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What are the abundant elements of life?
Carbon, hydrogen, nitrogen, oxygen, phosphorous
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What are the trace elements?
Calcium, chlorine, cobalt, coppers, iodine, iron, manganese, magnesium, potassium, sodium, sulohur, selenium, zinc
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What are the detectable elements?
Boron, bromine, chomium, molubdenum, silicon, tin
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What are the macromolecules?
carbohydrats, proteins, nucleic acids, lipids
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What are carbohydrates?
Polymers of simple sugars
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How do nutrients effect genes?
A nutrient an interact with cellular machinery and influence the ay the cell uses the nutrient
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What is the lac operon of e. coli?
Lac operon is found in e. coli which turns on genes to process lactose
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When does a cell need an increase in nutrients?
When a cell is growing, it needs an increase in the concentration of nutrients
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What is the N-terminus?
N-terminus corresponds to the 5' end of a gene
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How many standard amino acids are there?
20
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How are nucleic acids linked together?
phospho-diester link
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How does our body use nucleic acids?
Maintained in permanent storage
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What are lipids composed of?
Composed of fatty acids, cholesterol, and others
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What is the functional classification of lipids?
Lipids are a diverse set of organic compounds that are not soluble in water but are soluble in organic solvents (such as alcohol or ether)
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What is palmitoleic acid?
- 9-hexadecanoic acid
- C16:1- n-7 cis
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What is oleic acid?
- 9-octadecanoic acid
- C18:1, n-9 cis
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What is elaidic acid?
- 9-octadecanoic acid
- C18:1, n-9 trans
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What is linoleic acid?
- 9,12-octadecadienoic acid
- C18:2, n-6,9 all cis
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What is alpha-linolenic acid?
- 9,12,15- octadecatrienoic acid
- C18:3, n-3,6,9 all cis
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What is gamma-linolenic acid?
- 6,9,12- octadecatrienoic acid
- C18:3, n-6,9,12 al cis
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What is columbinic acid?
- 5,9,12- octatrienoic acid
- C18:3, n-6 cis, 9 cis, 13 trans
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What is eicosenoic acid?
- 11-eicosenoic acid
- C20:1, n-9 cis
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What fatty acid is olive oil rich in?
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What fatty acid is saddlower oil rich in?
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What fatty acid is lard, beef tallow rich in?
Rich in palmitic (C16:0) and stearic (C18:0)
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How can you easily tell the relative number of double bonds in a fat?
State at room temperature
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What are the different uses of fatty acids?
- Energy source
- Structural component
- Subtrate for the synthesis of signaling molecules
- Covalend modification of proteins
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What are triacylglycerols?
A glycerol with 3 fatty acids
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Which cells in the body can make cholesterol?
- Every body in the body has the ability to make cholesterol
- Begins with acetyl-CoA
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What does colesterol look like?
Long and flat
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What does cholesterol do to arteries?
Makes them stiff
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What is the key enzyme needed for synthesis of cholesterol?
HMG-CoA
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Can cholesterol be oxidized to produce energy?
No, the formation of cholesterol is not reversible
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What is cholesterol a precursor for?
Highly bioactive molecules
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What are 3 different uses for cholesterol?
- Substrte for the synthesis of steroid hormones and vitamin D
- Substrate for the synthesis of bile acids
- Required for control of membrane fluidity
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How does cholesterol affect membrane fluidity?
- The more cholesterol in the membrane, the more fluid it is
- If the membrane is too rigid, proteins cant move and it wont work
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Why does cholesterol build up in the body?
It cant be destroyed
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What does our body do with an excess of cholesterol?
Synthesize it into cholesteryl esters
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What is inactive cholesterol?
- When it is esterified it is metabolically inactive (lipid droplet)
- Once there is a need for cholesterol it liberates the fatty acid and the cholesterol is free to use
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What is a nutrient?
A nutrient is either a chemical element or compound that is used in the metabolic processes of, or forms an integral component of the physiology of an organism
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What is a macro nutrient?
A nutrient needed in large quantities
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What is a micro nutrient?
A nutrient needed in smll quantities
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What are the different uses of nutrients?
Some nutrients are used as energy sources, or used to build structures; others provide support functions in metabolism
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What are the 3 macronutrients?
- carbohydrates
- proteins
- fats
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What are 2 types of micronutrients?
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What are micronutrients typically used for?
Typicall act as co-substrates, or as enzyme cofactors which determine enzymatic activity
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What is an essential nutrient?
the absoence of the nutrient from the diet results in characteristic signs of a deficiency disease and these signs are prevented only by the nutrient itself or a specific precursor of it
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What are the essential amino acids?
- Isoleucine
- Leucine
- Lysine
- Methionine
- Phenylalanine
- Threonine
- Tryptophan
- Valine
- Histidine
- Arginine (in children and special cases)
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What are essential fatty acids?
Humans cannot make fatty acids th double bonds between carbons located at position 8 or less (counting from the methyl end)
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What are 2 essential fatty acids?
- linoleic acid (C18:2 n-6)
- Linolenic acid (C18:3 n-3)
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What are the essential faty soluble vitamins?
A, D, E, K
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What are the essential water-soluble vitamins?
B1, B2, B3, B6, B5, B9, B12, B7, C, Choline
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What are the uses for choline?
- Substrate for phosphatidylcholine biosynthesis
- Ensures the structural integrity and signaling functions of cell membranes
- Source of methyl groups
- Used to make a variety of very important metabolites
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What is the substrate for phosphatidyl choline biosynthesis?
choline
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What is phosphatidylcholine?
membrane
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What is the de novo synthesis of choline?
- Three sucessie methylations of the phosphatofulethanolamine headgroup generates phosphatylcholine
- Choline can be released from phosphatidylcholine
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What are the essential macrominerals?
Calcium, chloride ion, phosphorous, potzssium, magnesium, sulphur
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What are the essential trace minerals?
Cobalt, copper, fluoride ion, iodine, iron, manganese, nickel, sodium, selenium, zinc
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What are phytochemicals?
a broad and diverse group of plant derived compounds
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What are flavonoids?
a subclass of phytochemicals throught to have beneficial effects on health
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What are essential fatty acids for?
- EFAs are substrates for a class of molecules in the body called eicosanoids (prostaglandins, leukotrines, and thromboxanes)
- EFAs are important in immune function, inflammatory respose, blood clotting, vasodilation, kidney function, conitive function
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What happens with essential fatty acid deficiency?
Growth retardation, sparse hair growth, dry skin and scaling (excema), general weakness, depression, poor wound healing, increased susceptibility to infection, edema, vision problems; neurologic problems (severe cases)
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What happens with essential fatty acid excess?
- Does not appear to cause severe problems
- May cause excessive bleeding (slow blood clotting)
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Where is vitamin A found?
brightly colored fruits and vegetables
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What is vitamin A essential for?
Essential for proper maintenance of epithelial cells; deficiency of this vitmain causes mucus-secreting cells to be replaced by keratin producing cells, leading to zerosis (abnormal dryness)
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Which vitamin primarily affects eye function and how?
- Vitamin A
- Deficiency can cause night blindness, eye xerosis which causes ulcerations and eventually leading to blindness
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Why are people with diseases involvinv the absorption of lipids at risk for vitamin A deficiency?
Vitamin A is a fat soluble vitamin
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What are some side effects of vitamin A excess?
- Birth defects
- Reduced bone mineral density
- Weight loss, headache, vision problems, dry itchy skin, hair loss, anemia, teeth discoloration, enlarged liver and spleen
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What is iron?
A transition metal; classified as a 'micromineral'
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How is iron used in the body?
used as a prosthetic group by maby biologically important proteins eg. heme groups of hemoglobin, myoglobin, cytochrome c, peroxidases, hydroxylases, generally found in enzymes involved in carrying or metabolizing oxygen
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How much iron does the average person contain>
- approx 3-4 grams
- about 60% of this amount in found in blood
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How do we lose iron?
shedding of epitherlial surfaces, through intestine (occult blood loss), menstruation, lactation
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What are the signs of iron deficiency?
Amenia, low bloor idon: pale skin, tired and weakness, difficulty maintain body temperature, shortness of breath, an inflamed tongue, diminished cognitive function, decreased immune function
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Who are at most risk for iron deficiency anemia?
Alcoholics, patients with infectious, inflammatory, or neoplastic diseases (cancer)
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What is iron toxicity with genetic basis?
African hemochromatosis, porphyria, hyperferritinemia, heriditary hemocromatosis
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What is secondary hemochromatosis?
Caused by excessive alcohol consumption; excessive use of dietary iron supplements
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What is iodine essential for?
- Necessary for normal thyroid function
- Essential substrate for the synthesis of thyroid hormones
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What are thyroid hormones used for?
Conrol many aspects of energy (carbohydrate and fat) metabolism; ligants of TR receptor (a transcription factor belonging to the nuclear receptor superfamily of transcription factors)
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What are some sources of iodine?
Seafood, kelp, dairy products,; most common 'modern' source is iodized table salt
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What are some side effects of iodine deficiency?
Increased fetal and infant mortality, neurological defects and mental retardation (cretinism), decreased reproductive fitness, hypothyroidism, goiter (hypertrophy of the thyroid gland)
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What are some secondary thyroid related disorders?
Anemia, arthritis, eye enlargement, and inflammation, hair loss and premature graying of hair; inflammatory bowel diseases, depression
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What are goiters caused by?
- Caused by iodine deficiency; impaired thyroid hormone synthesis
- Also caused by excessive iodine, which results in the inhibition of thyroid hormone production
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What are some side effects of iodine excess?
- Skin ulceration ('kelp acne', high incidence in Japan where kelp is consuemed in large quantities)
- Impairs thyroid hormone production and causes goiter in response to decreased thyroid hormone concentration
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What is the purpose of a lipocyte?
To store fat until it can be used for energy
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Do adipocytes die?
No, they just get smaller
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Which cells typically produce cholesterol?
liver cells
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Where do we get cholesterol from in our diet?
Meat and dairy products
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What are some problems with nutrient processing?
- Inborn errors of metabolism
- Acquired metabolic syndromes
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What determines how individuals percieve bitter taste?
Variateions in bitter taste receptors
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What is lactase?
An enzyme produced by the intestine that digests lactose
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Why is lactose intollerance so common?
Because milk is not naturally consumed by adults
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What is LCT gene?
- encodes lactase
- expression normally shits down after weaning
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What gene variation determines lactose intollerance>
MCM6
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What gene is thought to be respinsible for the absorption of dietry cholesterol in the intestine?
NPC1L1
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What can cholesterol import be inhibited by?
Cholesterol import can be inhibited by ezetimibe, a drug that interacts with NCP1L1
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