Chapter 11 - Micronutrients Flashcards
Two types of micronutrients
Vitamins
Minerals
Calories (vitamins and minerals)
Vitamins are noncaloric
Vitamins are
organic - contain element carbon
Minerals are
inorganic - no carbon
Sources of vitamins
Both plant and animal food sources
How are vitamins gouped?
By solubility (some disolve in water, others in fat)
Water-soluble vitamins
Vitamin C
B vitamins = thiamin, riboflavin, niacin, folic acid (folate), vitamin B-12 (cobalamin), vitamin B-6 (pyridoxine), biotin, and pantothenic acid
excreted in urine - toxicity is hard
not stored in body
Fat-soluble vitamins
Vitamins A (retinol), D, E, and K
Store it - limited capacity to excrete
Vitamin A = most common deficiency
Minerals are product of
cosmological processes
Plants and animals pick them up
Divalent cation
An ion with a double positive charge
Ex. iron, clacium, zinc, and copper
Bioavailability
The degree to which a nutrient is absorbed in digestion
Phytic acid (phytates)
Phosphorous compound found in some plant foods which will reduce mineral bioavailability
Oxalic acid
A compound found in some fruits and vegetables that reduces calcium absorption
Tannins
Reduce iron absorption
found in tea
Acid
increases the solubility of minerals
Presence of MFP factor (Meat-Fish-Poultry)
increases the absorption of plant forms of iron dramatically
Major minerals
Components of bone (calcium, phosphorous, and magnesium)
Electrolytes (sodium, potassium, and chloride)
Sulfur
*Concentrations up to 1100 grams*
Trace minerals
Iron, copper, zinc, iodine, selenium, and others
are components of enzymes
components of hormones
Most common mineral difficiency
Iron
Zinc
present in structure of nearly 100 enzymes
involved in cell replication and cell division
Ex. would healing,growth, strength gains
Excess amounts = diminish the immune response
Myglobin
An iron containing protein found in muscle cells
Moves oxygen into the cell
Iron
Ability to move electrons between atoms
involved in the development of the myelin sheath and of neurotransmitters
Metalloenzymes
Enzymes with iron, zinc, or other metals as part of their structure
Carcinogen
A cancer-causing compound
detoxified by iron
cofactor
binds to the enzyme to activate it
ex. iron
Vitamin B-12 (cobalamin)
produce and maintain the myelin sheath
Activates folate, and folate activates it
Deficiency of B-12
low intake of B-12
low intake of folate
failure to produce instrinsic factor
Results: severe neurological problems, numbness, paralysis
intrinsic factor
A substance secreted by the stomach needed for the absorption of vitamin B-12
Folate is necessary for
Development of spinal column during pregnancy
Spina bifida
A neural tube defect that can be characterized by problems in gait and mental retardation
*result of a low intake of folate*
Folate is also necessary for what
DNA synthesis
Deficiency - halt cell growth
fortification
the addition of a nutrient to a food
Potassium
Major positively-charged intracellular ion
critical in the conduction of nerve impulses
*can cause cardiac arrhythmia*
result of binging or sweating too much
Sodium
Exchanged with potassium to trigger muscle contraction
defiency: decrease performance capability and may cause muscle cramping
Chromium
Enhances the ability of insuline to bind to its receptor on the cell membrane
helps move glucose and amino acids into the cell
promotes synthesis and glycogen repletion
Pyridoxine (vitamin B6)
Necessary for the synthesis of non-essential amino acids
needed for neurotransmitter synthesis
defiency: neurological symptoms
Vitamin C
Acts as a cofactor, along with iroin, in the synthesis of collagen
collagen
a protein making up connective tissue
Scurvy
A disease caused by a defiency of vitamin C
free radical
An atom containing an unpaired electron in its outer shell, and making it very reactive
singlet
An unpaired electron in the outer shell of a free radical
Carcinogenesis
The process of cancer develoment
result of free radical damage to DNA
provitamin
A vitamin precursor
Used to prevent oxidative damage by reacting with free radicals
Vitamin C and free radicals
Donates electrons to free radicals
Deficiency of Vitamin E
Breakdown of red blood cells not protected against oxidative damage, called hemolysis
Most important job of Vitamin A
Defiency of Vitamin A
night blindness
Precursor
A chemical compound that can be readily made by the body into another compound
*Beta-carotene is a precursor to Vitamin A*
Differentiation
The process by which stem cells mature into specialized organ cells
Vitamin A is necessary for cell differentiation
erythrocytes
red blood cells
Anemia
A condition of having an insufficient number of red blood cells, resulting in a reduction of oxygen transport capacity and thus an inability to produce enough energy for the body
Folate is necessary for what?
DNA synthesis
Macrocytic anemia
Folate deficiency anemia characterized by very large red blood cells
Megaloblastic
Folate deficiency anemia characterized by very large red blood cells
Pernicious anemia
Vitamin B-12 deficiency anemia
Vitamin B 6 (pyridoxine) is necessary for what
The synthesis of hemoglobin
Ferritin
Storage protein for iron
Transferrin
Transport protein for iron
Vitamin K is important for what?
blood clotting
prothrombin
A blood clotting factor
Vitamin K is a coenzyme in the synthesis of this
Coenzyme
A substance, often a vitamin, that activates an enzyme
Pellagra
Niacin deficiency disease
Beri-beri
Disease caused by deficiency of thiamin
Thyroxine
Thyroid hormone
Regulates metabolism
Iodine is a component of it
Goiter
An enlargement of the thyroid gland seen in iron deficiency
hydroxyapatite
Compound of calcium and phosphorous that makes up bone
Epiphyseal plates
Sites of active growth in the bone
Remodeling
The continual process of bone formation and resorption
Osteoblasts
Cells that form bone, laying down protein matrix and mineral
Osteoclasts
Cells that break down bone and release mineral into the bloodstream
Resorption
Uptake of calcium from bone
Calcitonin
Hormone from the thyroid gland that lowers blood calcium
Parathyroid hormone
Hormone from the parathyroid gland that raises blood levels of calcium
Rickets
Bone deformation in growing children caused by vitamin D deficiency
Osteomalacia
Defiency disease in adults caused by vitamin D defiency
Osteocalcin
A protein involved in bone turnover, formed by vitamin K
Osteoporosis
A chronic disease usually seen in the elderly resulitng in porous, weakend bone prone to fracture
Whole food
A form in its natural state, as it came from farm, field, or other source, and still resembles that source
Fortified food
A food with added nutrients
The nutrients are not naturally present in the food
Supplement
Nutrient obtained in purified and concentrated form, and consume as a pill or drink
Retinol
The active form of vitamin A
Carotenoid
a group of chemicals where some are precursors of retinol
ex. beta-carotene
Beta-carotene
common plant precursor of retinol
