Term
| A patient with Aldolase B deficiency would have problems tolerating what sugar? |
|
Definition
|
|
Term
| What enzyme, unique to the liver, is crucial to fructose metabolism in the liver and what does it turn fructose into? |
|
Definition
| FRUCTOKINASE; Fructose-1-Phosphate |
|
|
Term
| What is the action of Aldolase B? |
|
Definition
| Breaks F-1-P into Glyceraldehyde and Dihydroxyacetone |
|
|
Term
| What is the fate of Glyceraldehyde from Aldolase B? |
|
Definition
| It can be phosphorylated (via Triose Kinase) into Glyceraldehyde-3-P, a glycolysis intermediate |
|
|
Term
| What is the fate of Dihydroxyacetone? |
|
Definition
| It is already a glycolysis intermediate |
|
|
Term
| If a patient cannot metabolize fructose, what enzyme is deficient and what are the consequences? |
|
Definition
Aldolase B- liver glycolysis and gluconeogenesis are deficient
HYPOGLYCEMIA |
|
|
Term
| What happens to fructose in most non-liver cells? |
|
Definition
| It gets phosphorylated directly to Fructose-6-Phosphate |
|
|
Term
| What does high glucose do to hexokinase action in shunting fructose to glycolysis? |
|
Definition
|
|
Term
| What happens when Fructose-1-P builds up? |
|
Definition
This is Aldolase B deficiency;
Glycogen breakdown is inhibited |
|
|
Term
| Why do lactate levels increase in Aldolase B deficiency? |
|
Definition
| Gluconeogenesis is inhibited, so no Pyruvate conversion |
|
|
Term
| So, again and again, what do we see in Aldolase B deficiency? |
|
Definition
| Hypoglycemia; high lactate; low ATP |
|
|
Term
| A patient with galactosemia would have what principle clinical symptom? |
|
Definition
|
|
Term
| What enzyme is deficient in non-classical galactosemia? |
|
Definition
|
|
Term
| What enzyme is deficient in classical galactosemia? |
|
Definition
| Galactose-1-P uridylyltransferase |
|
|
Term
| What two compounds are the primary products of the pentose phosphate pathway? |
|
Definition
|
|
Term
| What primary reducing agent is made by the pentose phosphate pathway? |
|
Definition
|
|
Term
| What vitamin is critical to the non-oxidative portion of the pentose phosphate pathway? |
|
Definition
|
|
Term
| What vitamin is deficient in alcoholics and causes a breakdown in the pentose phosphate pathway? |
|
Definition
|
|
Term
| What is the only source of NADPH for the red blood cells? |
|
Definition
| Pentose Phosphate Pathway |
|
|
Term
| How many NADPH are produced in the oxidative phase of the pentose phosphate pathway? |
|
Definition
| TWO- for antioxidant action and other reduction reactions |
|
|
Term
| What is the effect of thiamine deficiency in alcoholics on the pentose phosphate pathway? |
|
Definition
|
|
Term
| What is the major enzyme that converts 5C molecules to 6C molecules after the PPP to reenter glycolysis, and what vitamin is required? |
|
Definition
|
|
Term
| What are two important consequences of thiamine deficiency? |
|
Definition
| Anemia, increased oxidative stress |
|
|
Term
| Nigerian med student develops hemolytic anemia after taking primaquine (anti-malarial). Why? |
|
Definition
| GLUCOSE -6-P DEHYDROGENASE DEFICIENCY |
|
|
Term
| If a patient has G-6-P Dehydrogenase deficiency, they don't produce NADPH to act on what enzyme that converts oxidized glutathione? |
|
Definition
|
|
Term
| Primaquine, in patients with G-6-P Dehydrogenase deficiency, causes a reduced amount of what important compound? |
|
Definition
| NADPH, primary reducing agent |
|
|
Term
| What enzyme gets rid of peroxide? |
|
Definition
|
|
Term
| What is the primary mechanism of hemolysis in hemolytic anemia? |
|
Definition
|
|
Term
| What is the name of the complex formed from oxidized glutathione and metHemoglobin? |
|
Definition
|
|
Term
| What is the prominent antioxidant mechanism in red blood cells? |
|
Definition
|
|
Term
| What reaction converts superoxide and peroxide into oxygen, water, and hydroxyl radical? |
|
Definition
|
|
Term
| What reaction breaks hydrogen peroxide into hydroxyl radical and hydroxyl ion, using Fe? |
|
Definition
|
|
Term
| What does oxidative stress from free radical damage do to membranes? |
|
Definition
|
|
Term
| What is the main mechanism by which cell membranes are damaged by reactive oxygen species? |
|
Definition
|
|
Term
| Patients with a deficiency in what enzyme should not eat Fava beans? |
|
Definition
| G-6-P Dehydrogenase (Favism) |
|
|
Term
| What is the compound in Fava beans that is dangerous to people with G-6-P Dehydrogenase deficiency, and what does it do? |
|
Definition
| DIVICINE; increases oxidative stress by producing H2O2 |
|
|
Term
| True or False: Fatty acids can be used to synthesize glucose? |
|
Definition
FALSE- WE NEVER USE FA's TO MAKE GLUCOSE
Ketone bodies, yes. Glucose, NEVER. |
|
|
Term
| Once glycogen stores are depleted, what becomes the MAJOR source of fuel? |
|
Definition
|
|
Term
| What is the main source of energy for gluconeogenesis in the renal medulla? |
|
Definition
|
|
Term
| Glucagon activates which protein kinase? |
|
Definition
|
|
Term
| What 3 steps of glycolysis are irreversible everywhere but in the liver? |
|
Definition
Glucose to G-6-P
Fructose 6-P to Fructose 1,6 bis P
Phosphoenolpyruvate to Pyruvate |
|
|
Term
| What is the difference between hexokinase and glucokinase? |
|
Definition
Hexokinase- everywhere but liver, non regulated
Glucokinase- liver- MUST BE ACTIVATED BY INSULIN |
|
|
Term
| What enzyme is deficient in Von Gierke's Disease, and what is the consequence? |
|
Definition
| Glucose-6-Phosphatase, glucose cannot be released |
|
|
Term
| What enzyme converts fructose 1,6,P to fructose 6-P? |
|
Definition
| Fructose Bisphosphatase (turned on by glucagon) |
|
|
Term
How many ATP are produced by glycolysis?
How many ATP are consumed by gluconeogenesis? |
|
Definition
|
|
Term
| What enzyme that produces Lactate regenerates NAD for glycolysis? |
|
Definition
| Lactate Dehydrogenase (anaerobic) |
|
|
Term
| Where does all of glycolysis take place? |
|
Definition
|
|
Term
| How does oxaloacetate leave the mitochondria? |
|
Definition
| Shuttled as either Malate or Aspartate |
|
|
Term
| What conversion reaction in the mitochondria is mediated by BIOTIN, and what enzyme catalyzes the reaction? |
|
Definition
| Pyruvate to Oxaloacetate; Pyruvate Carboxylase |
|
|
Term
| The conversion of pyruvate back to phosphoenolpyruvate requires what vitamin as a cofactor, and is regulated by what hormones? |
|
Definition
| BIOTIN; turned on by glucagon and off by insulin |
|
|
Term
| Starting with lactate, which vitamin is needed in gluconeogenesis that is not needed in glycolysis? |
|
Definition
| BIOTIN, for reverse step from pyruvate back to phosphoenolpyruvate |
|
|
Term
| What is the result of the Cori cycle? |
|
Definition
| Sythesis of glucose in the liver |
|
|
Term
| What is the primary source of carbons for gluconeogenesis? |
|
Definition
|
|
Term
| In what form do amino acids leave the TCA cycle? |
|
Definition
|
|
Term
| What are the two ketogenic amino acids? |
|
Definition
| Leucine and Lysine; pvt tim haLL |
|
|
Term
| What is unique about the ketogenic amino acids? |
|
Definition
| They cannot synthesize glucose; they can only make ketone bodies |
|
|
Term
| The last step of gluconeogenesis utilizes glucose-6-phosphatase. Where does this take place? |
|
Definition
| In the Endoplasmic Reticulum |
|
|
Term
| In determining whether the action of glucagon or insulin dominates, what is most important? |
|
Definition
| The GLUCAGON to INSULIN RATIO |
|
|
Term
| What two processes get energy from proteins? |
|
Definition
| Gluconeogenesis and ketone body synthesis |
|
|
Term
| Why does the blood concentration of fatty acids stabilize in the fasting state? |
|
Definition
| Limitations of solubility and the protein carrier (albumin) |
|
|
Term
| What is the major energy source 8 hours into a fast? |
|
Definition
|
|
Term
| What is the major energy source 24 hours into a fast? |
|
Definition
| Still glycogen, but the majority is depleted and gluconeogenesis is beginning to dominate |
|
|
Term
| What is the major energy source 3 days into a fast? |
|
Definition
|
|
Term
| What molecule is the precursor for proteoglycans, glycoproteins, synthesis of galactose, and other cellular carbohydrates? |
|
Definition
|
|
Term
|
Definition
| A precursor for metabolizing things in the liver that are not very soluble- VERY WATER SOLUBLE- important in liver metabolism (glucaronide) |
|
|
Term
| What molecule is the main way that we get rid of heme in the liver? (hint: think of CONJUGATED...) |
|
Definition
| Glucuronate, to make bilirubin diglucuronide (Conjugated Bilirubin= SOLUBLE) |
|
|
Term
| What two molecules are required for the synthesis of lactose in the mammary gland? |
|
Definition
| UDP-galactose and free glucose |
|
|
Term
| What bond holds the monosaccharides of lactose together, and what are those monosaccharides? |
|
Definition
| B1-4 glycosidic; Galactose and Glucose |
|
|
Term
| What are glycosylate d proteins? |
|
Definition
| Tags- like license plates- sugars are attached to proteins in the smooth ER |
|
|
Term
| What is Dolicol Phosphate? |
|
Definition
| A 5C Isoprenoid ANCHOR on which oligosaccharides are constructed |
|
|
Term
| What drug inhibits the synthesis of Dolicol Phosphate? |
|
Definition
|
|
Term
| How are sugar groups transfered to proteins? |
|
Definition
|
|
Term
| To what amino acid residue of a glycoprotein does dolicol attach oligosaccharides? |
|
Definition
|
|
Term
| What is an oligosaccharide? |
|
Definition
|
|
Term
| What happens if there is a deficiency in the mannose tag of a lysosomal enzyme? |
|
Definition
| Mannose normally phosphorylates to Mannose-P- if this does not happen, it does not bind to its receptor and the enzyme never gets to the lysosome |
|
|
Term
| What happens in I-cell disease? |
|
Definition
The lysosomal enzymes don't get glycoprotein tags and never end up in the lysosome
-The lysozome has no function, and continues to grow empty of enzymes until it gets so big that it LYSES the cell |
|
|
Term
| Sorting of enzymes and proteins in the Golgi Apparatus depends on what? |
|
Definition
| TAGS made of oligosaccharides |
|
|
Term
| What is the difference between type O blood and types A and B? |
|
Definition
Type O blood has no Galactose OR GalNAc
Antigenic tag- ONLY H SUBSTANCE |
|
|
Term
| What is the difference between Type A and Type B blood? |
|
Definition
Type A blood has GalNAc tag
Type B blood has Galactose tag |
|
|
Term
| What enzyme is defective in Tay Sachs disease, and what does this cause? |
|
Definition
Hexosaminidase A, which removes GalNAc
-defect of digestive enzymes in lysosome |
|
|
Term
| What enzyme is defective in Fabry's disease? |
|
Definition
|
|
Term
| What enzyme is defective in Gaucher's disease? |
|
Definition
|
|
Term
| What enzyme is defective in Neimann-Pick Disease? |
|
Definition
|
|
Term
|
Definition
|
|
Term
| What is the action of penicillin? |
|
Definition
| Prevents the synthesis of peptide cross links in peptidoglycan |
|
|
Term
| Name 3 repeating disaccharides: |
|
Definition
| Hyaluronate; chondroitin; keratan sulfate |
|
|
Term
|
Definition
| A protein with a repeating dissacharide |
|
|
Term
| What is a proteoglycan aggregate? |
|
Definition
| Like hyaluronate- a glycan with proteoglycans- a large, bushy, water-absorbent complex that has lots of sugars and cushions joints |
|
|
Term
| How many psychiatrists does it take to change a lightbulb? |
|
Definition
| Only one, but the lightbulb has to want to change :) |
|
|
