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Term 1 > Biochemistry - Post Mid-term > Flashcards

Biochemistry - Post Mid-term Flashcards

1
Q

What is another name for GAG’s?

A

Mucopolysaccharides

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2
Q

What are GAG’s?

A

Long, unbranched chains of negatively charged sugars

* Repeating disaccharide units

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3
Q

What are proteoglycans?

A

Many GAG’s linked to a protein chain

95% sugar, 5% protein

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4
Q

What is a proteoglycan monomer?

A

Central core protein

* Many disaccharide units linked via trihexoside bond

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5
Q

Are GAG’s positively or negatively charged?

A

Negative – contributes to the bottle-brush structure (slippery mucus + synovial fluid)

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6
Q

Which of the GAG’s is NOT sulfated?

A

Hyaluronic acid

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7
Q

Where is hyaluronic acid synthesized?

A

Integral plasma membrane protein (other GAG’s in the rER)

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8
Q

What is a proteoglycan aggregate?

A

Long, central strand of hyaluronic acid & proteoglycan monomers

  • NOT covalently bound
  • Use link proteins
  • Aggregate can function as shock absorber
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9
Q

Where is proteoglycan aggregate assembled?

A

Extra-cellular space

* Proteoglycans synthesized intracellularly

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10
Q

What is found at position 1 & 2 of GAG disaccharides?

A

1: acid sugar (glucuronic or iduronic acid)
2: amino sugar (N-acety-amino sugar)

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11
Q

Where are most GAG’s found?

A

Extracellularly

EXCEPT: Heparin – found in mast cells lining the lungs, liver & skin

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12
Q

Who is sulfated more: heparin or heparan sulfate?

A

Heparin

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13
Q

A deficiency of GAG’s can lead to:

A

OA

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14
Q

What is the function of heparin?

A

Anti-coagulant

* Can prevent clotting during surgery

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15
Q

What is warfarin?

A

Synthetic vitamin K; slower acting than heparin

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16
Q

Describe the synthesis of a proteoglycan monomer.

A
  1. Core protein enters rER
  2. Protein O-glycosylated @ serine by glycosyl transferases in Golgi
  3. Trihexisode linkage (xylose, galactose, galactose) formed & UDP-glucuronic acid and UDP-amino sugars used to synthesize disaccharide units
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17
Q

Who sulfates GAG’s?

A

PAPS (phospho-adenosyl-phospho-sulfate)

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18
Q

Why is sulfation of GAG’s important?

A

Make the GAG’s even more negatively charged

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19
Q

A defect in sulfation can lead to…

A

Chondrodystrophy (disorder of development and maintenance of skeletal system)

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20
Q

Which GAG is unsulfated?

A

Hyaluronic acid

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21
Q

What is a glycoprotein?

A

90% protein; 10% sugar (attached in O- or N- glycosylation)

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22
Q

Where is hyaluronic acid found?

A

Synovial fluid
Vitreous humor of eye
* Shock absorber, lubricant (not covalently attached to protein)

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23
Q

Which 2 GAG’s are found in cartilage?

A

Chondrotin sulfate

Keratin sulfate

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24
Q

Where is dermatin sulfate found?

A

Skin, vessels, heart valves

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25
Q

Where is heparan sulfate found?

A

Basement membranes (more acetylated glucosamine than heparin)

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26
Q

Where is keratan sulfate found?

A

Cartilage, bone, cornea

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27
Q

Where is chondriotin sulfate found?

A

Cartilage, bone, heart valves

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28
Q

Which is the most abundant GAG?

A

Chondrotin sulfate

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29
Q

Which plasma protein is not a glycoprotein?

A

Albumin

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30
Q

What are the functions of glycoproteins?

A

Cell surface recognition, antigen presenters, mucins

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31
Q

What are mucins?

A

Glycoproteins with 80% sugars

  • Long protein core, negatively-charged NANA or sialic acid linked to amino sugars
  • Attract water; resistent to proteolysis by digestive enzymes
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32
Q

Are the sugars in blood group proteins N- or O-linked?

A

O-linkage at serine or threonine residues

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33
Q

Describe O-glycosylation

A

Step-by-step linkage of activated sugarts

* First sugar linked to -OH group (serine or threonine or hydroxylysisne during procollagen synthesis)

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34
Q

Describe why O-glycosylation is special for collagen synthesis.

A

Sugar linked to -OH group of hydroxylysisne during procollagen synthesis

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35
Q

What is the only exception to the O-glycosylation rule?

A

Self-glycosylation of tyrosine residue performed by glyocgenin during glycogen synthesis

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36
Q

Describe N-glycosylation

A

Does not individually link sugars directly to the protein chain

  • Uses dolichol-PP
  • Sugar precursor attached to N of ASPARAGINE
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37
Q

N-glycosylated proteins can contain…

A
  1. Complex oligosaccharides

2. High-mannose

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38
Q

Can glutamine be involved in N-linked glycosylation?

A

NO - only asparagine

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39
Q

Which lipid is used as a precursor for N-glycosylation?

A

Dolichol-PP

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40
Q

How many mannose residues are found in the finished sugar precursor in N-linked glycosylation?

A

9

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41
Q

Complex N-glycosylation proteins include:

A

N-acetylglucosamine, NANA, L-fucose

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42
Q

In what form is activated mannose during N-glycosylation?

A

GDP-mannose

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43
Q

Which are the X-linked lysosome storage diseases?

A

Hunter disease

Fabry disease

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44
Q

Are lysosomal enzymes O- or N- glycosylated?

A

N – mannose-6-p

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45
Q

Which enzyme is deficient in the sphingolipidoses Tay Sachs, Fabry, Gaucher and Niemann-Pick Disease, metachromatic leukodystrophy, respectively?

A 
Tay Sachs Disease:  hexosaminidase A
Fabry Disease: alpha-galactosidase
Gaucher Disease:  glucocerebrosidase
Niemann Pick Disease: sphingomyelinase 
Metachromatic: aryl sulfatse
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46
Q

Which compounds accumulate in Tay Sachs, Gaucher, Fabry, Niemann-Pick Disease, & metachromatic leukodystrophy, respectively?

A

Tay Sachs Disease: GM2
Gaucher Disease : glucocerebrosides
Fabry Disease: globosides (ceramide trihexoside)
Niemann-Pick Disease Type A and B: sphingomyelin
Metachromatic: sulfatide

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47
Q

Describe the differences between Niemann-Pick Disease Type A and Type B.

A

A: infantile, deadly
B: late childhood onset - no neurodegen

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48
Q

What is the most common lysosomal storage disorder?

A

Gaucher

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49
Q

What is a sphingolipid?

A

Lipid with sphingoside alcohol

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50
Q

What is a ceramide?

A

Sphingosine + fatty acid

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51
Q

What are 2 types of sphingolipids?

A
  1. Glycosphingolipids (Ceramide + carb)

2. Spingophospholipids (sphingomyelin) (Ceramide + phosphorylcholine)

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52
Q

The enzyme required for lipolysis is

A

Hormone sensitive lipase

Active when phosphorylated – epinepherine

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53
Q

The first enzyme in the activation of fatty acids is:

A

Thiokinase (fatty acyl coA synthetase)

* Requires 2 ATP

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54
Q

The 2 enzymes and shuttle required to transport fatty acyl coA across the mito membrane…

A

CPT1 (inhibited by malonyl-CoA – product of TAG synthesis)
CPT2
Carnitine shuttle

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55
Q

Who inhibits CPT1?

A

Malonyl CoA (product of TAG synthesis)

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56
Q

The 4 steps of beta-oxidation of fatty acids

A
  1. Oxidation - FAD - MCAD
  2. Hydration
  3. Oxidation - NAD+
  4. Cleavage
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57
Q

A 16 C fatty acid will be broken into…

A

8 acetyl CoA’s
7 FADH
7 NADH

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58
Q

An MCAD deficiency results in:

A

Fasting hypoglycemia
Hypoketosis
Increase serum fatty acids
Increase dicarboxylic acids in urine

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59
Q

Jamacian vomiting sickness is a result of eating an unripe ackee fruit…

A

Hypoglycin A (MCAD inhibitor)

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60
Q

Oxidation of odd-chain FA’s requires 2 cofactors

A

Biotin (proprionyl coA carboxylase) & B12 (methylmalonyl coA mutase)

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61
Q

This syndrome results from defective peroxisomal biogenesis…

A

Zellweger syndrome

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62
Q

This sydrome results from inability to metabolize branched chain FA’s (alpha-oxidation)

A

Refsum disease (phytanyl coA alpha-hydroxylase)

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63
Q

This is a small pathway of FA oxidation (and its product can be elevated w/ a beta-oxidation deficiency)

A

Omega-oxidation (dicarboxylic acids)

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64
Q

The 3 enzymes required for ketogenesis are…

A
  1. Tholase (acetoacetyl coA)
  2. HMG coA synthase (HMG coA)
  3. HMG coA lyase (acetoacetate)
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65
Q

Which enzyme of ketogenesis is also used in cholesterol synthesis?

A

HMG coA synthase (cytosol-cholesterol; mito-ketogenesis)

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66
Q

For the utilization of ketone bodies, the key enzyme is:

A

Thiophorase (NOT present in liver)

Acetoacetate –> acetoacetyl coA

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67
Q

DKA results from

A 
Inadequate insulin (more likely in DM1)
* Acetone breath from excessive ketogenesis
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68
Q

Name the two main sites of fatty acid de novo synthesis in humans.

A
  1. Liver

2. Lactating mammary gland

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69
Q

Where does fatty acid synthesis take place within the cell?

A

Cytoplasm

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70
Q

What are the 2 essential (dietary) fatty acids?

A
  1. Omega-6: Linoleic acid

2. Omega-3: alpha-linolenic acid

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71
Q

Who is the precursor to arachidonic acid?

A

Omega-6, linoleic acid

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72
Q

When is fatty acid synthesis likely to occur?

A

After a high carbohydrate meal

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73
Q

Which metabolic condition leads to high citrate levels in liver mitochondria?

A

High carbohydrate diet

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74
Q

What is the fate of increased citrate?

A

Trasported to the cytosol

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75
Q

What enzyme & co-factors are necessary for the reaction citrate –> acetyl coA?

A

ATP, coA

  • Enzyme: citrate lyase
  • Occurs in cytosol
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76
Q

Which enzyme in the mitochondria is inhibited by high levels of ATP during fatty acid synthesis?

A

Isocitrate DH

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77
Q

What are the 4 methods to generate acetyl coA in the mitochondria?

A
  1. PDH

2. Degradation: FA, ketone bodies, AA’s

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78
Q

Describe the cellular location and the reaction catalyzed by the malic enzyme!

A
  • Liver cytosol
    Oxaloacetate –> Malate –*–> Pyruvate
  • Generates NADPH
  • Irreversible reaction
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79
Q

What is the rate-limiting enzyme for fatty acid synthesis?

A

ACC (acetyl-coA carboxylase)

Acetyl CoA –> malonyl CoA

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80
Q

What 3 cofactors does acetyl coA carboxylase require?

A

Biotin, CO2, ATP

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81
Q

What 2 molecules can be used to carboxylate acetyl coA to malonyl coA?

A
  1. CO2

2. Bicarbonate (HCO3-)

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82
Q

In what form is acetyl coA carboxylase active/inactive? Who promotes allosteric activation/inactivation?

A

Active: polymer>dimer (CITRATE)
Inactive: dimer>polymer (PALMITOYL COA)

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83
Q

Describe the allosteric, hormonal & long-term activation of ACC.

A
  • Polymerized-form
    1. Citrate
    2. Insulin (de-phosphorylates)
    3. High carb, low fat diet
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84
Q

Describe the allosteric, hormonal & long-term inactivation of ACC.

A
  • Dimer-form
    1. Palmitoyl coA / long chain fatty acyl coA’s
    2. Glucagon, NE/E (phosphorylates - cAMP)
    3. High fat diet, fasting, glucagon
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85
Q

Which form of FAS is active?

A

Dimer

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86
Q

What is the name of the multifunctional enzyme that catalyzed 7 different reactions in fatty acid synthesis?

A

FAS (fatty acid synthase)

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87
Q

The synthesis of palmitate from malonyl coA requires…

A

14 NADPH

7 ATP

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88
Q

How many carbons are in malonyl coA?

A

3 C

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89
Q

Briefly describe the process of palmitate synthesis from malonyl coA?

A

2 arms: acetyl coA (sulfhydrl) condensing arm added to the ACP (acyl carrier peptide) arm which has malonyl coA (CO2 released)

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90
Q

What are 2 typical modifications of palmitate, once formed? Where does these modifications occur?

A
  1. Chain elongation (ER – add malonyl CoA’s or mito – reversal beta-oxidation)
  2. Desaturation at C’s 5, 6, 9 (ER)
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91
Q

What makes linoleic & alpha-linolenic acid essential?

A

They have double bonds beyond C # 9

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92
Q

Name 2 ways to form NADPH.

A
  1. PPP

2. Malic enzyme (malate –> pyruvate)

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93
Q

Glucose is to glycogen, as fatty acids are to:

A

TAG

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94
Q

Why is palmitoyl CoA the feedback inhibitor of ACC & not palmitate?

A

Palmitate has detergent character to cell membranes

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95
Q

Where in the human cell are long chain fatty acids elongated, in the FA synthase complex or in the ER or in mitochondria? Where in the cell are fatty acids desaturated? Which enzyme is involved?

A

In humans, fatty acids are elongated and desaturated in the ER using their activated form as fatty acyl CoA.

The enzyme involved in desaturation contains cytochrome b5.

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96
Q

Is docosahexaenoic acid (DHA 22:6, 3) synthesized in humans from linoleic acid, from -linolenic acid, or from arachidonic acid? Why is DHA so important?

A

DHA is synthesized in humans from linolenic acid3 family.

Linoleic acid (18:2) and arachidonic acid (20:4) are of the 6 family and cannot be used.

DHA is needed in the fetus and infants for brain and visual development and later
on in adults for general brain metabolism.

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97
Q

List the 4 major sites of TAG synthesis in humans.

A
  1. Liver
  2. Fat
  3. Lactating mammary gland
  4. Intestinal mucosa
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98
Q

Discuss 2 ways glycerol-3-phosphate can be formed.

A
  1. Glycerol –glycerol kinase–> glycerol-3-p

2. DHAP –NADH–> glycerol-3-phosphate

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99
Q

Why is TAG synthesis in the intestinal mucosa cells simplified?

A

TAG –panc lipase–> MAG –2 acyl coA–> DAG, TAG (no need for phosphatidyl intermediate)
* Necessary b/c intestinal mucosa cells have to resythesize a large amount of dietary TAG’s

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100
Q

What is unique about TAG synthesis in the liver?

A

Can pick up free glycerol in the blood (glycerol kinase) –> glycerol-3-phosphate

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101
Q

What is the intermediate in TAG synthesis in the liver & fat?

A

Lysophosphatidic acid

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102
Q

Desaturation of fatty acids requires:

A
  1. Cytochrome B5
  2. Desaturase
  3. NADPH-cytochrome B5 reductase
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103
Q

Which fatty acid is generally used to synthesize eicosanoids?

A

Arachidonic acid (precuror: Linoleic acid - omega-6)

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104
Q

How many carbons in an eicosanoid?

A

20

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105
Q

What cells DO NOT synthesize eicosanoids?

A

RBC’s

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106
Q

Which cell type synthesizes mainly prostacyclin and which cells synthesizes mainly thromboxane?

A

Prostacyclin: endothelial cells
Thromboxane: platelets

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107
Q

Which phospholipase can be used for direct release of arachidonic acid out of phospholipid membranes?

A

Phospholipase A2 (cleaves FA in position 2 of the glycerol backbone)

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108
Q

Which hormone inhibits the release of arachidonic acid by inhibition phospholipase A2?

A

Cortisol (glucocorticoid)

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109
Q

How can eicosanoids act?

A

Locally

  1. cAMP
  2. PLA2 (inc. Ca)
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110
Q

Describe the relationship between phospholipase C, PIP2, IP3 & DAG

A

PLC cleaves PIP2 to generate IP3 & DAG

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111
Q

Within the cell, arachidonic acid resides at _____ postion of the membrane phospholipids.

A

C-2

* Hence, PLA2 cleaves phosphatidylinositol

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112
Q

Who cleaves PIP2 to generate arachidonic acid?

A

PLA2

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113
Q

NSAID’s

A

COX-1 & COX-2 inhibtors

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114
Q

Cortisol

A

PLA2 + COX-2 inhibitor

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115
Q

Celecoxib

A

Celebrex (selective COX-2 inhibitor)

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116
Q

Which NSAID is an IRREVERSIBLE inhibitor of COX?

A

Aspirin

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117
Q

Who promotes COX-2?

A

Cytokines, endotoxin, tumor promotors, growth factors

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118
Q

Differentiate between COX-1 & COX-2.

A

COX-1

  • Constiutive, all tissues
  • Normal physio fx: gastric secretion, renal blood flow, homeostasis

COX-2

  • Non-constituitive (liver, macrophages) in response to immune response
  • Increased prostaglandin synthesis –> PAIN, HEAT, REDNESS, HEAT, SWELLING, FEVER
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119
Q

Induction of COX-2 results in:

A

Pain, heat, redness, swelling, fever

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120
Q

Aspirin reversibly/irreversiby in COX by…

A
  1. Irreversibly

2. Acetylating a serine residue in the active site

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121
Q

Differentiate between TXA2 & PGI2

A

TXA2: vasoconstriction/platlet aggregation
PGI2: vasodilation/decreased platlet aggregation

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122
Q

The 2 effects of 81 mg aspirin:

A
  1. Reduced TXA2 synthesis (dec clotting)

2. NO significant effect on PGI2

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123
Q

To overcome the irreversible inhibition by low dose aspirin…

A

Synthesize more COX

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124
Q

Why does low dose aspirin not affect prostaglandin, but affect thromboxane?

A

Prostagland - vascular endothelium (can synthesize more COX1)
Thromboxane - eunucleated platlets – must wait 7-10 days before NEW platlets are synthesized

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125
Q

Who is responsible for bronchoconstriction?

A

Thromboxane

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126
Q

How might dietary fish oil prevent inflammation?

A

Omega-3 –> EPA –> TXA3 & PGI3 (reduced clotting)

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127
Q

The immediate precursors to PGI2 & TXA2 are:

A

PGG2 –> PGH2

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128
Q

Leukotrienes are secreted during…

A

Allergic/hypersensitivity reactions

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129
Q

Who uses LTA?

A
  • Mast cells

- Eosinophils

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130
Q

LTA –> LTC?

A

Addtion of the tripeptide glutathione

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131
Q

Who are the cysteine-leukotrienes?

A

LTC, LTD, LTE

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132
Q

LTC, LTD, LTE …

A

Increase vascular permeability, and lead to severe bronchoconstriction, vasoconstriction & lung edema

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133
Q

The enzyme responsible for leukotriene synthesis:

A

lipoxygenase

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134
Q

3 possible treatments for asthma:

A
  1. Steroids / inhibit release arachidonic acid
  2. Lipoxygenase inhibitor
  3. Cysteinyl-leukotriene receptor antagonists
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135
Q

Would you expect COX-2 in platlets?

A

COX-2 synthesis is induced. Protein synthesis is not possible in platelets and therefore one would not expect COX-2 in platelets.

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136
Q

What is the effect of low dose apirpin on COX?

A

COX-1 on platelets – unable to synthesize thromboxane

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137
Q

What is the function of prostaglandins?

A
  1. Gastric protection (+ mucus, - acid)

2. Renal BP regulation

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138
Q

Compare the 2 to the 3 series of PG & TX.

A

PGI2 = PGI3
TXA2 > TXA3
* Hence, a diet rich in omega-3’s will favor prevetion of blood clotting due to weaker TXA3

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139
Q

Why will a diet a diet rich in omega-3’s favor prevention of blood clotting?

A

Weaker TXA3

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140
Q

Name the intermediate that is formed in the linear pathway from arachidonic acid in the synthesis of leukotriene A4.

A

5-lipoxygenase forms 5-HPETE

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141
Q

LBTB4 …

A

acts mainly as chemo-attractant for neutrophils in blood

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142
Q

LTC4 lead to…

A

Severe bronchioconstriction

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143
Q

Name the components of the slow reacting substance of anaphylaxis (SRS-A). Is SRS-A stronger or weaker than histamine?

A

SRS-A contains LTC, LTD and LTE. It is much more potent than histamine.

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144
Q

Which molecule is linked to LTA4 in order to form LTC4?

A

Tripeptide glutathione

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145
Q

Why are LTC, LTD and LTE named cysteinyl-leukotrienes?

A

All contain covalently bound a cysteinyl-group that originated in glutathione.

146
Q

Describe the anti-inflammatory action of glucocorticoids related to inhibition of release of arachidonic acid.

A

Corticosteroids inhibit the release of arachidonic acid by inhibition PLA2 & also COX-2

147
Q

Compare the actions of PGE to PGF2

A

Vasoconstriction is performed by PGF 2

Vasodilation is performed by PGE2

148
Q

Name four major functions or usages of cholesterol!

A

a. Cholesterol modulates the correct fluidity of the plasma membranes
b. Cholesterol is used only in the liver for synthesis of primary bile acids
c. Cholesterol is used for steroid hormone de novo synthesis only in the adrenal cortex, ovaries and testes.(not in the liver)
d. An intermediate of cholesterol synthesis is used in the skin for the formation of vitamin D (process needs UV light)

149
Q

In which cells does cholesterol synthesis mainly take place? In which cell compartment? Why are mitochondria needed?

A

Cholesterol synthesis takes place mainly in the hepatocyte and in cells of the adrenal cortex and in the brain.

  • Takes place in cytosol; mito needed for citrate (citrate lyase)
150
Q

What are the 3 major sources of liver cholesterol?

A
  1. Diet
  2. Lipoproteins (HDL, LDL)
  3. De novo synthesis
151
Q

The liver sends cholesterol 3 places. What are they?

A
  1. Secrete in HDL/VLDL
  2. Free cholesterol in bile
  3. Bile salts/acids
152
Q

What percentage of dietary fat is cholesterol?

A

10% (Majority is TAG’s)

153
Q

The key regulated enzyme in cholesterol synthesis…

A

HMG CoA reductase

154
Q

HMG CoA reductase is regulated by…

A

Negative: glucagon, AMP kinase, high cholesterol diet, cholesterol, statins
Positive: insulin

155
Q

HMG CoA reductase is activated when phosphorylated/dephosphorylated

A

Dephosphorylated

156
Q

Cholesterol has how many C’s?

A

27

157
Q

The side products of cholesterol synthesis are…

A
  1. Dolichol & Ubiquinone (IPP & FPP)

3. Protein prenylation (GPP & FPP)

158
Q

Why are so many pyrophosphates needed in cholesterol synthesis?

A

Necessary to make the intermediates soluble in the cytosol

159
Q

What is the location of the key enzyme of cholesterol synthesis?

A

ER membrane-bound

160
Q

What is the paradox associated with statin use?

A

Statins reduce the amount of cholesterol produced by competitively inhibiting HMG CoA reductase
* The decreased cholesterol paradoxically causes upregulation of the enzyme (by release of SREBP, which binds to SRE region of HMG coA reductase gene & increases transcription)

161
Q

HMG CoA reductase is regulated by intracellular/extracellular cholesterol.

A

Intracellular cholesterol

162
Q

What is the acronym for the protein released when intra-cellular cholesterol is low?

A

Sterol regulatory element binding protein (SREBP)

163
Q

Who activates SREBP?

A

SCAP

164
Q

Statins have 4 major effects

A
  1. Increased LDL receptor on cell surface
  2. Increased uptake of LDL from serum
  3. Decreased serum cholesterol
  4. Increased HMG CoA reductase transcription – SREBP (paradox)
165
Q

In the liver, a high concentration of cholesterol…

A

Leads to degradation of HMG CoA reductase by the ubiquination system in proteasomes

166
Q

Low intracellular cholesterol leads to…

A
  1. Upregulation of LDL receptors

2. Synthesis of cholesterol

167
Q

Which enzyme promotes the storage of cholesterol esters?

A

ACAT

168
Q

SLOS (Smith Lemli Opitz Syndrome)

A
  • Auto recessive cholesterol synthesis problem
  • Deficiency of 7-dehydrocholesterol reductase
  • X double-bond formation, ring B, partially deficient
169
Q

The difference between Hunter syndrome & Hurler syndrome

A

Mucopolysaccaridoses

  • Hurler: iconidase
  • Hunter: iconidate
  • Both lead to build-up of dermatin & keratin sulfate
  • Hunter –> no occular problems
170
Q

True/False. Cholesterol can be metabolized by humans

A

False – ring structure cannot be metabolized

171
Q

Elimination of cholesterol

A

Cholesterol –> Bile acids –> Feces

172
Q

Cholesterol is modified by intestinal bacteria to form…

A
  1. Cholestanol

2. Coprostanol

173
Q

The rate limiting enzyme of bile acid synthesis is: (mention products & regulation)

A

7-alpha-hydroxylase

  • Products: cholic acid & chenodeoxycholic acid
  • +: cholesterol
  • -: cholic acid
174
Q

What is the difference between bile acids & bile salts?

A

Bile salts are bile acids conjugated with glycine or taurine.
* Bile salts are much more effective at solubilizing lipids than bile acids

175
Q

What are the 2 major bile salts?

A
  1. Glycocholic acid/glycochenodeoxycholic acid

2. Taurocholic acid/Taurochenodeoxycholic acid

176
Q

The major organic components of bile…

A
  1. Phosphatidylcholine (lecithin)

2. Bile salts

177
Q

What is the fate of bile salts & acids?

A

97% are recycled by portal circulation

178
Q

The action of intestinal flora on bile salts…

A
  1. Remove taurine/glycine

2. Convert primary bile salts into secondary bile salts by removing hydroxyl (deoxycholic acid & lithocholic acid)

179
Q

Cholelithiasis is caused by…

A
  1. Deficiency of lecithin (phosphatidylcholine) &/or bile salts
    * Causes cholesterol in bile to precipitate in the gall bladder
180
Q

The difference between cholesterol gallstones vs. black pigment gallstones

A

Chol: cholesterol

Black pigment: bilirubinate (less common)

181
Q

4 treatments for cholelithiasis

A
  1. Surgery
  2. Chenodeoxycholic acid (chenodiol)
  3. Shock wave disintegration
  4. Contact exposure methyl-tert-butyl ether
182
Q

If a gallstone obstructs the ampulla of Vater…

A

Acute pancreatitis

183
Q

What are the 4 functions of bile acids?

A
  1. Excretion of cholesterol in feces
  2. Solublize cholesterol (prevent precipitation in bile)
  3. Emulsify dietary TAG’s for pancreatic lipase
  4. Intestinal absorption of fat-soluble vitamins (ADEK)
184
Q

Who are the 4 fat-soluble vitamins?

A

A, D, E, K

185
Q

What is the difference between primary and secondary bile salts?

A

Secondary bile salts are de-conjugated (glycine & taurine) & de-hydroxylated
* deoxycholic acid + lithocholic acid

186
Q

Many ____ coenzymes are used in cholesterol synthesis.

A

NADPH

187
Q

What is the broad concept of cholesterol synthesis?

A

The concept is to form a five-carbon building block that is used six times to form
a 30 carbon molecule.

188
Q

What is the 5-carbon building block of cholesterol synthesis & how is it formed?

A

isopentenyl-PP (IPP). It is formed by

decarboxylation of mevalonyl-PP.

189
Q

Lipoproteins contain a phospholipid monolayer/bilayer?

A

Monolayer (mostly PC)

190
Q

What is needed for the appropriate function of lipoproteins?

A

Apo-lipoproteins

191
Q

Chylomicron release from intestinal mucosal cells requires…

A

Apo B-48

192
Q

VLDL release by the liver requires…

A

Apo B-100

193
Q

In order to be taken up by the liver, IDL’s & chylomicron remnants require…

A

Apo E

194
Q

VLDLS are cleaved to… What is the fate of these molecules?

A

IDL’s by LPL

* 50% to the liver; 50% cleaved by HTLG to LDL

195
Q

What is the difference between hepatic lipase and lipoprotein lipase?

A

LPL – capillaries of heart, adipocytes

Hepatic lipase – capillaries of liver

196
Q

What is the fate of LDL’s?

A

70% to the liver

30% extra-hepatic – steroid synthesis, cell membranes

197
Q

An unfortunate consequence of high serum LDL…

A

oxLDL –> invade macrophages via SR-A1 –> foam cells

198
Q

3 risk factors for coronary heart disease (with respect to LDL)

A
  1. Foam cells
  2. LDL-pattern B (smaller / can be trapped in ECM)
  3. LP (A)
199
Q

What is Lp (a)?

A

Covalently bound (disulfid bond) to apo-B-100

  • Structural analog to plasminogen & can compete with plasminogen for binding to fibrin
  • Reduce removal of blood clots & could trigger MI/Stroke
200
Q

How do the various lipoproteins separate using gel electrophoresis after a fast?

A
  1. Chylomicrons stay at origin (s travel furthest
201
Q

Abnormal lipoprotein metabolism can be divided into…

A
  1. Hyperlipidemia
    - -HyperTAG – 1, 4, 5
    - -HyperChol – 2, 3
  2. Hypolipidemia
    - -Hypoalphalipoproteinemia
    - -Abetalipoproteinemia
202
Q

Hypertriacylglycerolemias lead to … (serum)

A

TAG blood values

203
Q

What is the difference between Hyperlipidemia I, IV, V

A

I: chylomicrons (a-LPL; b-APO C-2; c-LPL inhibitor)
IV: VLDL (common) (LPL deficiency)
V: VLDL & chylomicrons

204
Q

What is the difference between hyperlipidemia 2 & 3?

A

2A- Familial hypercholesterolemia - defective LDL receptor - elevated LDL
2B- elevated LDL & VLDL
3 - dysbetalipoproteinemia - high remnants (IDL & chylo remnants)
Homo - APO E-2 – less effective (E rhymes with 3)

205
Q

Statins can be used to treat …

A

Hyperlipidemia 2A

206
Q

Differentiate between statins & bile acid sequesterants…

A

Statins – competitive inhibitors of HMG CoA reductase (inc LDL receptor syn & paradoxically increase HMG CoA reductase transcription)
Bile acid sequesterants – excrete bile acids/salts in feces; liver makes more, thus lowering cholesterol

207
Q

What does the liver use cholesterol for?

A

Synthesis of bile salts/acids

208
Q

4 major components of bile

A
  1. Conjugated bile salts
  2. PC
  3. Free cholesterol
  4. Conjugated bilirubin
209
Q

T/F There is a storage form of nitrogen in humans

A

False

210
Q

What are the 3 ways to contribute to the amino acid pool in the body?

A
  1. Protein synthesis / turnover
  2. Dietary
  3. AA synthesis (non-essential)
211
Q

What area the 2 major ways AA’s are used in the body?

A
  1. Catabolism (urea, C-skeleton)

2. Synthesis of N-containing compounds

212
Q

What are several N-containing compounds?

A

Heme, creatine, neurotransmitters, purines, pyramidines

213
Q

What are the dietary essential amino acids?

A 
P-phenylalanine
V-valine
T-threonine
T-tryptophan
I-isoleucine
M-methionine
H-histadine
A-argininine
L-leucine
L-lysine
214
Q

Which are the 3 conditional non-essential amino acids?

A
  1. Cysteine (methionine)
  2. Tyrosine (phenylalanine)
  3. Arginine
215
Q

What are the 2 major methods of protein degradation?

A
  1. Lysosome (extra-cellular/cell-surface proteins)

2. Proteasome/ubiquitination – proteins syn. by cell

216
Q

What are the 4 ways proteins are turned over in the body?

A
  1. Oxidative damage
  2. Denaturation - hydrophobic core exposed
  3. Ubiquination - ATP dept.
  4. PEST (proline, glutamate, serine, threonine) sequences – short 1/2 life
217
Q

T/F Ubiquination is an ATP dependent process

A

True

218
Q

What is the fate of ubiquitin post-proteasome?

A

Recycled

219
Q

What can result from an inappropriate release of lysosome components from WBC’s into the joints?

A

Inflammatory disease

220
Q

What is the pH environment of the lysosome?

A

Acidic

221
Q

Where do most AA’s release their amino groups as ammonia?

A

Liver

222
Q

What is the fate of NH3?

A

Detoxified to urea

223
Q

What are amino acid carbon skeletons used for?

A
  1. GNG

2. Burned in TCA cycle

224
Q

Urea made in the liver is transported to the __________ for excretion.

A

Kidney

225
Q

How can the kidneys excrete ammonia as ammonium ions?

A

Glutamine (glutaminase ion)

226
Q

What are 2 examples of non-protein nitrogenous substances excreted by the kidney?

A
  1. Uric acid (purine degrad)

2. Creatinine (creatine degrad)

227
Q

What is the major nitrogenous product excreted in the urine?

A

Urea (86%)

228
Q

Describe the reaction: glutamine –> glutamate + NH4+

A

Glutaminase (kidney)

229
Q

How are amino acids absorbed at the intestinal brush border?

A

Secondary active transport

Na/K gradient; portal vein w/ own gradient

230
Q

What is one major cause of renal stones in children?

A 
Cystinuria (COAL)
C- cystine
O- ornithine
A- arginine
L- lysine
* Cystine excreted and urine, can precipitate & cause stones
231
Q

What disease results from a defect in transport of neutral amino acids, i.e. tryptophan?

A

Hartnup’s disease

* Can result in NAD+ deficiency (pellagra)

232
Q

From what amino acid do you synthesize NAD+?

A

Tryptophan

233
Q

What disease results from the lack of NAD+?

A

Pellagra

234
Q

Tissue protein catabolism results in …

A

Amino acids (amino group off, or to anthoer alpha-keto acid)
2. Alpha keto acid
3 & 4 – pyruvate/glucose (glucogenic); acetyl coA (ketogenic)

235
Q

Differentiate between:

Essential vs. Non-essential AA
Glucogenic vs. Ketogenic AA

A

Essential: cannot be synthesized by human
Glucogenic: substrates for GNG (pyruvate) or TCA intermediate
Ketogenic: acetoacetate, acetyl CoA, acetoacetyl CoA

236
Q

What are the 2 major ketogenic AA’s?

A

Leucine, Lysine (acetoacetyl-CoA)

237
Q

What 2 AA’s can be used to make alpha-ketoglutarate?

A

Glutamate, glutamine

238
Q

What types of amino acids can be used to make succinyl coA?

A

BCAA’s (isoleucine, valine)

239
Q

What 2 AA’s can be used to make fumerate?

A

Phenylalanine, tyrosine

240
Q

What two amino acids can be used to make oxaloacetate?

A

Asparagine, aspartate

241
Q

What AA can be used to make pyruvate?

A

Alanine

242
Q

What enzyme catalyzes the reaction involving alanine?

A

Alanine -ALT + B6-> Pyruvate

* Amino group transferred to alpha-ketogluterate to form glutamate

243
Q

The glucose-alanine cycle involves what two organs?

A

Muscle (form pyruvate) & liver (GNG)

244
Q

The major transport AA during starvation…

A

Alanine

245
Q

Is the reaction between alanine & ALT reversible?

A

Yes

246
Q

What enzyme is often used for the treatment of leukemia?

A

Asparaginase (reduced availability of asparagine inhibits tumor growth)

247
Q

3 enzymes are capable of incorporating free ammonia.

A
  1. Glutamate DH
  2. Glutamine synthetase
  3. CPS I
248
Q

Where is glutaminase active?

A

Renal tubule/liver

249
Q

Where is glutamine synthetase active?

A

BRAIN & endothelial cells of the hepatic vein

250
Q

Which enzyme is particularly helpful in picking up free ammonia in the brain?

A

Glutamine synthetase

251
Q

The reversible reaction in glutamate metabolism…

A 
Glutamate DH (liver-oxidation)
Reverse reaction (uses free ammonia) to make glutamate
252
Q

The enzyme Glutamate DH requires…

A

NAD+

253
Q

The enzyme AST requires…

A

PLP (B6)

254
Q

The metabolism of aspartate…

A

Aspartate –> Asparagine (asparagine synthetase – uses free glutamine, not ammonia)

255
Q

The 3 major disorders of Phe/Tyrosine metabolism:

A
  1. PKU 1 (PAH), Maternal, 2 (malignant - BH2 reductase) – mousey urine
  2. Alkaptonuria – homogentisic acid oxidase – dark urine
  3. Tyrosinemia – cabbage urine – fumerylacetoacetate hydrolase
256
Q

The 2 major disorders of branched chain AA deficiency…

A
  1. MSUD - branched chain alpha-ketoacid DH (+ B1) – ketosis + maple syrup urine
  2. Methylmalonic aciduria (methylmalonyl CoA mutase + B12) – seizures, encepholapthy
257
Q

What is homocystinuria?

A

Cystathione beta-synthase deficiency

* Disruption of C/T (collagen!) – osteoporosis, lipid deposits

258
Q

What are the 2 fates of homocystein?

A
  1. Recycled to methionine

2. Sulfur delivered to serine to form cysteine

259
Q

Transamination reactions require…

A

PLP (Vitamin B6)

260
Q

How is NH3 transported from peripheral tissues?

A
  1. Glutamine

2. Alanine

261
Q

Transamination reactions, in general, use this as an amino acceptor…

A

Alpha-ketogluterate

262
Q

What is the fate of urea from the liver?

A

75% - kidney

25% - gut / ureases & proteases

263
Q

The urea cycle has 2 N donors

A
  1. Glutamate (ammonia)

2. Aspartate

264
Q

Where does the urea cycle take place?

A

Liver (1 & 2 - mitochondria; 3-5 - cytosol)

265
Q

The major regulated enzyme of the urea cycle.

A

CPSI (requires NAG n-acetyl glutamate)

266
Q

N-acetylglutamate (NAG) formation can be stimulated by…

A

Arginine

267
Q

For which congenital hyperammonemia disorder is it not kosher to give arginine?

A

Arginemia

268
Q

The 5 enzymes required for the urea cycle:

A
  1. CPSI (NAG)
  2. OTC
  3. ASS
  4. ASL
  5. ARG
269
Q

Treatment for hyperammonemia (congenital)

A
  1. Dialysis
  2. Benzoic acid (benzyl CoA -glycine-> hippurate)
  3. Phenylbutyrate –> phenylacetate –> phenylacetylglutamine
  4. Low protein diet
270
Q

Acquired hyperammonemia

A
  • Porto-systemic shut of ammonia

- Neurotoxicity

271
Q

3 treatments for acquired hyperammonemia

A
  1. Low protein diet
  2. Lactaluslose (produces lactic acid – can be neutralized by NH4+)
  3. Neomycin (antibiotic that can reduce bacterial urease in the gut)
272
Q

What is an antibiotic that can reduce gut urease activity?

A

Neomycin

273
Q

What are the 2 prevailing hypotheses related to neurotoxicity secondary to hyperammonemia?

A
  1. Energy (taking up TCA intermediates alpha-KG –> glutamate)
  2. Neurotransmitter (decreased GABA & glutamate)
274
Q

Parkinson’s Disease

A
  • Loss of dopamine producing cells in basal ganglia
  • Admin: L-dopa (with a dopa decarboxylase inhibitor)
  • Neurodegenerative movement disorders
275
Q

Serotonin is synthesized in…

A

Gut, platelets, CNS

276
Q

Pheochromocytoma

A

Elevated VMA & catecholamines (urinary)

  • Episodic – headache, thirst, tachy
  • Adrenal medulla tumor
277
Q

Synthesis of serotonin

A

Tryptophan -BH4-> 5 hydroxytryptophan -AA decarboxylase-> serotonin

278
Q

The phenylalanine cascade…

A

Phe -PAH-> Tyr -TH-> L-DOPA -decarboxylase-> DOPAMINE -hydroxylase-> NE -SAM/methylate-> Epi

279
Q

The degradation of catecholamines

A
  • MAO & COMT (catechol o-methyl transferase)
    • Dopamine –> HVA (homovanillyic acid)
    • NE/E –> VMA (vanillyl acid)
280
Q

Dopamine beta-hydroxylase requires…

A

Vitamin C

281
Q

DOPA decarboxylase requires…

A

Vitamin B6 (PLP)

282
Q

Carcinoid

A
  • Tumor of serotonin producing cells in GIT
  • Cutaneous flushing, diarrhea
  • Increased 5-HIAA excretion in urine
283
Q

From what is melatonin derived?

A

Serotonin

284
Q

The 3 reactions requiring BH4 coenzyme

A
  1. Phe -> Tyrosine
  2. Tyr –> L-DOPA
  3. Tryptophan –> 5-hydroxytryptophan
285
Q

A deficiency of BH4…

A

Can result in delayed mental development + seizures

- Treat with Neurotransmitter precursors in diet + dietary Phe restriction

286
Q

A tetrahydrobiotin deficiency can manifest from a deficiency of 2 enzymes

A
  1. BH2 reductase

2. BH2 synthesis

287
Q

How is GABA synthesized?

A

Glutamate -decarboxylase + PLP-> GABA

288
Q

How is histamine produced?

A

Histidine -decarboxylase + PLP->

289
Q

The major inhibitory neurotransmitter…

A

GABA

290
Q

What is the GABA shunt?

A

GABA –> TCA cycle

291
Q

Histamine is a vasocontrictor/dilator

A

Dilator

292
Q

In general, how do anti-histamines work?

A

Receptor antagonists

* Not enzyme inhibitors **

293
Q

2 popular examples of anti-histamines

A

H1 (benadryl), H2 (Zantac) blockers

294
Q

From whom is creatine synthesized?

A

Arginine, Glycine & SAM

295
Q

Where is creatine found?

A

Muscle, heart, brain

296
Q

What is creatine?

A

Reservoir of high energy-bonds

  • Accepts phosphate during rest
  • Donates phosphate during contraction
297
Q

What enzyme modulates the transition of creatine to creatine phosphate?

A

Creatine kinase (CK, CPK)

298
Q

NO is synthesized from which AA & which enzyme?

A

Arginine (NO mARG!)

* NO synthase (releases cirtulline)

299
Q

What can be used as a vasodilator during an MI?

A

Nitroglycerin

300
Q

Where is NO synthesized?

A

Endothelium of blood vessels

* Causes vasodilation

301
Q

The NO cascade…

A

Guanylate cyclase –> cGMP –> relaxation vessels –> phosphodiesterase

(Second messenger cascade)

302
Q

What is melanin?

A

A polymer of pigmented molecules derived from tyrosine

303
Q

The enzyme deficiency in albinism?

A

Tyrosinase (tyrosine –> melanin)

304
Q

The more severe form of albinism

A

Occulocutaneous albinism

305
Q

The tripeptide glutathione is composed of:

A

GCG

  • glutamate
  • cysteine
  • glycine
306
Q

Glutathione acts as an anti-oxidant by:

A

H202 –> H20 (reduced); GSH –> GSSG (reduced)

* Important for integrity of cell membrane

307
Q

The 2 reactions that require vitamin B12

A
  1. Methionine synthase (homocysteine –> methionine)

2. Methylmalonyl coA mutase

308
Q

The 4 AA’s that can be used by the odd-chain FA oxidation

A
  1. Methionine
  2. Isoleucine
  3. Valine
  4. Threonine
309
Q

Methionine synthase requires 2 vitamins

A
  1. B12

2. B9 (folic acid – methylated-THF)

310
Q

Lack of intrinsic factor will result in…

A 
Pernicious anemia (inability to take up B12)
* B9 will be tied up methylated and anemia will result
311
Q

Vitamin B9 is referred to as

A

Folic acid

312
Q

T/F Proks can synthesize B9

A

TRUE

313
Q

What are 2 drugs that involve folic acid?

A
  1. Methotrexate (competitive inhibitor of dihydrofolate reductase)
  2. Sulfonamides (Dihydropterin synthase in proks from PABA)
314
Q

Sulfonamides

A

Competitively inhibit dihydropterin synthase in proks from PABA (make folic acid)

315
Q

Glycine & Serine can be interconverted using

A

B9 (folic acid) & serine hydromethyl transferase

316
Q

The dihydrofolate reductase reaction requires

A

2 NADPH

317
Q

How do we get from histidine to flutamate?

A

FIGlu (donates formino group to folate)

* Deficiency in folate will result in elevated FIGlu

318
Q

How do you test for folic acid deficiency?

A

FIGlu levels

319
Q

Folic acid is generally used for…

A

1 carbon transfer reactions (DNA/RNA synthesis), degradation of histadine, regeneration of methionine, serine glycine

320
Q

A common B12 & folic acid deficiency can lead to

A

Megaloblastic anemia

321
Q

Difference between NE & Epi

A

NE - nervous system

Epi - functions like a hormone

322
Q

Difference between epinepherine & cortisol

A

Cortisol - GNG

Epi – glycogenolysis

323
Q

Which amino acid promotes both insulin & glucagon release?

A

Arginine

324
Q

Glucagon release is stimulated by these amino acids

A

Arginine, alanine

325
Q

Insulin release is stimulated by these amino acids…

A

Arginine, leucine

326
Q

Isoniazide

A

Can deplete the body of PLP (B6)

* Used for treatment of TB

327
Q

Heme is used in…

A

Hemoglobin, cytochrome ETC, NO synthase, Catalase

328
Q

Difference between heme synthesis in liver vs. bone marrow

A

Liver: inhibited by heme/hemein (product inhibited)
Erythroid: limited by Fe availability

329
Q

Lead

A

Messes with ALADH & Zn-cofactors in ferrochelatase

330
Q

Photosensivity will result once this compound accumulates…

A

HMB (hydromethylbilane)

331
Q

Which enzymes of heme synthesis are in the mitochondria?

A

ALAS1/2, Ferrochelatase

332
Q

5 porphrias

A
  1. ALAS2 (X-linked sideroblastic anemia)
  2. ALADH (Hereditary ALADH deficiency)
  3. HMB Syn/PDA (Acute intermittent porphyria)
  4. Congenital EPO porphyria (Uro synthase – serious)
  5. Porphyria Cutanea Tarda (Uro DC – often due to chronic liver disease)
333
Q

What might you not treat someone with who has porphyria?

A

Barbituates (can stimulate cytomchrome p450 formation)

334
Q

Difference between direct & indirect bilirubin

A 
Direct = conjugated with gluconaric acid
Indirect = unconjugated (with albumin)
335
Q

Crigler-Najjer I, II & Gilber’s disease

A

Varying levels of severity of the UDP-gluconryl transferase enzyme

336
Q

Dubin Johnson Syndrome

A

Deficient ABC transporter of bilirubin into the bile

337
Q

Jaundice occurs when serum bilirubin is > ____

A

2 mg/dL

338
Q

What hormone does adipose produce?

A

Leptin * Appetite supressor

339
Q

What is the difference between Type 1, 2A/B muscle fibers?

A

1 - red - slow twitch, rich capillary supply, decreased glycogen storage

340
Q

Which AA’s are synthesized from glucose?

A

Glutamate, Aspartate, Glycine

341
Q

What is the GABA shunt?

A

GABA is recycled in the CNS

* Glutamate is synthesized de novo in the brain from BCAA

342
Q

How is acetylcholine synthesized?

A

Requires choline from the diet

PE + methyl -SAM, THF, B12-> acetylcholine

343
Q

Vitamin B1

A
  1. PDH
  2. Alpha-KG DH
  3. BCAA DH
344
Q

Which cytochrome p450 is important in ethanol metabolism?

A

CYP2E1

  • In chronic alcoholics, acetaminophin is processed more by CYP2E1 –> toxic compound
  • NAPQ1 –> ROS/can lead to cell death
345
Q

What can Acetaminophin poisioning in a chronic alcoholic be treated with?

A

Acetadote (N-acetyl-cysteine)

346
Q

Describe the metabolism of alcohol.

A

ETOH -ADH-> Acetaldehyde -ALDH1(c)2(m)-> Acetate

  • NADH produced, ALDH1 active at high ETOH concentrations & also MEOS (CYP2E1) more active
347
Q

Describe the effects of chronic alcoholism

A

High NADH:NAD – unanble to carry out GNG, accumulation of lipids and fats in the liver (fatty liver)

348
Q

Describe poisoning with methanol & ethylene glycol.

A

Both are substrates for ETOH DH.

  • Can lead to formaldehyde & glycoaldehyde/oxalate
  • Treat with ETOH or Fomepizole
  • Requires bicarb/hemodialysis
349
Q

Describe the effects of grapefruit ingestion while a patient is on statins.

A

Grapefruit inhibit CYP3A4 (required for statin control)

* A patient on statins who eats grapefruit regularly can have liver damage

350
Q

Describe the relationship between Warfarin & Phenobarbital

A

Warfarin unduces CYP3A4 & Phenobarbital inactivates it

* Suddenly taking a patient off of phenobarbital can lead to massive bleeding

351
Q

Describe LFT’s

A

B- bilirubin
P- proteins (albumin, clotting factors, etc.)
M- metabolites (ammonia, glucose)
E- enzymes (AST, ALT, GGT, ALP)

352
Q

Describe the pre-beta, beta, and alpha serum protein bands

A

pre-beta: VLDL

beta: LDL
alpha: HDL

353
Q

Describe the alpha-1 proteins

A

A1-Antitrypsin
AFP (alpha-fetoprotein) – elevated in HCC/testicular/ovarian cancer (mothers-low in Downs, high in spina bifida)
Transcortin (cortisol)
RBP (retinol)

354
Q

Describe the band separations on serum protein electrophoresis.

A

Albumin, A-1, A-2, beta (includes CRP), gamma

355
Q

Describe the alpha-2 proteins

A

Alpha-2-macroglobulin
Ceruloplasmin (Cu / also helpful in Fe metabolsim)
Haptoglobin (free Hb)

356
Q

Describe the beta proteins

A

Transferrin
Hemopexin
Beta-lipoprotein

357
Q

Describe the difference between serum and plasma

A

Serum – no clotting factors (let blood clot, centrifuge & take the supernatant) – preferred analysis

Plasma – includes clotting factors – need to have an anti-coagulant in the blood

358
Q

Describe the gamma globulins

A
  • Synthesized by plasma cells
  • IgG - most abundant (mother–> fetus)
  • IgM - infection
  • IgE - allergy
  • IgA - body secretions
  • IgD - unknown
359
Q

Which acute phase protein is released during inflammation? It is included in what band?

A

CRP (beta-globin)

360
Q

Describe the platelet plug formation

A

G1A – binds to collagen
G1B – VWF binds to this on the platlet
G2B/3A – allows binding of fibrinogen

Term 1 (10 decks)

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