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تحميل الدليل التدريبي

أسئلة شائعة


بسم الله الرحمن الرحيم

451 BCH

نموذج من الإمتحان النهائي لمادة حيود الأيض



Please mark the correct statements with (T) and the incorrect one with (X):


1- Hypoammonemia caused by the defect of all urea cycle enzymes.                 

2-The diploid organism contains two copies of every gene, excepting

     those carried on the sex chromosomes.                                                                     

3- G6PD deficiency is a sex-linked affecting males and being carried by


4- In diabetic ketosis, liver produces large amounts of ketone bodies,

     which lead to decrease in pH then impairs tissue function such as

     central nervous system.                                                                                          

5- For an autosomal recessive trait to be expressed, both copies of a gene

     pair must be present in a mutant form.                                                                    

6- Homogentisate is abnormal intermediate in the degradation of

     phenylalanine and tyrosine amino acids.                                                                  

7- A person who is homozygous for aa has inherited the a allele from his

     great-grandmother then transmitted through one parent.                                          

8- When 2,4-Dinitrophenylhydrazone react with α-KA the result will be

    2,4-dinitrophenylhydrozone derivative.                                                                    

9- The component activity in replication that reduces the number of

     mis- incorporated bases known as postreplication repair system.                            

10-Phenylketonuria symptoms including the decrease in brain weight,

     myelination of their nerves is defective and their reflexes are


11-When the transferase is not active in the lens of the eye then the

      presence of aldose Reductase causes the accumulating galactose to

      be reduced to galactitol.                                                                                       

12-Porphyrin biosynthesis is taking place in liver and phagocytes and

      either site might be the disorder site.                                                                      

13-The homologue is referred to each chromosome is derived from a

      different parent which is known as homozygous.                                                    

14-Tyrosinemia symptoms are absence of pigmentation, scoliosis and


15-Type 2 DM is a homogeneous syndrome resulting from defects of

     both insulin secretion and action.                                                                            

16-hypolipidemia phenotypes result from defects in either lipoprotein

    synthesis, metabolism, or uptake by tissues.                                                  

17-The possible cause of hyperammonemia is that elevated levels of

     glutamate formed from NH4+ and glutamine.                                                         

18-Recessive mutation is known in which both alleles must be mutant.               

19-Carnitine deficiency can affect the cardiac muscle and result in poor 

      cardiac contraction known as cardiomyopathy.                                                     

20- The congenital erythropoietic porphyria causes prematurely erythrocytes

      hemolysis which caused by insufficient cosynthase.                                        

21-A severe mutation might occur during recombination events when

      some pieces of DNA can move to different positions in the genome.                     

22-In MODY2, the hyperglycemia linked with GCK mutation is often mild.      

23-The cystathionine-β-synthase deficiency caused homocystinuria which

      occurs in methionine catabolic pathway.                                                                

24-Phenylketonuria can be detected in newborns by screening urine samples

     with 2,4-Dinitrophenylhydrazone.                                                                          

25-In diabetic ketosis, liver produces large amounts of ketone bodies, which

      leads to decrease in pH then impairs tissue function such as central nervous 


26-In Coris disease, lysosomes become engorged with glycogen because they

     lack alpha-1,4-glucosidase.                                                                         

27-In spontaneous depurination, both purines and pyrimidines are stable under

     normal cellular condition.                                                                                       

28- In methylmalonic acidemia, some patients might respond to the therapy

     of vitamin B6 to activate the deficient enzyme which called methylmalonyl-

     CoA mutase.                                                                                                         

29- Hyperammonemia is treated by supplementing a protein-restricted diet

      with large amount of benzoate and phenylacetate.                                       

30- Type 2 DM is a homogeneous syndrome resulting from defects of both

insulin secretion and action.                                                                             

Q2; Choose the ONLY one correct answer for each question.

1-         One of the carnitine function in F.A. metabolism is;

            A-        To shuttle long-chain F.A. out of mitochondria                          

            B-        To shuttle short-chain F.A. out of mitochondria                        

            C-        To shuttle long-chain F.A. into mitochondria                                       

            D-        To shuttle short-chain F.A. into mitochondria                            


2-         The muscle phosphorylase activity is absent in;

            A-        McArdle glycogen-storage disease (type V)                                       

            B-        Von Gierke glycogen-storage disease (type I)                          

            C-        Cori glycogen-storage disease (type III)                                             

            D-        Andersen glycogen-storage disease (type IV)                           


3-         The non-sex-linked genes are referred to:

            A-        Dominants       

            B-        Autosomal       

            C-        Recessive        

            D-        Sex-linked         


4-         Sever hemolytic anemia caused by;

            A-        glycogen-storage disease                                                                       

            B-        Carnitine deficiency                                                                           

            C-        G6PD deficiency                                                                                

            D-        All the above statements are incorrect                                        


5-         In germ cell mutation;

            A-        Causes somatic cell mutation

            B-        Occurs during mitosis     

            C-        Occurs only in haploid cells.     

            D-        Is known as dominant mutation.           


6-         There are other metabolic pathways that can generate NADPH in all cells EXCEPT;

            A-        Hepatocytes                                                                                      

            B-        Muscle Cells                                                                                      

            C-        Adipocytes                                                                                        

            D-       RBC                                                                                                   


7-         The heterozygous parents have;

A-                Each parent has one mutant and one wild-type allele.    

B-                Mutation in both allele              

C-                Autosomal recessive trait                     

D-                Abnormal phenotype                                      


8-         In Parkinson's disease;

            A-        Monoamine is precursor of the dopamine                                           

            B-        Monoamine oxidase is responsible for oxidative deamination of


C-        Monoamine oxidase is responsible for oxidative deamination and degradation of Dopamine                                                                   

D-        Dopamine oxidase is responsible for oxidative deamination of


9-         In recessive transmission of enzyme deficiencies;

            A-        The enzyme is insufficient in heterozygote.         

            B-        The enzyme is insufficient in homozygote mutant.           

            C-        The enzyme is insufficient in both heterozygote and homozygote.         

            D-        The enzyme and its substrate are insufficient in both heterozygote

                        and homozygote.         

10-       Patients who have Von Gierke disease have an increased dependence on;

            A-        protein metabolism                                                                             

            B-        Fat metabolism                                                                        

            C-        Glycogen metabolism                                                                        

            D-        All the above are incorrect                                                                 

11-       In "One gene, one enzyme" concept.

            A-        In mutant gene, the end product will be accumulated.    

            B-        Mutation of a gene leads to deficiency of the substrate.   

            C-        Mutation of a gene leads to deficiency of the enzyme and the substrate

            D-        All the above is incorrect                                                          


12-       One of the primary affected organs in carnitine deficiency is;

            A-        Liver                                                                                       

            B-        Adipose tissue                                                                         

            C-        Brain                                                                                       

            D-        Kidney                                                                                                  


13-       The X-chromosome is important because;

            A-        It carries genes that are critical for all inherited diseases in human         

            B-        It carries genes affected males than females                                         

            C-        It carries genes that are critical for human survival                               

            D-        Any gene located on this chromosome called X-linked gene                


14-       GCK enzyme

A-                converts glucose to glucose 6- phosphate in pancreatic Beta cells

and hepatocytes                                                                

B-                converts glucose to glucose 6- phosphate in pancreatic Beta cells

and adipocytes                                                                                   

            C-        It’s defect causes an increase in glycogen accumulation               

            D-        It’s defect related to IDDM                                                                


15-       The recessive mutation;

            A-        May leads to gain function        

            B-        May increase the activity of gene product         

            C-        Individual must be a heterozygous          

            D-        Individual must be a homozygous                    


16-       In albinism:

            A-        The DOPA Quinone is accumulated                 

            B-        Both DOPA and DOPA Quinone are deficient  

            C-        Homogentisic acid oxidase will be deficient  

            E-        Phenylalanine will be accumulated                      


17-       The polygenic disorder is

            A-        Hypolactasia                                                                                      

            B-        Galactosemia                                                                                     

            C-        T2DM                                                                                               

            D-        Carnitine deficiency                                                                            


18-       In dominant and recessive mutation;

            A-        A capital is wild allele in dominant mutation                   

            B-        B capital is recessive mutant allele                                 

            C-        In segregation of dominant mutation, A/a is  mutant  

            D-        In segregation of recessive mutation, b/B is  mutant  

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