of information. • When we discuss the "calories" in a food, we are really describing kilocalories
Thirst Center
• hypothalamus • governs the urge to drink
Antidiuretic Hormone
• major hormone that regulates water loss. • release is stimulated by an increase in the osmotic pressure of body fluids. • Intake of plain water decreases the osmotic pressure of blood and interstitial fluid, which decreases ADH causing greater water excretion through urine
Electrolytes
• most solutes in the body. • inorganic compounds that break apart into ions when dissolved in water. • the main contributors to the osmotic movement of water. • Because intake of water and electrolytes rarely occurs in exactly the same proportions as their presence in body fluids, the ability of kidneys to compensate is of utmost importance in the maintenance of homeostasis.
Vitamins
• organic nutrients required in small amounts to maintain growth and normal metabolism. • do not provide energy or serve as the body's building materials. • Most cannot be synthesized by the body and must be ingested
Metabolic Water
• produced in the body during chemical reactions. • mostly produced during aerobic cellular respiration.
Lipoproteins
• spherical particles with an outer shell of proteins, phospholipids, and cholesterol molecules surrounding an inner core of triglycerides and other lipids. • repackaged to be water-soluble for transport in the blood
Ketone Bodies
• substances produced during normal fatty acid catabolism by the liver
Buffers
• substances that act quickly to temporarily bind hydrogen ions removing them from the solution but not from the body. • may also release hydrogen ions if the concentration is too low
Protein Anabolism
• the formation of peptide bonds between amino acids to produce new proteins
Osmosis
• the primary means of water movement between intracellular fluid and interstitial fluid, the concentration of solutes in these fluids determines the direction of water movement
Lipolysis
• the process by which triglycerides are split into glycerol and fatty acids
Provitamins
• the raw materials from which some vitamins can be assembled. (i.e. beta-carotene to form vitamin A)
Kidney Excretion
• the slowest mechanism for removal of acids. • the only way to eliminate most acids that form in the body.
Metabolism
• the sum of all of the chemical reactions of the body. • an energy-balancing act between anabolic and catabolic reactions
Body Fluids
• the water and dissolved solutes in the body. • In lean adults, body fluids make up about 55-60% percent of total body mass. • present inside cells and outside cells
Ketosis
• when the concentration of ketone bodies in the blood rises above normal. • prolonged ketosis can lead to acidosis, which can result in death
Dehydration
• when water loss is greater than water gain. • a decrease in volume and an increase in osmotic pressure of body fluids. • When body mass decreases by 2% due to fluid loss, mild dehydration exists.
Vitamin E
▪ Defends against chronic diseases associated with aging. ▪ Antioxidant that protects vulnerable polyunsaturated lipids in cell membranes, in the blood, and elsewhere; high intakes may lower the risk of some chronic diseases especially heart disease; vitamin E has possible preventive role in cancer, eye disorders, immune function, and cognitive declines.
Proportionality
eating more of some types of foods than others
6 categories of nutrients
carbohydrates lipids proteins water minerals vitamins
When more calories are consumed than are needed to satisfy ATP needs
carbohydrates, proteins, and fats all have the same chance of being converted into triglycerides and stored in adipose cells.
When the diet contains a large amount of protein
cellular metabolism produces more acids than bases and thus tends to acidify the blood
Nutrients
chemical substances in food that body cells use for growth, maintenance, and repair, whose absence in the body would result in a deficiency
Proteins may function as...
enzymes, hemoglobin, antibodies, clotting factors, hormones, contractile elements in muscle fibers, and structural components.
2 ways body can get water
ingestion metabolic reactions
Removal of hydrogen ions from body fluids and subsequent elimination from the body depends on three major mechanisms
1. Buffers 2. Exhalation of Carbon Dioxide 3. Kidney Excretion
Ions serve 4 general functions in the body
1. Control the osmosis of water between fluid compartments. 2. Help maintain acid-base balance 3. Carry electrical current 4. Serve as cofactors (for optimal activity of enzymes)
Thirst is triggered by
1. Decrease in blood volume. 2. Dryness in the mouth due to decreased flow of saliva.
2 barriers separating intracellular fluid, interstitial fluid, and blood plasma
1. Plasma Membrane 2. Blood Vessel Walls
3 Functions of food molecules absorbed by the GI tract
1. Supply energy 2. Serve as building blocks 3. Storage for future use
Acid-Base Balance
A major homeostatic challenge is keeping the hydrogen ion level (pH) of body fluids in the appropriate range (maintenance of acid-base balance)
Fat-Soluble Vitamins
A, D, E, and K
Vitamin D
Considered both a vitamin and a hormone because vitamin D made in one part of the body regulates activities in other parts. • the primary role of calcitriol is to maintain blood calcium and phosphorus levels within a normal range. • Essential for bone health at all ages. • May have a role in cardiovascular disease, type 2 diabetes, and immunity and muscular disorders. • Role in preventing cancer cells from dividing. • Anti-inflammatory properties
Water-Soluble Vitamins
Eight B's and a C
In 2011, the USDA MyPlate replaced the USDA MyPyramid
Emphasizes proportionality, variety, moderation, and nutrient density in a health diet
Minerals
Inorganic elements that constitute about 4% of the total body weight and are concentrated most heavily in the skeleton.
Electrolytes in Body Fluids
Ions are formed when electrolytes break apart
One important function of the kidneys
help maintain fluid balance in the body
KCal per Nutrient
• 1 gram of Protein = 4 kcal • 1 gram of Carbohydrate = 4 kcal. • 1 gram of Lipid = 9 kcal. • 1 gram of Alcohol = 7 kcal
Extracellular Fluid
• 1/3rd of body fluid. • Includes all other body fluids (interstitial fluid and plasma)
Non-Essential Amino Acids
• 10 out of 20 are synthesized by the body
Essential Amino Acids
• 10 out of 20 that must be present in the diet
Blood Plasma
• 20% of Extracellular Fluid. • the liquid portion of the blood
Interstitial Fluid
• 80% of Extracellular Fluid. • Occupies the spaces between tissue cells. • Includes lymph, cerebrospinal fluid, synovial fluid, aqueous humor, vitreous body, endolymph, perilymph, and pleural, pericardial, and peritoneal fluids of serous membranes
Fluoride
• 99% of fluoride is in the bones and teeth, where it promotes deposition of calcium and phosphate. • inhibits bacterial activity that eats away tooth enamel and shifts the balance toward depositing minerals. • inhibits tooth decay and loss of tooth enamel. • may play a role in bone health
Vitamin B6 (Pyridoxine)
• A coenzyme for more than 100 different enzymes; without vitamin B6, the body cannot make non-essential amino acids and must get them from food only. • Helps make glucose from amino acids; helps release glucose from glycogen. • Supports white blood cell synthesis and a healthy immune system; helps synthesize hemoglobin for healthy red blood cells. • Helps produce a number of major neurotransmitters.
Fat-Soluble Vitamins
• A, D, E, and K. • Absorbed along with dietary lipids in the small intestine. • Cannot be absorbed in adequate quantities unless they are ingested with other lipids.
Potassium
• Along with sodium, help contract muscles, transmit nerve impulses, and regulate blood pressure and heartbeat. • affects blood pressure. • diets high in potassium and low in sodium greatly improve blood pressure and risk of coronary heart disease
Biotin (B7)
• Amino acid metabolism including the conversion of amino acids to glucose, fatty acid synthesis, release of energy from fatty acids, and DNA synthesis.
Vitamin C
• An antioxidant that works with vitamin E. • Antiscorbutic (Antiscurvy). • Necessary to form collagen and to make other essential compounds such as thyroid hormone, steroid hormones, bile salts, and serotonin; enhances the absorption of iron from plant foods; enables immune cells to function effectively. • Reputed to prevent or cure the common cold; regular supplementation has been found to have a modest effect on shortening the duration of the common cold.
Water-soluble vitamins
• B vitamins and vitamin C. • Dissolved in body fluids. • Excess quantities are not stored but instead excreted in the urine
Vitamin K
• B.lood clotting and helps with bone formation, increases bone strength, and decreases fractures
Silicon
• Believed to help strengthen collagen and elastin and play a role in bone formation and growth
Calcium
• Bone structure. • Muscle contraction. • Metabolism - helps regulate a number of cellular processes including cell division, cell proliferation, ciliary action, and cell secretions. • Blood cannot clot without calcium. • Nerve cells need calcium to transmit signals
Antioxidant Vitamins
• C, E, and beta-carotene. • Inactivate oxygen free radicals to protect against cell membrane and DNA damage. • protect against some kinds of cancer, reduce the buildup of atherosclerotic plaque, delay some effects of aging, and decrease cataract formation in the lenses of the eyes
Nickel
• Can activate or inhibit a number of other enzymes. • Specific function in humans has not been identified
Pantothenic acid (B5)
• Critical for extracting energy from nutrients and for building new fatty acids.
Sodium
• Critical for regulating cellular fluid, total body fluid, blood pressure, and pH. • Movement of sodium back and forth across cell membranes helps regulate the transit of other substances that tag along or travel in the opposite direction. • Helps transmit nerve impulses and other electrical messages.
Folate (B9)
• Crucial to DNA synthesis and cell division, healthy embryonic development, amino acid metabolism, and the maturation of red blood cells and other cells.
Chloride
• Crucial to transmitting nerve impulses and to maintaining pH balance. • Component of hydrochloric acid in the stomach.
Dehydration triggers thirst
• Decrease in blood volume causes blood pressure to fall which stimulates the kidneys to releases renin to promote the formation of angiotensin II. • osmoreceptors in the hypothalamus and increased angiotensin II in the blood stimulate the thirst center in the hypothalamus