2017 biochem endterm Flashcards
Which condition decreases the solubility of uric acid?
a. High Na+
b. High Ca+
c. High glucose
d. High H+
d. High H+
What is the allosteric activator for glycogen to glucose 1 phosphate?
a. AMP
b. ATP
c. Glucose 6 phosphate
a. AMP
What is the function of calcitriol?
a. Increases the absorption of Ca and phosphate from GI
b. Stimulate bone reabsorption
c. Stimulate excretion of Ca and K by the kidney
a. Increases the absorption of Ca and phosphate from GI
Biotin is a co-factor in which biochemical reaction?
a. Carboxylation
b. Esterification
c. Deamination
d. Hydration
a. Carboxylation
Which enzyme catalyzes oxidative deamination reaction?
a. Glutamate decarboxylase
b. Glutamate dehydrogenase
c. Glutamate lyase
d. Glutamate synthase
b. Glutamate dehydrogenase
What is associated to the assembly of chylomicron in the intestine?
a. Sterol binding protein
b. Microsomal triacylglycerol transfer protein
c. Cholesterol ester transfer protein
d. Insulin-induced binding protein
b. Microsomal triacylglycerol transfer protein
What is the role of gastric HCl in digestion?
a. Activates trypsin
b. Denatures proteins
c. Hydrolyses lipids
d. Releases free amino acids
b. Denatures proteins
Which of the following is an amino acid in the urea cycle?
a. Alanine
b. Ornithine
c. Trypsin
b. Ornithine
In type 1a glycogen storage disease, if the liver lacks glucose-6-phosphatase what will result as a consequence?
a. Hypoglycemia
b. Hyperglycemia
c. Lack in Na+
a. Hypoglycemia
Which carbohydrate does not contribute to the energy supply in humans?
a. Starch
b. Sucrose
c. Cellulose
d. Glycogen
c. Cellulose
What is the main source of ketone bodies?
a. Beta oxidation of fatty acids
b. Glucose
c. Pentose pathway
d. Proteins
a. Beta oxidation of fatty acids
The deficiency of what enzyme leads to farber disease?
ceramidase
The moderate deficiency of which mineral, when accompanied by increased sodium intake, increases the risk of hypertension?
a. Ca
b. K
c. Iron
d. Zinc
b. K
The protocol requires the addition of cholesterol-esterase for the laboratory investigation of blood plasma cholesterol levels using cholesterol oxidase, what would you measure if cholesterol-esterase was omitted?
a. Free cholesterol
b. HDL cholesterol
c. LDL cholesterol
d. Total cholesterol
a. Free cholesterol
Which activated is used for purine and pyrimidine synthesis?
a. Ribose – 5 phosphate
b. 5-Phosphoribosyl -1- pyrophosphate PRPP
b. 5-Phosphoribosyl -1- pyrophosphate PRPP
Which sweetener has been suggested to be of the greatest benefit for diabetic patients?
a. Acesulfame-k
b. Aspartame
c. Stevia glucoside
d. Sucrose
c. Stevia glucoside
In obese people, what leads to glucose intolerance?
a. Cytokine – mediated sub-inflammatory stage
b. Release of leptin from adipose tissue
c. Glucose – induced incretin release from the GIT
a. Cytokine – mediated sub-inflammatory stage
What mediates the synthesis of inositol triphosphate from glycerophospholipids?
a. Phospholipase A1
b. Phospholipase A2
c. Phospholipase C
d. Phospholipase D
c. Phospholipase C
Male patient O2 consumption: 0.2 L CO2 consumption: 0.71 L Based on this, what can we predict about his diet? a. Carbohydrate based b. Protein based c. Fat based d. Mixed diet
d. Mixed diet
Which of the following initiates protein digestion in the stomach?
a. Trypsin
b. Pepsin
c. Elastase
d. Chymotrypsin
b. Pepsin
What best describes the digestion and absorption of dietary lipids?
a. Lipid digestion starts in the mouth and halts in the stomach
b. Triglycerides are absorbed directly in the stomach
c. Lipid digestion is complete in the large intestine
d. Fatty acids are absorbed by intestinal mucosal cells
d. Fatty acids are absorbed by intestinal mucosal cells
What is the condition associated with the high consumption of trans fat in food?
a. High blood ammonia
b. High ketone body production
c. Hypercholesterolemia
d. Hypoglycemia
c. Hypercholesterolemia
Why does the liver contain glycokinase instead of hexakinase?
a. Allows glucose uptake to low concentration
b. Prevent the liver producing too much glucose
c. Satisfy the high energy demand of liver
d. Allow rapid intake of glucose after meal
d. Allow rapid intake of glucose after meal
Why is linoleic acid (C18:2) an essential fatty acid?
a. Lack of 12 desaturase activity
b. Lack of 9 desaturase activity
c. High 18:4 desaturase activity
a. Lack of 12 desaturase activity
What is the key characteristic of all membrane lipids?
a. Amphipathic
b. Unsaturated
c. Hydrophilic
a. Amphipathic
What is the product of de novo purine biosynthesis?
a. IMP
b. UMP
a. IMP
What regulates carnitine shuttle?
malonyl CoA
Which pair of vitamin-disease is correctly matched?
a. Vitamin C, scurvy
b. Vitamin D, night blindness
c. Vitamin E, beriberi
a. Vitamin C, scurvy
What makes the membrane fluid?
a. Cis unsaturated fat
b. Trans unsaturated fat
c. PUFA
d. Saturated fats
a. Cis unsaturated fat
What causes celiac disease?
a. Gluten
b. Glucose
c. Cellulose
a. Gluten
What is the first step in protein sequencing?
a. N-termis label
b. C-termis label
c. First peptide bond label
d. Polypeptide hydrolysis
a. N-termis label
Which of the following is a regulatory transcription factor?
a. GTF
b. CREB
c. TGF-beta
d. JAK
b. CREB
What happens when there is a lack of vitamin C?
a. No hydrolysis of lysine in collagen
b. No hydroxylation of proline in collagen
c. No crosslink of proline in collagen
d. No crosslink of lysine in collagen
b. No hydroxylation of proline in collagen
