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This section includes 199 Mcqs, each offering curated multiple-choice questions to sharpen your Biochemistry knowledge and support exam preparation. Choose a topic below to get started.
151. |
Restriction maps |
A. | allows comparison between DNA molecules without the need to determine nucleotide sequence |
B. | allows comparison between DNA molecules but requires to determine nucleotide sequence |
C. | does not allow comparison between DNA molecules |
D. | none of the above |
Answer» B. allows comparison between DNA molecules but requires to determine nucleotide sequence | |
152. |
ATP is from which general category of molecules? |
A. | Polysaccharides |
B. | Proteins |
C. | Nucleotides |
D. | Amino acids |
Answer» D. Amino acids | |
153. |
In glycolysis, ATP is formed by the transfer of a high-energy phosphate from 1,3-bisphosphoglycerate to ADR No such high-energy phosphate donor has ever been isolated in mitochondria because |
A. | the techniques for isolating the phosphate donor are not refined enough |
B. | no such phosphate donor exists |
C. | the high-energy phosphate donor is very short-lived and difficult to isolate |
D. | None of the above |
Answer» C. the high-energy phosphate donor is very short-lived and difficult to isolate | |
154. |
Which of the following is not true of glycolysis? |
A. | ADP is phosphorylated to ATP via substrate level phosphorylation |
B. | The pathway does not require oxygen |
C. | The pathway oxidizes two moles of NADH to NAD+ for each mole of glucose that enters |
D. | The pathway requires two moles of ATP to get started catabo-lizing each mole of glucose |
Answer» D. The pathway requires two moles of ATP to get started catabo-lizing each mole of glucose | |
155. |
When concentration of the reactants is higher than the equilibrium concentration then |
A. | the gibbs free energy will be positive |
B. | the gibbs free energy will be negative |
C. | more products will be formed |
D. | both (b) and (c) |
Answer» E. | |
156. |
The glycolytic pathway (glucose → 2 pyruvate) is found |
A. | in all living organisms |
B. | primarily in animals excluding particles |
C. | only in eukaryotes |
D. | only in yeast |
Answer» B. primarily in animals excluding particles | |
157. |
DNA fragments in a restriction digest can be separated by electrophoresis in |
A. | poly acrylamide |
B. | agarose gel |
C. | both (a) and (b) |
D. | none of these |
Answer» D. none of these | |
158. |
What technique can be used to determine the murderer who left blood with the victim? |
A. | DNA sequencing |
B. | PCR amplification |
C. | Western blot |
D. | RFLP mapping |
Answer» C. Western blot | |
159. |
Double stranded DNA denaturation with specified limit of temperature is |
A. | reversible reaction |
B. | irreversible reaction |
C. | either (a) or (b) |
D. | none of these |
Answer» B. irreversible reaction | |
160. |
The viruses that can achieve neoplastic transformation are called |
A. | DNA tumor viruses |
B. | RNA tumor viruses |
C. | retroviruses HIV |
D. | none of these |
Answer» B. RNA tumor viruses | |
161. |
For gene transfer to be effective, transforming DNA must be |
A. | incorporated into the bacterial chromosome |
B. | incorporated into a viral genome |
C. | free in the bacterial cytoplasm |
D. | none of the above |
Answer» B. incorporated into a viral genome | |
162. |
Which of the following regulates glycolysis steps? |
A. | Phosphofructokinase |
B. | Hexose kinase |
C. | Pyruvate kinase |
D. | All of these |
Answer» E. | |
163. |
Fructose-2,6-bisphosphate |
A. | activates fructose-1,6-bisphosphatase |
B. | activates phosphofructokinase |
C. | inhibits fructose-1,6-bisphosphatase |
D. | both (b) and (c) |
Answer» E. | |
164. |
Glycogen has |
A. | α-1,4 linkage |
B. | α-1,6 linkages |
C. | α-1,4 and α-1,6 linkages |
D. | α-1,4 and β-1,6 linkage |
Answer» D. α-1,4 and β-1,6 linkage | |
165. |
Glucose from the breakdown of glycogen is obtained in |
A. | the liver by phosphorolysis |
B. | the muscles by phosphorolysis |
C. | the muscles by hydrolysis |
D. | both (a) and (b) |
Answer» E. | |
166. |
What condition is caused by iodine deficiency during pregnancy and is characterized by stunted growth, deafness, and mental retardation? |
A. | Cretinism |
B. | Keshan disease |
C. | Multiple sclerosis |
D. | Crohn's disease |
Answer» B. Keshan disease | |
167. |
Chronic consumption of excess selenium can lead to |
A. | brittle hair and nails. |
B. | muscle weakness, |
C. | TPN |
D. | diarrhea. |
Answer» C. TPN | |
168. |
During glycolysis, the major energy generating step involves |
A. | pyruvate kinase |
B. | phosphoglycerate kinase |
C. | glyceraldehyde-3 -dehydrogenase |
D. | Phosphofructokinase |
Answer» D. Phosphofructokinase | |
169. |
The general term used for the anaerobic degradation of glucose to obtain energy is |
A. | Anabolism |
B. | Oxidation |
C. | Fermentation |
D. | Metabolism |
Answer» D. Metabolism | |
170. |
Unfolding of regular secondary protein structure causes |
A. | Large decrease in the entropy of the protein |
B. | Little increase in the entropy of protein |
C. | No change in the entropy of the protein |
D. | Large increase in the entropy of the protein |
Answer» E. | |
171. |
The study of energy relationships and conversions in biological systems is called as |
A. | Biophysics |
B. | Biotechnology |
C. | Bioenergetics |
D. | Microbiology |
Answer» D. Microbiology | |
172. |
The PCR, polymerase chain reaction is becoming the method of choice for |
A. | Alteration of gene |
B. | screening gene |
C. | sterilization of gene |
D. | all of these |
Answer» C. sterilization of gene | |
173. |
Site directed mutagenesis facilitated research on |
A. | Carbohydrates |
B. | Proteins |
C. | Lipids |
D. | Fats |
Answer» C. Lipids | |
174. |
Dextrin hydrolysis yields |
A. | D-galactose and D-glucose |
B. | 2-Dglucose |
C. | n-Dglucose |
D. | 2-Dfructose |
Answer» D. 2-Dfructose | |
175. |
Glycolysis converts |
A. | Glucose into pyruvate |
B. | Glucose into phosphoenolpyruvate |
C. | Fructose into pyruvate |
D. | Fructose into phosphoenolpyruvate |
Answer» B. Glucose into phosphoenolpyruvate | |
176. |
The product formed in the first substrate level phosphorylation in glycolysis is |
A. | Pyruvate |
B. | 3-phosphoglycerate |
C. | 1, 3-bisphosphoglycerate |
D. | 2-phosphoglycerate |
Answer» C. 1, 3-bisphosphoglycerate | |
177. |
An endemic disease of cardiomyopathy in children is attributed to |
A. | low Se in the environment |
B. | low intake of iron |
C. | high Se in the environment |
D. | high intake of iron |
Answer» B. low intake of iron | |
178. |
Manganese is a key component of all of the following enzymes except |
A. | arginase |
B. | pyruvate carboxylase |
C. | ceruloplasmin |
D. | Mn-superoxide dismutase |
Answer» D. Mn-superoxide dismutase | |
179. |
In a PCR reaction after four cycles, each molecule of a duplex DNA will give rise to |
A. | 16 single strands of DNA |
B. | 16 double stranded DNA |
C. | 18 single strands of DNA |
D. | 18 double stranded DNA |
Answer» B. 16 double stranded DNA | |
180. |
Consumption of which nutrient leads to the multiplication of oral bacteria? |
A. | Fat |
B. | Carbohydrate |
C. | Protein |
D. | Fluoride |
Answer» C. Protein | |
181. |
The mineral which is considered important in maintaining electrical potential in nerves and membranes is |
A. | magnesium |
B. | manganese |
C. | calcium |
D. | iron |
Answer» B. manganese | |
182. |
TPP (thiamine pyrophosphate) is derived from |
A. | Vitamin A |
B. | Vitamin B1 |
C. | Vitamin C |
D. | Vitamin B2 |
Answer» C. Vitamin C | |
183. |
In the reduction of pyruvate to lactate, which of the following is regenerated? |
A. | H⁺ |
B. | NADH |
C. | NAD⁺ |
D. | Na⁺ |
Answer» D. Na⁺ | |
184. |
For its activity, pyruvate decarboxylase requires |
A. | Mg⁺² |
B. | Ca⁺² |
C. | Na⁺ |
D. | H⁺ |
Answer» B. Ca⁺² | |
185. |
For every one molecule of sugar glucose which is oxidized __________ molecule of pyruvic acid are produced. |
A. | 1 |
B. | 2 |
C. | 3 |
D. | 4 |
Answer» C. 3 | |
186. |
The enzymes of glycolysis in a eukaryotic cell are located in the |
A. | intermembrane space |
B. | plasma membrane |
C. | cytosol |
D. | mitochondrial matrix |
Answer» D. mitochondrial matrix | |
187. |
The amount of energy received from one ATP is |
A. | 76 kcal |
B. | 7.3 kcal |
C. | 760 kcal |
D. | 1000 kcal |
Answer» C. 760 kcal | |
188. |
The active form of glycogen phosphorylase is phosphorylated, while the dephosphorylation of which active form occurs? |
A. | Glycogen synthase |
B. | Glycogen semisynthase |
C. | Glycogen hydrolase |
D. | Glycogen dehydrogenase |
Answer» B. Glycogen semisynthase | |
189. |
In the glycogen synthase reaction, the precursor to glycogen is |
A. | glucose-6-P |
B. | UTP-glucose |
C. | UDP-glucose |
D. | glucose-1-P |
Answer» D. glucose-1-P | |
190. |
Phosphofructokinase, the major flux-controlling enzyme of glycolysis is allosterically inhibited and activated respectively by |
A. | ATP and PEP |
B. | AMP and Pi |
C. | ATP and ADP |
D. | Citrate and ATP |
Answer» D. Citrate and ATP | |
191. |
From a single molecule of DNA, PCR can make |
A. | one additional copy |
B. | hundreds of copies |
C. | thousands of copies |
D. | millions of copies |
Answer» E. | |
192. |
Which of the following is not a mechanism for altering the flux of metabolites through the rate-determining step of a pathway? |
A. | Allosteric control of the enzyme activity |
B. | Diffusional coupling between adjacent active sites |
C. | Genetic control of the enzyme concentration |
D. | Covalent modification of the enzyme |
Answer» C. Genetic control of the enzyme concentration | |
193. |
Genomic libraries are made from |
A. | genomic DNA of an organism |
B. | genomic RNA of an organism |
C. | genomic cDNA of an organism |
D. | genomic mRNA of an organism |
Answer» B. genomic RNA of an organism | |
194. |
Which of the following could act as an uncoupler of electron transport and ATP synthesis? |
A. | The Fo base-piece of ATP synthase (without the Fl subunit) |
B. | Dinitrophenol |
C. | neither (a) nor (b) |
D. | Both (a) and (b) |
Answer» E. | |
195. |
To clone into a plasmid vector, both the plasmid and the foreign DNA are cut |
A. | with the same restriction enzyme and mixed together |
B. | with different restriction enzyme and mixed together |
C. | with the combination of enzymes and then seperated |
D. | with the combination of enzymes and mixed together |
Answer» B. with different restriction enzyme and mixed together | |
196. |
PCR is used |
A. | to diagnose genetic diseases |
B. | to solve crimes |
C. | to study gene function |
D. | all of these |
Answer» E. | |
197. |
Bacteriophages are |
A. | cells in the blood that eat bacteria |
B. | a class of bacteria |
C. | bacterial viruses |
D. | none of the above |
Answer» D. none of the above | |
198. |
Specialized transduction occurs when |
A. | the bacteriophage incorporates randomly in the bacterial chromosome |
B. | the bacteriophage never incorporates into the bacterial chromosome |
C. | the bacteriophage always incorporates at the same position in the bacterial chromosome |
D. | none of the above |
Answer» D. none of the above | |
199. |
PCR can be used to amplify a specific fragment of DNA from which of the following? |
A. | A drop of blood |
B. | A hair follicle |
C. | A fragment of skin |
D. | All of these |
Answer» E. | |