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تحميل الدليل التدريبي

أسئلة شائعة


بسم الله الرحمن الرحيم

BCH 475

نموذج إمتحان نهائي لمادة الكيمياء الحيوية للمسرطنات


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

1- In development of colon cancer, the benign formed after the polyp formation.             

2- Direct-acting carcinogens chemically modify certain nucleotides by reacting

     with nitrogen and oxygen atoms in DNA.                                                                 

3- Quinolines found in an industrial products and they found in tobacco smoke.   

4- The malignant tumor site contains invasive tumor cells and normalepithelial


5- The aromatic or heterocyclic amines metabolism can lead to ring epoxy

     derivatives by reducing the hydrodiols ar rearrange the diphenols.                

6- The hyperactive mutant protein produces from altered coding sequence on the


7- In animals, activation of indirect-acting carcinogens like insecticides often is 

     carried out by lung enzymes.                                                                                   

8-  Aromatic amines are analogs of aniline and they activated to nitrenium (N+) ion.

9-  The class II adenoma is the last stage before malignancy development.                    

10-The epigenetic carcinogens have direct interaction with genetic materials.       

11- Benzo(a)pyrene activated by epoxide hydralase in human cells.                    

12- Because they easily detoxified, the polycyclic arylamines are not

       carcinogenic compounds.                                                                                        

13- Major classes of cancers derived from epithelial cells because they are surface

       cells and they suffer exposure to dangerous chemicals and harmfull radiation  

14- The heterocyclic amines consist from single or multiple ring systems with

       exocyclic amino group.                                                                                         

15- Many carcinogens are or can be biotransformed to electrophiles that react

       covalently with DNA.                                                                                           

16- Cocarcinogens are agents which have strong carcinogenicity effect.            

17- Tumor known when regulated cells have descendants that inherit the

       propensity to proliferate without responding regulation.                                          

18- The undifferentiated cancer is the last step in neoplastic development.           

19- Azo compounds are synthetic chemicals found in nature including 4


20- The halo ethers are halogens and they do not activated by electron transfer.              

21- Benign tumor referring to a tumor containing cells that closely similar to the

       normal cells.                                                                                                         

22- Cis-Platinum is complex chelating divalent platinum with chloride anion and

       three amino groups.                                                                                              

23- Anesthetic gases like halothane, nitrous oxide and metofane have embryotoxic


24- Indirect-acting carcinogens acts as potent cancer inducers only after conversion

       to ultimate carcinogens.                                                                                         

25-Under an aqueous condition, Nitrosamides can be hydrolytic decomposition.           



Q2; Each question has four multiple choices. Please mark the correct and the incorrect one:

1- The lumen of colon in malignant tumor development contains of:

A-        Blood vessel.                                                                                       

B-        Invasive tumor cells.                                                                             

C-        The polyp.                                                                                           

D-        Basal lamina.                                                                                       

2- STEVIA is:

A-        Preservatives.                                                                                      

B-        Stevioside.                                                                                           

C-        Powdered dietary.                                                                               

D-        Flavoring.                                                                                            

3-         N-acetyltransferase system found in;

            A-        Arylamines                                                                                          

            B-        Heterocyclic amines                                                                             

            C-        Quinolines                                                                                           

            D-        Azarenes                                                                                               

4- Cancer ;

A-        Caused by a mutation in somatic cells.                                      

B-        Caused by an accumulation of 3 to 20 mutations.                                  

C-        Caused by a mutation in both somatic and germ cells.               

D-        Caused by a single mutation.                                                                

5- The enzymes shown below are activated or deactivated many chemical

     Carcinogens in cellular compartments:

A-        Epoxide hydrolase.                                                       .                       

            B-        P.450.                                                                                                 

            C-        Glucuronation enzyme.                                                             

            D-        Sulfotransferase.                                                                                  

6- Many of indirect-acting carcinogens are;

A-        fat-soluble compounds                                                               

B-        accumulate in fat cells and lipid membranes.                                          

C-        Excreted from the body as they are                                                      

D-        Converted to water-soluble derivatives                                     

7- In malignancy:

A-        Refer to tumor cells that invade surrounding normal tissue.                     

            B-        The malignant cells express special proteins.                                         

            C-        Cells divided more rapid.                                                                     

            D-        The cells start to died fast.                                                                    


8- The DNA adducts effect by;

            A-        Activation dependent compounds                                                         

            B-        Promoter compounds                                                                          

            C-        Inorganic compounds                                                                           

            D-        Cytotoxic compounds                                                                          

9- The aromatic structure carcinogens;

            A-        Nitrogen mustard                                                                                 

            B-        Methyl nitrosourea                                                                               

            C-        Dimethyl sulfate                                                                                   

            D-        Safrol                                                                                                    

10- The metastasis:

            A-        Known as spread of tumor cells and establishment of secondary

area of growth.                                                                        

            B-        All malignant cells have an ability to metastasized.                                  

            C-        Charachterized from benign ones by invasiveness and spread.   

            D-        Is the last step in tumor development.                                         

11- The Acesulfame-K:

A-        Is artificial color.                                                                                  

B-        Found in chewing gum.                                                            

C-        Found in gelatine.                                                                                 

D-        Occur in nature.                                                                                   

12- The carcinogens promotion stage includes:

A-        Activated carcinogens binds to DNA.                                      

            B-        Alteration in DNA structure.                                                                

            C-        Stimulation of DNA replication                                                 

            D-        Transformed cell formation.                                                                  

13-       Most of mutagenic chemicals found in the Salmonella Typhimurium TA98 are;

PAHs   compounds                                                                                          

Azo compounds                                                                                              

Imidazoquinoline compounds                                                                           

Quinoxaline compounds                                                                                   

14-       Malignant tumors classes:

            A-        Sarcomas derived from endoderm.                                                       

            B-        Carcinomas derived from endoderm and mesoderm.                             

            C-        All malignant tumors are solid masses.                                       

            D-        Leukemias is a class of ectoderm.                                                        

15-       Nitrosamines:

A-        Form reactive carbonium (C+) ions.                                                       

            B-        Contaminates of cereal grains and peanuts.                                           

            C-        Analogs of aniline.                                                                                

            D-        Formed by reaction of nitrite with amines at low pH.                 

16-       The epigenetic carcinogens is;

A-        Inorganic                                                                                             

B-        Cytotoxic                                                                                            

C-        Activation dependent                                                                           

D-        Peroxisome proliferators                                                                      

17- Yellow 6 is artificial coloring found in:

A-        Cherries in fruit cocktail.                                                                      

            B-        Baked goods.                                                                                                  C-        Pet food.                                                                                             

            D-        Gelatin.                                                                                    

18- Genes and cancer:

            A-        Proto-oncogenes are mutant genes that promotes cancer.                     

            B-        Tumor-suppressor genes work as anti-proto-oncogene.                       

            C-        Proto-oncogenes produce from mutated an oncogene.                

            D-        Both oncogenes and proto-oncogenes prevent unwanted cell


19- Carcinogene Stages:

            A-        In the initiation stage leads to deactivation and excretion.                       

            B-        In the initiation stage covalent binding to DNA leads to error and

free repair.                                                                                           

            C-        In promotion stage start with derepression of chromosomal


            D-        In promotion stage transformed cells leads to immune surveillance.  

20- PAH:

A-        Formed by combustion of carbonaceous materials.                               

            B-        Activated by epoxidation.                                                                    

            C-        Have promoter activity.                                                            

            D-        Cause skin and lung cancer.                                                                 

21-Saccharin is;

A-        Activation independent carcinogens.                                                     

B-        Inorganic carcinogens.                                                             

C-        Hormone modifying carcinogens.                                                          

D-        Activation dependent carcinogens.                                                       

22- The plastics is;

A-        DNA reactive carcinogens.                                                                  

B-        Epigenetic carcinogens.                                                            

C-        Solid state carcinogens.                                                            

D-        Inorganic.                                                                                            

23- Nitroso compounds ;

A-        Derived from primary amines or amides.                                               

B-        Have carcinogenic effects.                                                                    

C-        Cause alkylation of DNA in liver cells.                                      

D-        Do not found in antibiotic drugs.                                                           



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