What Do You Know About Carbohydrates? Quiz

25 Questions | Total Attempts: 147

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What Do You Know About Carbohydrates? Quiz

Carbohydrates are sugars that can be found in most of the foods we consume, and they play a major role in especially when it comes to brain function and energy. Even when one is on a diet, they can’t avoid carbohydrates. What do you know about Carbohydrates? Take up the quiz below and get find out now more about these important sugars.


Questions and Answers
  • 1. 
    A healthy 34 year old male demonstrates normal blood glucose levels after 12-hours of fasting.  Which of the following reactions contributes most to the observed finding?
    • A. 

      Glycogen-Glucose-1-phosphate

    • B. 

      Acetyl CoA-Palmitate

    • C. 

      Oxaloacetate -phosphoenolpyruvate

    • D. 

      Fructose 6-phosphate-Frutose 1.6-bisphosphate

    • E. 

      Acetoacetyl Coa-3 Hydroxy-3-methylglutaryl CoA

  • 2. 
    In certain metabolic conditions, hepatocytes increase the conversion of glucose to ribulose-5-phosphate.  This conversion most likely supplements which of the following?
    • A. 

      Energy production

    • B. 

      Glycogen storage

    • C. 

      Ketone body synthesis

    • D. 

      Cholesterol synthesis

    • E. 

      Protein degradation

    • F. 

      Uric acid production

  • 3. 
    A 12 year-old male presents to your office complaining of poor exercise tolerance.  He describes muscle cramps on physical activity, especially after intense straining.  He also describes urine discoloration that happens after strenuous activities.  Further testing reveals that exercise tolerance can be greatly improved in this patient if glucose solution is infused during exercise.  Which of the following substrate flow pathway is most likely deficient in this patient?
    • A. 

      A

    • B. 

      B

    • C. 

      C

    • D. 

      D

    • E. 

      E

  • 4. 
    A 30 year-old female is diagnosed with Hashimoto’s thyroiditis and subsequently started on thyroid-replacement therapy.  Which of the following is true about thyroid hormones?
    • A. 

      They act by activation of tyrosine kinase

    • B. 

      They act primarily by activation of adenylyl cyclase

    • C. 

      They have a nuclear receptor

    • D. 

      They have a cytoplasmic receptor.

    • E. 

      They act by increasing the activity of phosphlipase C

  • 5. 
    A 3 month-old male is being evaluated for muscle hypotonia and feeding difficulties.  Physical examination reveals hepatomegaly and severe cardiomegaly.  Muscle biopsy shows polysaccharide accumulation within lysosomes.  Which of the following enzymes is most likely deficient in this patient?
    • A. 

      Glucose-6-phosphatase

    • B. 

      Glycogen phosphorylase

    • C. 

      Acid α-glucosidase

    • D. 

      Debrancher enzyme

    • E. 

      Galactokinase

    • F. 

      Pyruvate kinase

  • 6. 
    Some transmembrane receptors employ Janus Kinase (JAK) to stimulate enzymes in the cytoplasm.  Which of the following substances is most likely to utilize this pathway?
    • A. 

      Insulin

    • B. 

      Platelet-derived growth factor (PDGF)

    • C. 

      Growth hormone

    • D. 

      Atrial natriuretic peptide

    • E. 

      Progesterone

    • F. 

      Gamma- aminobutyric acid (GABA)

  • 7. 
    An agent that specifically blocks the interaction of inositol triphosphate with its intracellular receptor would most likely decrease the activity of:
    • A. 

      Phospholipase C

    • B. 

      Lipoxygenase

    • C. 

      Protein kinase C

    • D. 

      Phosphodiesterase

    • E. 

      Adenylate cyclase

  • 8. 
    A 44 yea-old homeless male develops confusion and ophthalomoplegia.  Upon review of the medical record, you discover that he has been admitted to the hospital with alcohol intoxication several times before.  Which of the following reaction is most likely impaired in this patient?
    • A. 

      A

    • B. 

      B

    • C. 

      C

    • D. 

      D

    • E. 

      E

    • F. 

      F

    • G. 

      G

  • 9. 
    A 34-year-old female develops moderate hyperglycemia during her first pregnancy and is diagnosed with gestational diabetes mellitus.  Her glycemic status improves markedly after delivery.  She says that her mother and younger sister both have “high blood sugars” during pregnancy.  If this patient’s gestational hyperglycemia is genetically predisposed, this patient is most likely to have decreased activity in which of the following enzymes?
    • A. 

      Glucokinase

    • B. 

      Phosphofrutokinase

    • C. 

      Aldolase

    • D. 

      Pyruvate kinase

    • E. 

      Enolase

    • F. 

      Pyruvate cardoxylase

    • G. 

      Lactate dehydrogenase

  • 10. 
    A 64 year-old male hospitalized with severe abdominal pain and hypotension beings to hyperventilate.  Laboratory testing reveals metabolic acidosis, an increased anion gap and high plasma lactate level.  This patient’s findings are best explained by a low activity of:
    • A. 

      Pyruvate kinase

    • B. 

      Lactate Dehydrogenase

    • C. 

      Pyruvate dehydrogenase

    • D. 

      Pyruvate carboxylase

    • E. 

      Enolase

  • 11. 
    A 3 year-old male suffers from chronic diarrhea, greasy stool and anemia.  This patient is significantly underweight.  He has mild edema of the lower extremities and oral ulcers.  Parenteral feeding and vitamin supplementation are started in this patient.  Pantothenic acid is necessary for which of the following conversions in this patient’s metabolism?
    • A. 

      Glucose to pyruvate

    • B. 

      Glucose to ribose-5-phosphate

    • C. 

      Alanine to glucose

    • D. 

      Oxaloacetate to citrate

    • E. 

      Glutamate to a ketoglutarate

  • 12. 
    A group of investigators studies the intracellular mechanisms of signal transduction.  In a series of experiments, they demonstrate that pretreatment with tumor necrosis factor alpha (TNF-alpha) result in decrease insulin-mediated glucose uptake.  TNF-alpha causes a defect in which of the following processes?
    • A. 

      CAMP hydrolyzation

    • B. 

      Phosphatidylinositol cleavage

    • C. 

      Stimulation of peroxisome proliferator activated receptor

    • D. 

      Serine residue phosphorylation

    • E. 

      Proline residue hydroxylation

  • 13. 
    A sample of liver parenchyma is homogenized and centrifuged to remove  membrane components and organelles leaving only the cytosol and the proteins it contains.  Which of the following enzyme activities is most likely present in the homogenate?
    • A. 

      Pyruvate carboxylase

    • B. 

      Ornithine transcarbmoylase

    • C. 

      Transketolase

    • D. 

      Succinate dehydrogenase

    • E. 

      3-Hydroxy-3-merhylgutaryl-CoA lyase

  • 14. 
    Binding of GTP to a membrane-associated protein causes rapid metabolic changes in hepatocytes.  These effects include a decrease in intracellular glycogen stores and the release of glucose into blood.  Which of the following is the most likely mediator responsible for these effects?
    • A. 

      CGMP-dependent protein kinase

    • B. 

      Tyrosine-specific protein kinase

    • C. 

      Protein kinase A

    • D. 

      Phosphodiesterase

    • E. 

      Janus tyrosine kinase (JAK)

  • 15. 
    Monosaccharide delivered to the liver may have different rates of intracellular metabolism.  Which of the following substance has the highest rate of metabolism in the glycolytic pathway?
    • A. 

      Glucose-6-phosphate

    • B. 

      Mannose-6-phosphate

    • C. 

      Galactose 1-phosphate

    • D. 

      Fructose 1-phosphate

    • E. 

      Glucose 1-phosphate

  • 16. 
    Liver cells that demonstrate a high concentration of fructose 2,6-biphosphate have a low rate of which of the following conversions?
    • A. 

      Glucose → glycogen

    • B. 

      Acetyl CoA → fatty acids

    • C. 

      Alanine → glucose

    • D. 

      Pyruvate → oxaloacetate

    • E. 

      α-Ketoglutarate → glutarnate

  • 17. 
    An infant who is apparently healthy at birth is diagnosed with aldolase B deficiency two weeks later.  Which of the following should be removed from this patient’s diet?
    • A. 

      Lactose

    • B. 

      Sucrose

    • C. 

      Maltose

    • D. 

      Amylose

    • E. 

      Cellulose

  • 18. 
    An infant born to 22 years-old female experiences lethargy, vomiting and jaundice soon after birth.  The infant is places on a galactose - free formula and shows gradual improvement.  Which of the following steps in galactose metabolism is most likely impaired in this patient?
    • A. 

      A

    • B. 

      B

    • C. 

      C

    • D. 

      D

    • E. 

      E

  • 19. 
    An apparently healthy 23 year-old male is found to excrete large amounts of fructose in his urine.  Despite this patient’s defect in fructose metabolism, dietary fructose can still participate in glycogen synthesis in this patient due to the activity of:
    • A. 

      Hexokinase

    • B. 

      Fructokinse

    • C. 

      Aldolase B

    • D. 

      UDP-hexose 4-epimerase

    • E. 

      Aldose reductase

  • 20. 
    A 78 year-old female suffers from nausea, anorexia, fatigue, and skin rash on her legs.  She is mildly demented and is believed to have severe malnutrition.  Laboratory findings include an organic aciduria.  You suspect that biotin deficiency may contribute to this patient’s symptoms.  Which of the following conversions is impaired in those with biotin deficiency?
    • A. 

      Pyruvate to alanine

    • B. 

      Pyruvate to oxaloacetate

    • C. 

      Glucose to ribose-5-phosphate

    • D. 

      Pyruvate to acetyl-CoA

    • E. 

      Succinate to oxaloacetate

  • 21. 
    An infant suffering from severe neurological symptoms and lactic acidosis with pyruvate dehydrogenase complex deficiency.  When placed on a special diet, the patient demonstrates some decrease in the blood lactate level.  Which of the following substances can be most safely supplemented to this patient?
    • A. 

      Glycerol

    • B. 

      Alanine

    • C. 

      Galactose

    • D. 

      Lysine

    • E. 

      Asparagine

    • F. 

      Serine

  • 22. 
    A 6 month-old male is brought to the ER with recent onset vomiting, irritability and jaundice.  The infant was born at term and has been apparently healthy until the onset of these symptoms.  All of his vaccinations are up-to-date.  He has been exclusively breast-fed until one week ago when cereals and fruit juices were introduced into his diet.  Further evaluation reveals hepatomegaly and abnormal liver function tests.  Which of the following enzyme deficiencies is the most likely cause of this patient’s condition?
    • A. 

      Galactose-1-phosphate uridyl transferase

    • B. 

      Aldolase B

    • C. 

      Fructokinase

    • D. 

      Galactokinase

    • E. 

      Acid α- glucosidase

  • 23. 
    A colony of cells is exposed to high-dose cortisol in an experimental setting.  Which of the following intracellular substances is most likely to increase immediately after the exposure?
    • A. 

      CAMP

    • B. 

      IP3

    • C. 

      Unbound hsp90

    • D. 

      Activated Ras

    • E. 

      Phosphorylated JAK

    • F. 

      MRNA

  • 24. 
    Inhibition of lactate dehydrogenase in strenuously exercising skeletal muscles would eventually lead to an inhibition of Glycolysis due to intracellular depletion of which of the following substances?
    • A. 

      AMP

    • B. 

      FADH2

    • C. 

      NAD

    • D. 

      Carnitine

    • E. 

      Pyruvate

    • F. 

      Citrate

  • 25. 
    Activity of an enzyme called aldose reductase in the lens of a healthy individual produces sorbitol that can not exit the cells.  Which of the following is the most likely product of sorbitol oxidation in these cells?
    • A. 

      Glucose

    • B. 

      Fructose

    • C. 

      Galactose

    • D. 

      Galactitol

    • E. 

      Xylulose