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Block 1 > Cell Bio > Flashcards

Cell Bio Flashcards

1
Q

What kind of interaction is H-bond?

A

electrostatic interaction b/w electroneg O and electropos H –> an attraction, not a real bond –> NOT a covalent bond b/c they’re not sharing e-

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2
Q

Relationship b/w entropy and polar solutes vs nonpolar solutes dissolving in water

A

entropy = favorable and releasing energy during solvation = good vs entropy = unfavorable but energetically more favorable to associate as 1 large unit than individually solvated

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3
Q

What are amphipathic molec and examples?

A

molec w/ polar and nonpolar groups. ex: fatty acids

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4
Q

Hydrophobic Effect

A

hydrophobic substances and water will separate to minimize interactions. nonpolar hydrophobic part face inward away from water, polar hydrophilic part face outward towards water –> most energetically favorable. this is how you get protein folding, phospholipid bilayer, DNA double helix

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5
Q

How to find equil constant/Keq? What are the trends of Keq?

A

Keq = ([C]^c * [D]^d)/([A]^a * [B]^b). EXPONENTS ARE FROM COEFF
[prod]/[react]. Keq < 1 or large neg exponent –> favors reactants, Keq = 1 –> equil, Keq > 1 or large pos exponent –> favors products

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6
Q

How to calculate pH vs pOH?

A

-log[H+] = 1/log[H+] vs -log[OH-] = 1/[OH-]

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7
Q

pH > pKa meaning

A

pH < pKa –> exist in protonated form, acid > conj base

pH > pKa –> exist in deprotonated form, base > conj acid

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8
Q

What is a buffer? Why does H3PO4 make a good buffer?

A

slns that resist changes in pH as acid and base are added (try to keep pH constant); most buffers consist of weak acid & its conjugate base. b/c it has 3 H to get rid off –> their pKas = across the entire pH scale

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9
Q

strong vs weak acid. strong vs weak base

A

acids donate H+. 100% dissociates, irreversible, HA -> H+ + A- vs partially dissociates, reversible (dissociates & reassociates), HA <-> H+ + A-. base accepts H+. will combine w/ free H+, H+ + B -> BH+ vs reversible (dissociates & reassociates), B + H+ <-> BH+

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10
Q

How to find Ka of weak acid? What are the trends of Ka?

A

Ka = [H+][A-]/[HA]. Ka>1 –> favors [H+][A-] (prod), Ka<1 –> favors [HA] (react)

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11
Q

Know the Hendersen-Hasselbach eqn. What is this used for?

A

pH = pKa + log[A-]/[HA]; pKa = CONSTANT. buffer slns

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12
Q

Half-equivalence point

A

midpoint of buffering region in which half of titrant has been de/protonated thus [HA] = [A-]; pH = pKa

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13
Q

acidemia vs alkalemia. what’s body’s physiological pH?

A

blood pH < 7.35 vs blood pH > 7.35. 7.35-7.45

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14
Q

bicarbonate buffer system

A

CO2(g) <-> CO2(d) + H20 via carbonic anhydrase <-> H2CO3 <-> H+ + HCO3-
1st and 3rd steps = spontaneous. pKa carbonic acid = 6 –> pH > pKa –> likely to stay as H+ + HCO3-

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15
Q

hyperventilation vs hypoventilation (bicarbonate buffer system)

A

if you’re hyperventilating –> expelling too much CO2 –> system moves left –> blood [H+] drops –> pH dec => respiratory alkalosis vs if you’re hypoventilating –> not expelling CO2 –> system moves right –> blood [H+] inc –> pH dec –> respiratory acidosis

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16
Q

malnutrition and examples

A

too much or too little nutrition. ex: stunting, wasting, obesity

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17
Q

each nutrient has its own set of?

A

DRI: Dietary Reference Intake. 4 categories: estimated avg requirements, recommended dietary allowance, adequate intake, tolerable upper limits

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18
Q

importance of nutrient balance (7)

A

mind & spirit, immune & inflamm balance, GI balance, structural balance, hormonal & neurotransmitter balance, energy production/oxidative stress, detox & biotransformation

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19
Q

biochem principles in nutrition

A

water = medium, macronutrients = substrate (ex: carb, fat, protein), micronutrients = catalysts (ex: vitamins and minerals)

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20
Q

glycogen vs liver glycogen vs muscle glycogen

A

mainly located in liver and muscle (glu residues joined together to make polysaccharides) vs maintains blood glu levels b/w meals, stores energy during the day, can break down into glu anytime vs supplies energy for contraction during exer, only break down into glu during exer

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21
Q

fat vs carbs vs protein

A

located in adipose tissue (triglyceride - glycerol backbone + 3 fatty acids (fatty acids can be sat, monounsat, or polyunsat)), efficient fuel storage (9 kcal/g), more [H] & yield more energy when [O], aids in absorption of fat-soluble vit and carotenoid vs CHO, 4 kcal/g, glycogen in liver and muscle vs made of 9 essential aa and 11 nonessential aa, 4 kcal/g, not a primary fuel source, excess protein –> stored as fat; free aa pool = used in 3 ways: make new proteins, precursors for synthesis of nitrogen-containing cmpds (RNA, DNA, Heme), can be [O] for energy

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22
Q

how to distinguish scientific evidence from marketing strategies

A

ask 7 questions: how does study fit into entire body of evidence on topic? is the story reporting results of one story? how large is the study? was study done on animals or humans? did study look at real dz endpoints like heart dz or osteoporosis? how was diet assessed? what type of study was it? (best if it was randomized clinical trials of dietary interventions on hard endpoints)

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23
Q

What does Nutrient Recommendations and Dietary Guidelines 2015-2020 focus on?

A

healthy eating patterns, NOT individual nutrients or food in isolation; intended for ages 2+; dec sodium, added sugar, alc, sat fat and trans fat; inc fruits/veggies, whole grains, lean protein, fat-free low-fat dairy, fiber, potassium, calcium & vit D

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24
Q

how to eval nutrition status: ABCDE

A

Anthropometric (ht, wt, circumference, body composition), Biochemical (blood, urine, hair), Clinical (hair loss, thirst, skin pinch, discoloration), Diet (compare/contrast, self report but beware of bias), Economics/Emotions/Education

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25
Q

Know structures of D-glucose and D-fructose

A

Know em by heart. Glucose has 4 chiral centers, fructose has 3 chiral centers

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26
Q

What are anomers? How to find anomeric C?

A

alpha vs beta sugars (not D/L). Carbonyl C = anomeric C; If hydroxyl of anomeric C = down => alpha, if hydroxyl of anomeric C = up => beta

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27
Q

Pyranose vs furanose

A

6 ring (5 carbon + O) sugar, formed from aldoses vs 5 ring (4 carbon + O) sugar, formed from ketoses

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28
Q

What’s the difference b/w alpha vs beta glycosidic bonds? What type of rxn occurs to make a glycosidic bond?

A

both groups = same side vs both groups = opposite sides (A down, B up); dehydration

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29
Q

Which C’s in glucose bond to go from linear to ring? Why?

A

C5 (nuc) attacks w/ carbonyl C (electrophile) –> Carbonyl O bonds w/ H => OH group: if down => alpha, if up => beta
C5 is better because it’s thermodynamically stable. Using C4 hydroxyl would result in 5 members ring (not 6) —> less stable

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30
Q

glycosidic bonds vs N-glycosidic bonds vs O-glycosidic bonds

A

-OH group of anomeric C of monosacch reacts w/ -OH or -NH group of another cmpd vs found in nucleosides/tides vs join sugars to e/o or join sugar to -OH group of aa

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31
Q

examples of substituted sugars. know how to identify them

A

phosphate groups, amino groups, sulfate groups, N-acetyl groups, dietary disaccharides (sucrose (gluc-α-1,2-fru), lactose (gal-β-1,4-glu), maltose (glu-α-1,4-glu), and isomaltose (glu-α-1,6-glu)

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32
Q

what are glycosaminoglycan (GAG) molec? know how to recognize them

A

major constituent of proteoglycans, glycolipids, glycoproteins (they’re in extracellular matrix as shock absorbers), very charged –> inc polarity and formal neg charges –> hydrated. ex: heparin, chondroitin 4/6 sulfate, hyaluronate, dermatan sulfate, keratan sulfate

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33
Q

lipid/fat function (besides the ones mentioned in nutrition)

A

maintain body temp/insulation/heat generation by mito and electrical insulator like myelin sheath

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34
Q

know structure of fatty acids. know sat vs unsat and which config dominates in unsat

A

straight aliphatic chains w/ methyl on one end (where omega C is) and carboxyl group at other end. single C-C bonds vs double C-C bonds. cis dominates

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35
Q

examples of sat vs unsat fatty acids

A

behenic acid, arachidic acid, lauric acid, lignoceric acid, stearic acid, myristic acid, palmitic acid vs alpha linolenic acid, gamma, linolenic acid, palmitoleic acid, linolenic acid, oleic acid, arachidonic acid, nervonic acid

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36
Q

acylglycerols vs triacylglycerol (TAG) vs phosphoacylglycerols

A

glycerol backbone w/ 1+ fatty acid, fatty acid storage vs fatty acid storage, super hydrophobic, dietary fat = largely triglyceride, in liver/gut/adipose vs glycerol w/ fatty acids at C1 and C2 and phosphate at C3 (alone or w/ constituent; if phosphate alone => phophatidic acid), a type of phospholipid

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37
Q

sphingosine vs ceramide vs cerebroside vs ganglioside vs sphingomyelin

A

NO glycerol backbone –> sphingosine background (palmitate + serine; palmitate w/ amino and alc group) vs sphingosine structure but amino group is amide (thank to a fatty acid binding w/ amino group) vs 1 sugar bound to alc group vs mult sugars bound to alc group vs phosphate + N group bound to alc group

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38
Q

know how to identify cholesterol and their derivativess

A

cholesterol stabilizes cellular membranes: primarily the plasma membrane; precursors for bile salts and steroid hormones

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39
Q

know how to identify 5 nitrogenous bases and which ones are purines vs pyrimidines vs pyridines. nucleoside vs nucleotide

A

purines, double ring: A & G; pyrimidines, single ring: C, U, T; pyridines: vit B6. N-containing ring structures = reactive b/c they form H bonds
nitrogenous base, sugar (JOINED BY N-GLYCOSIDIC BOND); ex: adenosine vs nitrogenous base, sugar, 1-3 phosphate(s); ex: adenosine triphosphate

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40
Q

know names and abbrev for aa. know each category for aa. aa = major source of what?

A

aa = major source of nitrogen to synthesize all nitrogen-containing cmpds

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41
Q

the charge of aa at pH = 7.4

A

carboxyl group = deprotonated, amino group = protonated –> net zero charge w/ 1 neg and 1 pos charge => zwitterion

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42
Q

Average pKas for carboxyl vs amino groups

A

2 vs 9-10

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43
Q

List essential aa. What does it mean to be essential?

A

Very Heavy MILK is essential? - WTF –> V, H, M, I, L, K, W, T, F. we can’t synthesize it –> external diet

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44
Q

what kind of bond is peptide bond?

A

covalent amide bond; forming peptide bond = NOT SPONTANEOUS –> need enzyme to catalyze; resistant to denaturing; partial 2x bond character –> rigid and planar; uncharged but polar (ie. can do H bonds)

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45
Q

EAA deficiencies vs general protein deficiencies

A

lys = growth/development, EAA = strong antioxidants, low energy/alertness = phe -> tyr -> neurotransmitter, inc anxiety/stress = trp -> neurotransmitter vs sluggish metabolism, trouble building muscle mass, low energy and fatigue, poor concentration, muscle/bone/joint pain

46
Q

impt biomolec derived from aa

A

nitrogenous bases (gly and asp), creatine (arg and gly), glutathione (cys and glu), neurotransmitters and catecholamines (tyr), ornithine and citrulline (from arg), taurine, selenocysteine (modified ser)

47
Q

do you need enzyme to [H] or [O] cysteine?

A

yes you need enzyme to make that disulfide covalent bond

48
Q

know the 7 ionizable side chains

A

asp, glu (lower pKa) | his, cys, tyr, | lys, arg (higher pKa)

49
Q

what are the 4 weak forces? how do they relate to biomolec recognition and interaction?

A

van der Waals (weak inter-atomic attractions, depends on distance, can be electrostatic), ionic bonds (attraction b/w oppositely charged polar groups like cations and anions, salt bridge), H bonds (electrostatic dipolar interactions b/w delta pos and delta neg), hydrophobic interactions (tendency for polar molec to exclude nonpolar molec, entropy driven process, not electrostatic). ALL THESE WEAK FORCES DETERMINE PROTEIN FOLDING, MAINLY H BONDS
like dissolves like, polar seeks polar, hydrophobic seeks hydrophobic, lock and key example; weak forces restrict organisms to narrow range of environ conditions: temp, pH, ionic strength, solvent medium

50
Q

Name and describe proteins’ 4 levels of structure

A

Primary: aa seq (determined by DNA seq) stabilized by covalent peptide bonds; secondary: a helix or beta sheets stabilized by noncovalent interactions (ie. H bonds, ionic bonds, vdw interactions, hydrophobic interactions) B/W THE BACKBONE (ie. R GROUPS HAVE NOTHING TO DO WITH SECONDARY STRUCTURE); tertiary: 3D structure to show hydrophobicity/phillicity; nonrandom, ordered pathway facilitated by molec chaperone; final folded structure; quaternary: multiple subunits that can function independently or cooperatively

51
Q

3 classifications of proteins

A

globular - look like irreg balls, soluble in aq medium, fibrous - look like linear fibers, have a repeating unit structure, transmembrane - proteins that have 1+ regions aligned to cross lipid membrane

52
Q

Parallel vs antiparallel beta sheets

A

sheets running in same direction vs alternating directions; H bonds = perpendicular to polypeptide backbone; -R groups alternate b/w above and below plane for both

53
Q

super secondary structure vs domain vs motif

A

individual helices & sheets come together to form larger structures on the way towards tert structure vs part of the whole but doesn’t carry function by itself (analogy: head of body, arm of body) vs super secondary and domain structure rpted in related proteins that have similar function

54
Q

Which type of bonds help determine tert and quat structure?

A

H bonds, vdw interactions, hydrophobic interactions, ionic bonds, and disulfide bonds for tert structure; disulfide bonds create loops (ex: curly hair) AND ARE THE ONLY COVALENT BONDS

55
Q

At which structure does denaturation occur?

A

Tert —> protein loses its function. High conc of salts and detergents can denature, heat can denature. Sometimes it can affect sec and quat structures but NEVER primary —> can’t break peptide bonds

56
Q

Know that proteins go thru post-translational mods

A

enzyme-catalyzed rxns that add a chemical group, oxidize, or modify aa: glycosylations, fatty acylation/prenylation, reg modifications, [O] aa

57
Q

Hemeproteins

A

proteins that contain heme (a tightly bound prosthetic group composed of protoporphyrin IX & Fe2+); heme reversibly binds to O2 in myo/hemoglobin

58
Q

structure and function of myo vs hemoglobin

A

in heart and skel muscle, O2 reservoir w/in muscle cells, complex made of 8 alpha helices, nonpolar = interior by hydrophobic interactions and polar = on surface by H bonds w/ H2O, heme sits in b/w nonpolar groups (proximal his binds to Fe2+ of heme and distal his stabilizes the 1 O2 bound to Fe2+) vs in RBCs, transport O2 from lungs to capillaries in tissue and return CO2 and H+ from tissues to lungs, quat structure: 2 alpha helices & 2 beta sheets by noncovalent interactions

59
Q

Examples of allosteric effectors. what happens if high pH in lungs and low pH in tissues?

A

pO2, pH of environ, pCO2 (high pCO2 –> release O2), 2,3-BPG (dec O2 affinity of hgb by binding ONLY to deoxy hgb –> can’t take O2). binding of O2 to monomeric myo = not influnced by allosteric effectors. load O2 in lungs and unload O2 in tissues

60
Q

Myoglobin vs hemoglobin. Know the O2 binding curves

A

Stores oxygen, like enzyme saturation curve (hyperbolic) –> high affinity for O2 at low partial pressure [O2} than hgb; not affected by inhibitors/modulators vs transports oxygen, sigmoidal, tense state - deoxy form of hgb, rigid, hard to bind O2 & relaxed state - easy to bind to O2 —> pos cooperativity; pO2 = x axis, sat O2 = y axis

61
Q

Know high affinity vs low affinity on graph. What happens when you dec pH?

A

towards left top vs towards right bottom. Lower pH –> more p+ –> more oxygen released –> lower affinity for oxygen

62
Q

Competitive vs uncompetitive vs noncomp vs mixed inhibitors. Know what they look like graphically (ie. LINEWEAVER BURK PLOTS AND MM PLOTS)

A

competes w/ S, inc Km, (inc S does overcome inhibitor) vs binds to allosteric site of ES, dec Vmax and Km (inc S doesn’t overcome inhibitor) vs either binds to allosteric site of E or ES, dec Vmax, (inc S doesn’t overcome inhibitor) vs either binds to allosteric site of E or ES, inc/dec Km and dec Vmax

63
Q

Know the enzyme saturation graph. Know what comp and noncomp inhibition looks like on nml graph

A

x axis = [S], y axis = rxn rate

Noncomp is lower but same shape, comp has LESS steeper slope but same Vmax

64
Q

Lyases vs ligases vs hydrolases vs transferases vs isomerases vs phosphorylase vs kinase vs oxidoreductase vs dehydratase vs protease

A

cleave w/o water or e- transfer vs linking molec together w/ water removed => condensation/dehydration vs cleaves w/ water (ex: phophatase - removes phosphate group w/ water) vs transfers functional group from one molec to another vs inter conversion of isomers (ex: D to L) vs add inorganic phosphate to another molec vs transfers phosphate group typically from ATP to another molec, also a transferase v add/remove 1 or more e- to/from substrate (ex: dehydrogenase) vs removes water vs breaks peptide bond (dehydration rxn)

65
Q

What is irreversible inhibition? examples? vs non-covalent irreversible inhibitors? example?

A

When inhibitor covalently bonds w/ aa in active site —> destroys active site an enzyme permanently lost function —> need newly made enzymes to do the job; called mechanism-based inhibitor b/c they depen on nml rxn cycle for action, also can be called “suicide inhibitors” b/c enzyme does catalysis that leads to its own destruction. Acetylcholine (Ach) = neurotransmitter for synaptic transmission that’s degraded by acetylcholinesterase to terminate transmission signal; organophosphate inhibitors (nerve gas, pesticides) bind covalently to acetylcholinesterase –> destroyed. cyclooxygenase = enzyme produces prostaglandin H for pain response; ASA acetylates active site ser in cyclooxygenase –> prevents formation of prostaglandin H –> no pain (side note: acetaminophen and ibuprofen have similar structures to ASA but no acetyl group => reversible competitive inhibitors) vs inhibitors closely resembles TS –> inhibitor bind w/ such affinity that it will never dissoc from enzyme –> enzyme permanently inhibited. HIV inhibitor drugs have structure resembling TS of HIV protease = asp protease –> don’t dissoc –> no HIV proteins

66
Q

What are allosteric enzymes? Allosteric activator vs allosteric inhibitor?

A

Enzymes with active site + multiple allosteric sites. Causes shift in more available active site vs causes shift in less available active site; both of these = allosteric regulation

67
Q

As hemoglobin unloads oxygen, what happens to affinity of remaining oxygen?

A

Lowers affinity

68
Q

Enzymes stabilizes transition state —> lowers activation energy —> faster rxn rate. Once in transition state, rxn can go where?

A

Enzymes can affect kinetics (rate of chemical rxn) BUT NOT THERMODYNAMICS (ie. They don’t affect deltaG); A single enzyme doesn’t catalyze a variety of rxns cuz they’re usually highly specific. rxn can return to substrate or move forward to products –> more likely to go prod if more energetically favorable

69
Q

T/F: most enzyme-catalyzed rxns = fully reversible

A

T

70
Q

binding energy vs proximity vs induced fit vs orientation

A

binding of S to E’s active site provides binding energy –> S = closer to TS –> lowers Ea –> inc rxn rate vs binding substrates inc conc w/in active site –> inc rxn rate vs binding of S induce changes in tert structure of E => conformational change –> distort S to TS vs geometry of S binding active site allows reacting molec to be in perfect orientation for rx –> inc rxn rate

71
Q

serine protease vs chymotrypsin vs trypsin vs elastase

A

hydrolyze specific peptide bonds in proteins, mainly for digestion: made in pancreas as pro-enzymes or zymogens => inactive (they get activated when released from pancreas) vs hydrophobic binding pocket that favors aromatic residues and large nonpolar residues, Ser-OH = proximity w/ target peptide bond –> his activates ser to make nuc attack on peptide carbonyl bond –> TS –> target peptide bond cleaved but part of S = still stuck to E –> hydrolysis: E reacts w/ water (nuc) –> water attacks carbonyl C –> TS –> 2nd peptide fragment of S = released and ser = free vs deep binding pocket w/ neg charged residue (glu) at bottom that favor binding of lys and arg vs small binding pocket that favor binding of ala or gly residues

72
Q

Know the Michaelis Menton eqn and plot!!!

A

eqn: know it by heart and how to determine v after changing variables. plot: [S] = x-axis, rxn vel = y-axis, Km = [S] at half Vmax

73
Q

why regulate enzymes? how?

A

inc/dec enzyme activity to change rate of prod formation. alter [E] or alter E activity by non/covalent modulations

74
Q

noncovalent reversible binding: pos vs neg modulator

A

allosteric modulators change affinity of E for S but doesn’t change Vmax. inc affinity of E for S –> inc rxn rate at given [S], “allosteric activator” vs dec affinity of E for S –> dec rxn rate at given [S], “allosteric inhibitor”

75
Q

covalent reversible binding: kinase vs phosphatase

A

add phosphate from ATP to -OH group of S (ser, thr, tyr); phosphorylating can in/activate E (ex: glycogen phosphorylase: inactive when dephosphorylated –> when phosphorylated –> active and inc glu/dec glycogen, glycogen synthase: inactive when phosphorylated –> when dephosphorylated –> active and inc glycogen/dec glu vs removes phosphate from S by hydrolysis

76
Q

glycogen phosphorylase

A

example of allosteric modulation and reversible covalent modification; breaks gly to make G1P for glycolysis; has T and R forms; activated by AMP binding (pos allosteric noncovalent modulator) and phosphorylation (allosterically activates the E)

77
Q

regulation by protein-protein interaction and examples

A

proteins interact w/ weak interactions –> stimulate conformational change –> stimulate functional change. protein kinase A, calmodulin, G proteins

78
Q

covalent irreversible modification and examples

A

some E/proteins = made in precursor inactive forms –> proteases remove parts of precursor –> protein refolds –> E/proteins = activated (ex: proinsulin becoming insulin, chymotrypsinogen becoming chymotrypsin, Achase + organophosphate, cyclooxygenase + ASA

79
Q

regulation using isozymes and example

A

E have isoforms that catalyze same rxn –> diff regulation of enzyme in diff tissue. lactate dehydrogenase catalyzes reversible conversion of lactate to pyruvate (depends on tissue location and amount of lactate)

80
Q

minerals

A

solid, essential, inorg nutrients

81
Q

Ca2+

A

bones/teeth; 1000-1200mg/d; dairy, clams, oyster, legumes; fat malabsorption, rickets in children and osteoporosis in adults, tetany, colon ca, TIIDM, obese; hypercalcemia, calc kidney stones, heart arrhythmias

82
Q

Na+

A

extracellular cation, maintain blood vol, bp, membrane potential; 1500mg/d Na, 3800mg/d salt; muscle weakness, cramps, HA, N/V; high bp and risk for CVD

83
Q

phosphorous

A

bound to O2 in all bio systems, bone mineralization, energy transfer and storage, nucleic acid formation, acid/base balance; 700mg/d; meat, poultry, fish, eggs, legumes, nuts, cereal. renal dz, alc, diabetic ketoacidosis, resp alkalosis, starving/anorexic pts w/ refeeding syndrome; rare but renal and heart dz

84
Q

K+

A

intracellular cation, maintain membrane potential, smooth/skel/heart muscle contraction, pyruvate kinase, nutrient of public health concern; 2600mg/d F or 3400mg/d M; potatoes, tomatoes, leafy greens, beans and lentils, prune, avocado, banana; hypokalemia; hyperkalemia –> MI

85
Q

Cl

A

extracellular anion; salt, eggs, meat, seafood; electrolyte, gastric HCl acid, exchange anion; infants - loss of appetite, failure to thrive, weakness

86
Q

Mg2+

A

intracellular cation; structural cofactor, allosteric activator of enzyme activity, energy prod, structural component, cell signaling and migration, ion transport; 400mg/d M, 310mg/d F; nuts, legumes, whole grains, leafy greens; hypocalcemia, hypokalemia, N/V, sodium retention, GI d/o, renal d/o, endo/metabolic d/o; diarrhea, hypotension, lethargy, confusion, abnl cardiac rhythm

87
Q

Iron (Fe)

A

18mg/d F, 8mg/d M; heme from animal prod, non-heme from plants; iron-def anemia (fatigue, inc HR/palpitations); iron toxicity = largest cause of death in children under 6yo, GI irritation, N/V/D, constipation

88
Q

Zn

A

divalent ion (Zn2+), cofactor for collagenase and spermatogenesis; red meat, seafood, whole grains, leafy greens and roots; delayed wound healing, suppressed immune system, hypogonadism, dec in adult hair, loss of taste and smell, alc cirrhosis

89
Q

Cu

A

cofactor for cuproenzymes, energy prod, iron metabolism, connective tissue formation, CNS, melanin formation, antioxidant; organ meats, shellfish, nuts, whole grains, legumes; microcytic anemia, skel abnmlities, Menke’s syndrome (x-linked; Cu malabsorption –> inc urinary Cu loss and abnl intercellular Cu transport, dec lysyl oxidase, brittle kinky hair, growth retardation, hypotonia); Wilson’s dz (chronic liver dz, basal ganglia degeneration, Kayser-Fleischer ring around cornea, do veggie diet)

90
Q

Selenium (Se)

A

based off soil content; cofactor for glutathione peroxidase –> converts peroxide to H2O; weakness an muscle pain, loss pigmentation of hair/skin/nails, dilated cardiomyopathy; selenosis - N/V, hair/nail brittleness, paresthesia

91
Q

Iodine (I)

A

found as I-, thyroid, iodized salt; makes thyroid hormones; cretinism (poor development in children), goiter (overdevelopment of thyroid gland in adults)

92
Q

bioavailability and absorption

A

20% of Fe = absorbed from red meat, 5-10% = absorbed from plants; 50% of Ca = absorbed from food; absorption requires transport proteins in sm intestine cell membrane (ex: Fe2+ uses transport protein DCT or DMT1 –> transports Zn, Ca, Mn, Cu, Ni, Pb)

93
Q

B1

A 
thiamin; meat, legumes, grains, black bean, soy; defic: dry beriberi - chronic low thiamin intake --> muscle wasting and weakness, peripheral neuropathy, or wet beriberi - cardiovasc/myocardial issue --> cardiomegaly, rapid HR, R heart failure, peripheral edema, or Wernicke's Encephalopathy - related to alcism --> liver dmg, ophthalmoplegia, nystagmus, ataxia, loss of recent memory, confusion
thiamine pyrophosphate (TPP); used for energy transformation/metabolism (pyr dehydrog complex, alpha ketoglutarate complex)
94
Q

B2

A

riboflavin (nonpolar); dairy, legumes, meat, spinach/broccoli (***destroyed by sunlight = why milk isn’t sold in glass bottles anymore); defic: ariboflavinosis - cheilosis, corneal vascularizataion, peripheral neuropathy
e- transport to mito to drive ATP production (FAD/FMN –> FADH2/FMNH2)

95
Q

B3

A

niacin; meat, fish, legumes, peanut butter; defic: pellagra (rough skin), 4 Ds - dementia, diarrhea, dermatitis, death; tox: facial flushing/vasodilation –> take ASA, hyperglycemia, hyperuricemia
nicotinic acid and nicotinamide; for redox rxns: NAD+/NADH for catabolic rxns, NADP+/NADPH for anabolic rxns

96
Q

B5

A

pantothenic acid; plants and animals; defic: burning feet syndrome - paresthesia in toes & feet/burning in feet
forms part of coenzyme A, acyl carrier group –> acyl group attaches to sulfur

97
Q

B6

A 
pyridoxine; meat, whole grains, nuts, veggies; defic: seborrheic rash (face/neck/shoulders), weakness/fatigue, cheilosis, glossitis, angular stomatitis, confusion, peripheral neuropathy, sz & convulsions; tox: sensory & peripheral neuropathy, hyperhomocysteinemia?; use to tx: carpal tunnel, morning sickness, depression
pyridoxal phosphate (PLP coenzyme form), aa metabolism, ald group = functional center
98
Q

B7

A

biotin; colonic synthesis, meat, soybean, egg yolk, cereal; defic: aloepecia, enteritis, dermatitis
cofactor for carboxylation rxn (pyr –> oxaloacetate, acetyl CoA –> malonyl CoA in FA synthesis)

99
Q

B9

A

folate (not folic acid => synthetic); green veggies, legumes, grains, peanuts, fruit, mushrooms; defic: megaloblastic macrocytic anemia –> few large immature blood cells, fatigue, weakness, HA, irritability
tetrahydrofolate; neuro fxn, neuro development in fetus, donates methyl group in methionine synthesis, nucleic acid synthesis

100
Q

B12

A

cobalamin; animal prod –> sorry vegan/etarians, digestion requires intrinsic factor like HCl; defic: 2. Megaloblastic Macrocytic Anemia, neuro d/o methylcobalamin - transfer methyl groups, methionine synthesis; cyanocobalamin - common dietary form

101
Q

vit C

A

fruits and veggies, organ meats; defic: scurvy (Moeller-Barlow); tox: GI upset and diarrhea
ascorbic acid; made by animals from glu and gal, and plants; redox rxns

102
Q

vit A

A

retinoids: retinol, retinal, retinoic acid, retinyl ester, carotenoids: beta carotene (vit A precursor); liver, fish, dairy, carrots, sweet potato, butternut squash, cantaloupe (think yellow, orange, red food)
11-cis-retinal, vision

103
Q

vit D

A

saltwater fish, liver, beef, veal, egg yolk, dairy; defic: rickets, osteomalacia, osteoporosis; tox: bone demineralization, hypercalcemia, kidney stones
made from UVB and chol; 7-dehydrocholeterol –> cholecalciferol (D3) in animals, ergosterol –> ergocalciferol (D2) in plants and fungi

104
Q

vit E

A

plant oil, seed, nuts, peanut butter, dark leafy greens; defic: takes 5-10yrs, fat malabsorption in premature infants; least toxic vit –> can consume 100x recommended amount
antiO2, tocopherol, tocotrienol

105
Q

vit K

A

leafy greens, dairy, meat, eggs, fruit, cereal; defic: breast milk = very low, hemorrhage; tox: jaundice in infants
phylloquinone, menaquinone, “clotting” vit

106
Q

water-soluble vit vs fat-soluble vit

A

not readily stored except B12, no known toxicity vs stored in adipose –> potential for toxicity, fat absorption d/o –> fat soluble vit malnutrition

107
Q

cofactor vs metabolite vs cosubstrate vs prosthetic group vs vit

A

non-protein molec or ion require for proper functioning of enzyme vs molec produced by metabolic pathways and used by other enzymes to carry out rxns vs coenzyme bind to enzyme, carry out rxn, then dissoc from enzyme vs coenzyme bind tightly to enzyme residue at active site vs vs org, essential micronutrient

108
Q

lipoamide

A

not a B vit, it’s a prosthetic group and works w/ other vit B cofactors; formed for lipoic acid; attaches to lys of enzyme; acyl group carrier, has redox properties: ring form w/ S-S => [O] –> NAD+ -> NADH or ring form w/ -SH groups => [H]

109
Q

do MM enzymes have cooperativity? can MM enzyme be allosteric enzyme?

A

nope, only allosteric enzymes have cooperativity. nope

110
Q

protease specificity = determined by?

A

substrate binding pocket on the protease

Block 1 (20 decks)

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