Biochemistry MCQs are very important to pass the initial tests of Army Medical Tests, AFNS, Admission in Medical Colleges and Nursing Jobs. In medical fields, MCQs in Biochemistry have been repeated in the academic tests of Short Services Regular Commission of Army, Navy and PAF.

Candidates who have their degrees particularly in the fields of Biochemistry, they can join Pak Army as a direct Captain or Major through Short Service Commission. 

In Pak Navy, Biochemistry MCQs help to pass the initial tests of M-Cadet. Moreover, Biochemistry MCQs are the past experience of the candidates who have given academic tests of Medical Officers in Pakistan Air Force and they are working as a Doctor with different specialized field.

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Biochemistry MCQs Questions With Answers PDF

Following Biochemistry MCQs are very helpful for the admission tests of medical entrance tests. 

Which of the following combination is correct ?

A. Thiamine – Acyl CoA
B. Biotin-CO₂
C. ATP-Hydrogen
D. All of the above

Insulin increase the following pathways in liver EXCEPT_______?

A. Fatty acid synthesis
B. Glycogen synthesis
C. Protein syntehsis
D. Glucose synthesis

Most lipogenic_____?

A. Fructose
B. Glucose
C. Galactose
D. Ribose

Type II glycogen storage disorder is due to deficiency of______?

A. Alpha -Glucosidase
B. Alpha galactosidase
C. Muscle phosphorylase
D. Acid Lipase

Dietary fiber is rich in_______?

A. Starch
B. Cellulose
C. Collagen
D. Inulin

Fructose intolerance is to______?

A. Fructose only
B. Fructose and glucose
C. Sucrose only
D. Fructose and sucrose

The monsaccharide glucose is best described by which one of the following statements ?

A. It usually exists in the furanose form
B. It is a ketose
C. It possesses an anomeric C-2 carbon atom
D. It forms part of the disaccharide sucrose

Number of ATP molecules generated in the conversion of glycogen of lactate is_______?

A. 2
B. 36
C. 38
D. 32

NADPH is generated by the action of______?

A. Glucose 6 phosphate dehydrogenase
B. Glucose 1 phosphate dehydrogenase
C. Glucose 1,6 diphosphate dehydrogenase
D. All of the above

HMP shunt is of great importance in cellular metabolism because its produces______?

A. ATP
B. ADP
C. Acetyl CoA
D. NADPH

Glucose 6 phosphatase deficiency is seen in______?

A. Pomper’s disease
B. Von Gierke’s disease
C. McArdles syndrome
D. Downs syndrome

Sites where HMP shunts can occur include_____?

A. Liver
B. WBC
C. Lactating mammary gland
D. Testes
E. All of the above

Step in HMP pathway requiring TPP______?

A. G6 PD
B. 6 phosphogluconate dehydrogenase
C. Transketolase
D. Transaldolase

1 molelcule of glucose forms _______ molecules of pyruvate?

A. 1
B. 2
C. 3
D. 4

The main pathways of metabolism in brain are______?

A. Glycolysis and citric acid cycle
B. Glycogenolysis and Gluconeogenesis
C. Embden-Meyerhof Pathway and H.M.P shunt
D. Glycogenolysis and Citric and cycle

In glycolysis ATP is produced by the following enzyme______?

A. Hexokinase
B. Phosphoglycerate kinase
C. Enolase
D. Phosphohexose isomerase

Inhibition of glycolysis by O2 is known a_______?

A. Muni effect
B. Pasteur effect
C. Hill reaction
D. Gluconeogenesis

Which one of the following is the correct sequential order in which the given enzymes of kreb’s cycle are formed after a molecule of acetyl CoA_______?

A. Citrate, Oxalocetate, Ketoglutarate
B. Ketoglutarate, Oxalocetate, Citrate
C. Citrate, Ketoglutarate, Oxalocetate
D. Oxalocetate, Ketoglutarate, Citrate

Kreb’s cycle does not occur in_____?

A. Muscle
B. RBC
C. Heart
D. All of the above

In TCA cycle or tricarboxylic acid cycle, which is first formed_______?

A. Isocitrate
B. Citrate
C. Succinate
D. Fumarate

Renal threshold for glucose is________?

A. 80 mg%
B. 100 mg%
C. 180 mg/ dl
D. 200 mg%

The key enzyme of gluconeogenesis is_______?

A. Pyruvate carboxylase
B. Fructose 1,6 disphosphatase
C. Glucose 6 phosphatase
D. Phosphoenol pyruvate carboxykinase

Which one of the following is a monosaccharide____?

A. Maltose
B. Sucrose
C. Fructose
D. Strach

Which of the following is abnormal constituent of urine______?

A. glucose
B. Creatine
C. Urea
D. None of the above

The conversion of glucose 6-P to fructose 6-P is an example of which of the following reactions______?

A. Phosphate transfer
B. Isomerisation
C. Dehydration
D. Aldol cleavage

Cane sugar is______?

A. Glucose
B. Surose
C. Fructose
D. Maltose

In TCA, substrate level phospherylation takes place in_______?

A. Alpha ketoglutrate to succinyl CoA
B. Succinyl CoA to Succinate
C. Succinate to fumarate
D. Oxalocetate to citrate

Enzymes concerned with the citric acid cycle are found in the_____?

A. Nucleus
B. Ribosomes
C. Mitochondria
D. Nonparticulate cytoplasm

All of the following are substrates for gluconeogenesis except_______?

A. Alanine
B. Oleic acid
C. Glycerol
D. Tryptophan

During conversion of glycerol to pyruvic acid, the first glycolytic intermediate to form is_____?

A. 2- phospho glyceric acid
B. 3- phospho glyceric acid
C. 3- phospho glyceralehyde
D. Dihydroxy acetone phosphate

The first product of glycogenolysis is______?

A. Glucose 6 phosphatase
B. Glucose 1,6 diphosphatase
C. Glucose 1- phosphatase
D. Fructose 1- phosphatase

Glucose can be synthesized from all except_______?

A. Amino acids
B. Glycerol
C. Acetoacetate
D. Lactic acid

The tissue with the highest glycogen content (mg/100gm)____ ____?

A. Liver
B. Muscle
C. Kidneys
D. Testes

Major contribution towards gluconeogenesis is by________?

A. Lactate
B. Glycerol
C. Ketones
D. Alanine

An essential for the conversion of glucose to glycogen in liver is______?

A. UTP
B. GTP
C. Pyruvate Kinase
D. Guanosine

Which of the following enzymes use NADP as coenzyme _________?

A. Glyceraldehyde 3 phosphate dehydrogenase
B. Lactate dehydrogenase
C. Glucose 6-Phosphate dehydrogenase
D. Beta hydroxy acyl CoA dehydrogenase

In prolonged starvation the main energy source of brain is______?

A. Glucose
B. Ketone bodies
C. Fructose
D. Fatty acids

The citric acid cycle is the final pathway for oxidation of________?

A. Enzymes
B. Vitamins
C. Minerals
D. None of the above

The uptake of glucose by the liver increase following a carbohydrate meal because______?

A. There is increase in phosphorylation of glucose by glucokinase
B. GLUT-2 stimulated by insulin
C. Glucokinase has a low Km for glucose
D. Hexokinase in liver has a high affinity for glucose

Which one of the following enzymes provides a link between glycolysis and the citric acid cycle ?

A. Lactate dehydrogenase
B. Pyruvate kinase
C. Citrate synthase
D. Pyruvate dehydrogenase

Increase in pyruvate and lactate is seen in which of the following deficiency ?

A. Thiamine
B. Pyridoxine
C. Niacin
D. Vitamin C

Glycogen breakdown leads to formation of_______?

A. Glucose
B. Lactic acid
C. Glucose & Lactic acid
D. Glycoprotein

Which is not a oligosaccharide sugar ?

A. Galactose
B. Lactose
C. Maltose
D. Sucrose

One molecule of acetyl Co-A gives rise to ________ ATP molecules?

A. 2
B. 8
C. 12
D. 32

All these reactions take place inside the mitochondria except_____?

A. EMP pathway
B. Krebs cylce
C. Urea cycle
D. Electron transfer

Which of the following is not a product of HMP shunt______?

A. NADPH
B. D fructose 6 phosphate
C. D sedoheptulose 5 phosphate
D. D glyceraldehyde 3 phosphate

All are true regarding glucose 6 phosphate deficiency except_______?

A. Hyperuricemia
B. Hyperglycemia
C. Defective cori cycle
D. Increased mobilization of glycogen from liver

Blood glucose level cannot be augmented by mobilization of muscle glycogen due to lack of______?

A. G-6-P dehydrogenase
B. G-6-P phydrogenase
C. Aldolase
D. Glucokinase

Galactosemia commonly is due to deficiency of______?

A. Galactose 1 phosphatase uridyl transferase
B. Galactose 1 phosphatase
C. Glucose 1 phosphatase
D. Glucose 6 phosphatase

In which type of glycogen storage disease is hyper uricemia a feature ?

A. I
B. II
C. III
D. IV

McArdles disease is due to the deficiency of_______?

A. Glucose 1 phosphatase
B. Glucose 1,6 phosphatase
C. Glucose 6 phosphatase
D. Myophosphorylase

An enzyme not involved in glycolysis is______?

A. Enolase
B. Phosphoglycero mutase
C. Aldolase
D. Glycerophosphate dehydrogenase

Phosphofructokinase is the key enzyme of______?

A. Glycolysis
B. Gluconeogenesis
C. Beta oxidation
D. TCA cycle

Which metabolite of TCA cycle is used in detoxification of ammonia in brain____?

A. Alpha ketoglutarate
B. Ornithine
C. Oxalocetate
D. Glycine

In TCA cycle, citrate is converted in to after losing a molecule of H₂O_____?

A. Isocitrate
B. Cisaconitate
C. Oxalocetate
D. Glutarate

In TCA cycle substrate level phosphorylation occurs at______?

A. Succinate dehydrogenase
B. Malonate reduction
C. Thiokinase
D. None of the above

Which of the following is correctly matched ?

A. Isocitrate to oxalo succinate -1 ATP is formed
B. Succinyl CoA to succinate -1 ATP is formed
C. Succinate to furmarate -1 ATP is formed
D. Malate to oxaloacetate -1 ATP is formed

The enzyme involved in the first committed step of glycolysis is_____?

A. Phosphofructokinase
B. Glucose-6-Phosphatase
C. Hexokinase
D. Enolase

The end product of glycolysis under anaerobic conditions is______?

A. Lactic acid
B. Pyruvic acid
C. Acetoacetic acid
D. Oxaloacetic acid

Which of the following is a non-reducing sugar______?

A. Glucose
B. Maltose
C. Lactose
D. Sucrose

What high energy phosphate compound is formed in the citric acid cycle through substrate level phosphorylation_______?

A. ATP
B. TTP
C. ITP
D. GTP

The main enzyme responsible for activation of xenobiotics in (detoxification)___ ___?

A. Cytochrome P-450
B. Glutathione S-transferase
C. NADPH cytochrome P-450 reductase
D. Glucuronyl transferase

Which acid is formed in the citric acid cycle ?

A. Oxaloacetic acid
B. Glutamic acid
C. Nitric acid
D. None of the above

Kreb’s cycle occurs in _________ conditions?

A. Aerobic
B. Anaerobic
C. Microaerophilic
D. Aerobic and anaerobic

Which of them is multienzyme complex______?

A. Pyruvate dehydrogenase
B. Alpha ketoglutarate dehydrogenase
C. Succinate dehydrogenase
D. Enolase
E. Both A & B

Which of the following statement is TRUE? The hydrolysis of lactose yields glucose and galactose______?

A. The hydrolysis of lactose yields glucose and galactose
B. The hydrolysis of maltose yields glucose and fructose
C. The hydrolysis of sucrose yields only glucose
D. All of the above statements are true

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Biochemistry MCQs (Multiple Choice Questions) and Answers PDF

If you want to prepare tests for medical test examination then Biochemistry MCQs are very useful for  passing all initial tests. 

The compound that can give rise to glucose by gluconeogenesis is_____?

A. Acetyl CoA
B. Lactate
C. Palmitic acid
D. Fructose

Insulin acts on which enzyme in glycolysis ?

A. Glucokinase
B. Hexokinase
C. Glucose 6 phosphatase
D. Adenylate kinase

Adrenaline acts on which enzyme in glycogenolysis ?

A. Glucokinase
B. Hexokinase
C. Phosphorylase
D. Glucose diphosphatase

Gluconeogenesis occurs in the liver and _______?

A. Kidney
B. Muscle
C. Heart
D. Fat

Glycogen synthesis is increased by______?

A. Cortisone
B. Insulin
C. GH
D. Epinephrine

Which of the following is not a polymer of glucose?

A. Glycogen
B. Cellulose
C. Amylase
D. Inulin

The rate of absorption of sugars by the small intestine is highest for______?

A. Pentoses
B. Disaccharides
C. Polysaccharides
D. Hexoses

Biotin is required for the activity of_______?

A. Pyruvate carboxylase
B. Lactate dehydrogenase
C. Succinate thiokinase
D. Phosphohexose isomerase

Mutation in the oxidative enzymes (peroxisomes) could lead to________?

A. Zellweger’s syndrome
B. Gaucher’s disease
C. Epidermolysis bullosa
D. Leber’s neuropathy

Cofactor required for lipoprotein lipase activity is_____?

A. Apo A-II
B. Apo C-II
C. Apo C-III
D. Apo B-II

Inactive precursors of enzymes are known as_____?

A. Apoenzymes
B. Coenzymes
C. Proenzymes
D. Holoenzymes

Iron is present in all of the following except_______?

A. Myoglobin
B. Cytochrome
C. Catalase
D. Pyruvate kinase

Enzymes stored in muscle is______?

A. Alkaline phosphatase
B. SGOT
C. SGPT
D. CPK

Lactate dehydrogenase is______?

A. Isozyme
B. Coenzyme
C. Antienzyme
D. Zymogen

The combination of main supporting enzyme is called_____?

A. Apoenzyme
B. Coenzyme
C. Holoenzyme
D. Constitutive enzyme

Which of the following is a membrane bound enzyme that catalyzes the formation of cyclic AMP from ATP ?

A. Tyrosine kinase
B. Polymerase
C. ATP synthase
D. Adenylate cyclase

An example of layses is______?

A. Glutamine synthetase
B. Fumarase
C. Cholinesterase
D. Amylase

An enzyme that makes a double stranded DNA copy from a single stranded RNA template molecule is known as____________?

A. DNA polymerase
B. RNA polymerase
C. Reverse transcriptase
D. Phospho kinase

The enzymes that catalyses the same reaction but differ in physical properties are called as____?

A. Pro enzyme
B. Iso enzyme
C. Co-enzyme
D. Holoenzyme

In mycocarrdial infarction the first enzyme to rise_____?

A. CPK
B. LDH
C. SGOT
D. Amylase

Enzymes involved in degradation of epinephrine______?

A. Cholinesterase
B. Anticholinesterases
C. Catechol 0-transferase
D. Oxidases

Muscle glycogen cannot contribute directly to blood glucose level because___________?

A. Muscle lacks glucose 6 phosphatase
B. Muscle lacks phospho gluco isomerase
C. Absence of glucokinase
D. Muscle does not contain glycogen phosphorylase

The main site of fluoride inhibition in the Embden Meyerhof pathway of acid_______?

A. ATPase
B. Enolase
C. Pyruvate Kinase
D. Fructose 6 phosphatase

Enzymes help by______?

A. Lowering the activation energy
B. Increasing the substrate concentration
C. Decreasing the surface tension
D. Increasing the activation energy

The activity of the following enzyme is affected by biotin deficiency______?

A. Transketolase
B. Dehydrogenase
C. Oxidase
D. Carboxylase

The deficiency of thiamine can be identified by measuring the red cell______?

A. Transketaolase
B. Transaldolase
C. Alpha ketoglutarate dehydrogenase
D. Pyruvate dehydrogenase

Competitive enzyme inhibition will cause_______?

A. Decrease of km and increase of Vmax
B. increase of km and increase of Vmax
C. Decrease of km and decrease of Vmax
D. Increase of km and Unchanged of Vmax

Which of the following is correct of the pyruvate dehydrogenase enzyme complex ?

A. It is present in cytoplasm
B. Catalyzes the conversion of pyruvate to oxaloacetate
C. Requires TPP as cofactor
D. Catalyzes a reversible reaction

Dehydrogenase used as coenzymes all of the following, except____?

A. FMN
B. FAD
C. NADP+
D. Ferro protoporphyrin

Benzidine test is positive with the enzyme______?

A. Cytochrome oxidase
B. Dehydrogenase
C. Hydrolase
D. Peroxidase

Key glycolytic enzymes______?

A. Phosphofructokinase
B. Hexokinase
C. Pyruvate kinase
D. Glucose 1,6 diphosphatase

Multiienzyme complex in human______?

A. Fatty acid synthetase
B. Malonyl CoA carboxylase
C. Carbomoyl Phosphate synthetase
D. Adenosine phospho ribosyl transferase

Which of the following is NOT a characteristic feature of allosteric enzymes ?

A. They are multienzyme complex
B. Follow Michaelis-Menton Kinetics
C. Presence of Modulator site
D. Give sigmoid shaped curve

A example of a preventive antioxidant is______?

A. Catalase
B. Tocopherol
C. Superoxide dismutase
D. Urate

LDH has following number of lsoenzymes________?

A. 5
B. 3
C. 11
D. 2

One of the earliest symptoms of Vit. A deficiency is_____?

A. Nyctalopia
B. Xerophthalmia
C. Bitot’s spot
D. Keratomalacia

The enzyme phosphofructo kinase-1 is strongly activated by_____?

A. Cyclic AMP
B. Adenosine tri phosphate
C. Citrate
D. Fructose 2,6 bis phosphate

Megnesium is needed for the activity of which enzymes ?

A. Phosphatase
B. Aldolase
C. Dismutase
D. ATPase

When the prosthetic group of an enzyme is an inorganic ion, it is called a____?

A. Cofactor
B. Coenzyme
C. Apoenzyme
D. Holoenzyme

Coenzyme, in an enzymatic reaction usually functions to_______?

A. Activate the substrate
B. Increase the active sites of apoenzyme
C. Enhance the specificity of apoenzyme
D. Accept one of the cleavage products

The most common enzyme deficiency in man is______?

A. Glucose 6 phosphate dehydrogenase
B. Glucose 6 phosphatase
C. Hexokinase
D. Glucose 1,6 diphosphatase

Enzymes concerned with the citric acid cycle are found in______?

A. Nucleus
B. Mitochondria
C. Ribosomes
D. Non-particulate cytoplasm

Serum alkaline phosphatase level increase in_______?

A. Hypothyroidism
B. Carcinoma of prostate
C. Hyperparathyroidism
D. Myocardial infarction

The enzyme that splits hydrogen peroxide into water and oxygen is______?

A. Cytochromes
B. Cytochrome P 450
C. Super oxide dismutase
D. Catalase

Enzyme that catalyses the transfer of a molecule group from one molecule to another is______?

A. Oxidases
B. Peptidases
C. Transferases
D. LIpases

The activity of this plasma enzyme is responsible virtually for all plasma cholesterol esters in humans_____?

A. Lecithin cholesterol acyl transferase (LCAT)
B. Pyrophospho mevalonate decarboxylase
C. HMG CoA reductase
D. Phospho mevalonate kinase

Enzymes are classified according to_____?

A. Action on substrate
B. Action of coenzymes
C. Nature of the enzymes
D. All of the above

Fraction of CPK is an enzyme that is elevated in a myocardial infarct is_______?

A. MM fraction
B. MB fraction
C. BB fraction
D. Both MM and BB fraction

A material that speeds up a chemical reaction without chemically becoming involved is called_____?

A. A solvent
B. A base
C. A catalyst
D. Thermoplastic

Km of an enzyme is_____________?

A. Dissociation constant
B. The normal physiological substrate concentration
C. Substrate concentration at half maximal velocity
D. Numerically identical for all isozymes that catalyses a given reaction

Acetyl Co-A acts as a substrate for all the enzymes except______?

A. HMG-Co A synthase
B. Malic enzyme
C. Malonyl CoA synthetase
D. Fatty acid synthetase

The enzyme that is specifically increased in obstructive jaundice is____?

A. Glutamate oxaloacetate transaminase
B. Glutamate pyruvate transaminase
C. Alkaline phosphaase
D. Acid phosphatase

Elevated levels of serum glutamic oxaloacetic transaminase in indicative of______?

A. Deficiency of glutamic acid
B. Deficiency of oxaloacetic acid
C. Liver disease
D. All of the above

Muscle glycogen, which cannot contribute to blood glucose due to the absence of which enzymes ?

A. Phosphoglutamase
B. Branching enzyme
C. Debranching enzyme
D. Glucose-6-phosphotase

Michaelis-Menten hypothesis states that_____?

A. Rate of enzymatic reaction is independent of substrate concentration
B. Rate of non enzymatic reaction is proportional to substrate concentration
C. Km is the enzyme substrate complex association constant
D. Enzyme- substrate complex formation is essential in enzymatic reaction

Coenzyme responsible for single carbon transfer is_____?

A. Acetyl co enzyme A
B. Biotin
C. THF4
D. Pyridoxine

Hexokinase is a______?

A. Transferase
2. Reductase
3. Oxidoreductase
4. Oxidase

Enzyme + coenzyme constitutes_____?

A. Apoenzyme
B. Proenzyme
C. Protoenzyme
D. Holoenzyme

The amino acid required for the synthesis of haem is______?

A. Glutamine
B. Glutamic acid
C. Glycine
D. Lysine

Ubiqultin is involved in______?

A. Intracellular proteolysis
B. Electron transport chain
C. Transport of ATP
D. Protein folding

Which of the following is a function of the golgi apparatus ?

A. Modification of proteins
B. m RNA synthesis
C. Protein storage
D. t RNA synthesis

The most abundant protein present in body is_____?

A. Globulin
B. Albumin
C. Collagen
D. Hemoglobin

Oligosaccharide is_____?

A. Glucose
B. Gructose
C. Maltose
D. Dextrin

Synthesis of protein occurs on_____?

A. Mitochondria
B. Poly ribosomes
C. Nucleus
D. Golgi bodies

Bilirubin is produced from_____?

A. Haemoglobin
B. Myoglobin
C. Gall bladder
D. A & B

Bile contains_____?

A. Cholic acid
B. Chenodeoxycholic acid
C. Deoxycholic acid
D. Lithocholic acid
E. All of the above

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Biochemistry MCQs (Multiple Choice Questions) and Quizzes

If you are going to appear in the initial tests of Short Service Regular commission then following Biochemistry MCQs are very important before appearing in the tests. 

Nor epinephrine is converted to epinephrine by_____?

A. Dopamine hydroxylase
B. Dopa decarboxylase
C. O-methylation
D. N-methylation

Rate limiting step in adrenaline synthesis is conversion of______?

A. Tyrosine to dopa
B. Phenylalanine to tyrosine
C. Dopa to dopamine
D. Dopamine to nor epinephrine

Which of the following has a ketogenic effect on livers_____?

A. Insulin
B. Glucagon
C. GH
D. Androgen

Calcitonin is antagonist_____?

A. Parathyroid hormone
B. Thyroxine
C. Triidothyronine
D. Serotonin

Ribosomes are usually associated with_____?

A. Endoplasmic reticulum
B. Mitochondria
C. Nucleolus
D. Plasma membrane

Golgi bodies function are______?

A. Protein lipid synthesis
B. Protein synthesis
C. Sorting of glycoproteins
D. None of the above

Which cell organelle contains DNA_____?

A. Mitochondrion
B. Golgi body
C. Endoplasmic reticulum
D. Centriole

Most important compensatory mechanism in metabolic acidosis_____?

A. Hyperventilation
B. Increased NH3 excretion by kidneys
C. Increased urinary phosphates
D. Increased HCO3 Production

To keep blood PH at 7.4 the HCO₃ : H₂CO₃ ratio should be_____?

A. 20 : 1
B. 30 : 1
C. 15 : 1
D. 1 : 1

Normal blood PH is____?

A. 6.8 – 7.0
B. 7.0 – 7.12
C. 7.38 – 7.4
D. 7.7 – 8.0

Which of the following about biological membrane is true ?

A. Lipid moiety is amphipathic
B. Rigid assembly of protein, lipid and carbohydrate
C. Symmertrical bi leaflet structures
D. Lipid and protein moiety are held by covalent interactions

In Cytochrome p450, P stands for_____?

A. Structural proteins
B. Substrate proteins
C. Pigment
D. Polymer

Which of the following is false about starvation ketoacidosis ?

A. Metabolic acidosis
B. Smell of acetone in breath
C. Benedict’s test +ve
D. Rothera’s test is +ve

A relatively component of the electron transporting respiratory chain is_____?

A. Flavoprotein
B. Cytochrome Cl
C. Ubiquinone
D. Cytochrome A

During phagocytosis the metabolic process called respiratory burst involves activation of_____?

A. Oxidase
B. Hydrolase
C. Peroxidase
D. Dehydrogenase

Which of these organelle functions as the digestive system of the cell ?

A. Mitochondria
B. Rough endoplasmic reticulum
C. Golgi apparatus
D. Lysomes

Which one of the following human tissues contains the greatest amount of body glycogen ?

A. Liver
B. Kidney
C. Skeletal muscle
D. Cardiac muscle

Which of the following is inclusion of cytoplasm ?

A. Endoplasmic reticulum
B. Ribosome
C. Golgi body
D. Glycogen

Bile acids are formed from____?

A. Cholesterol
B. Aminoacids
C. Bilirubin
D. Lipoproteins

Normal blood bilirubin level is____?

A. 0.5 – 1 mg%
B. 1 – 3 mg%
C. 3 – 4 mg%
D. 4 – 5.5 mg%

Which of the following is precursor of adrenaline and thyroxine synthesis ?

A. Phenyl alanine
B. Tyrosine
C. Tryptophan
D. None of the above

The immediate precursor of norepinephrine is______?

A. Epinephrine
B. Tyrosine
C. Dopamine
D. Phenylalanine

The precursor of testosterone is______?

A. Aldosterone
B. Methyl testosterone
C. Estrogen
D. Pregnenolone

Which of the following is not a second messenger ?

A. c AMP
B. c GMP
C. Phosphatidyl inosital
D. Phosphatidyl glycerol

A balanced diet consists of_____?

A. 20% proteins, 25% fats, 50% carbohydrates
B. 20% proteins, 35% fats, 45% carbohydrates
C. 25% proteins, 25% fats, 50% carbohydrates
D. 35% proteins, 15% fats, 50% carbohydrates

Which of the organelles contain DNA_______?

A. Nucleus
B. Nucleolus
C. Golgi apparatus
D. Ribsomes

Cell membrane consists of____?

A. Lipids and proteins
B. Lipids only
C. Protein only
D. None of the above

The main function of mitochondria is_____?

A. Protein synthesis
B. Oxidation
C. Electron transfer
D. Fat synthesis

In ECF main electrolyte is_______?

A. Na+
B. K+
C. Cl
D. Proteins

The most important buffer in RBC is______?

A. O2 Hb +Na hemoglobinate
B. O2Hb +K hemoglobinate
C. H2CO3 + KHCO3
D. H2CO3 +NAHCO3

The major driving force for formation of membrane lipid bilayer is______?

A. Hydrogen bonding
B. Hydrophobic interactions
C. Vander wall forces
D. Not known

Detoxification or protective synthesis occurs by_______?

A. Oxidation
B. Reduction
C. Conjugation
D. Any of the above

Detoxification of drugs is controlled by_______?

A. Cytochrome
B. Cytochrome P450
C. Cytochrome C
D. Cytochrome A

Which of the following fatty acids are not synthesized in human body_______?

A. Oleic, linoleic and linolenic acid
B. Arachidonic, linolenic and linoleic acid
C. Palmitic Oleic and arachidonic
D. Linoleic, arachidonic and stearic acid

The lipoprotein particles that have the highest percentage concentration of cholesterol is_____?

A. Chylomicron
B. VLDL (Very low density lipoprotein)
C. LDL (Low density lipoprotein)
D. HDL (High density lipoprotein)

Fat provides ______% of body’s calories?

A. 40%
B. 30%
C. 50%
D. 75%

The normal level of serum cholesterol is_____?

A. 100-140 mgs/100 ml
B. 260-360 mgs/100 ml
C. 150-250 mgs/100 ml
D. 80-250 mgs/100 ml

The following is not a phospholipid_______?

A. Sphingomyelin
B. Lecithin
C. Cerebroside
D. Cephalin

Examples of monounsaturted fatty acids are____?

A. Oleic acid
B. Arachitlonic acid
C. Linolenic acid
D. Palmitic acid

The sugar component of cerebrosides is______?

A. Fructose
B. Sucrose
C. Galactose
D. None of the above

The lipid, which acumulates in fatty liver, is_______?

A. Triglycerides
B. FFA
C. Lipoprotein
D. Cholesterol

The product of oxidation of odd chainfatty acids is______?

A. Aceto acetyl CoA
B. Malonyl CoA
C. Propionyl CoA
D. Fumaryl CoA

The substance essential for transfter of fatty acids across mitochondrial membrance____?

A. Creatine
B. Creatinine
C. Carnitine
D. Coenzyme A

Ketone bodies are normally synthesized from_____?

A. Acetyl-CoA
B. Glucose
C. Glycerol
D. Acetone

Ketone bodies are by products of metabolism of____?

A. Carbohydrate
B. Protein
C. Fat
D. All of the above

The ketone bodies, which are excreted in diabetic ketoacidosis ?

A. Acetoacetic acid and pyruvic acid
B. Acetoacetic acid and oxalocacetic acid
C. Acetoacetic acid and alpha ketoglutaric acid
D. Acetoacetic acid and beta hydroxyl butyric acid

Rate limiting step in cholesterol synthesis is_______?

A. HMG CoA synthetase
B. HMG CoA lyase
C. HMG CoA reductase
D. Mevalonate synthetase

Which is not seen in HMG CoA pathway ?

A. Pyruvate
B. Cholesterol
C. Mevalonate
D. Acetyl CoA

The precursor of steroid is_______?

A. Amino acids
B. Fatty acids
C. Cholesterol
D. None of the above

Lipid from tissue is carried to liver by____?

A. LDL
B. VLDL
C. HDL
D. Chylomicrons

Triglycerides in serum are transported by_______?

A. HDL
B. VLDL
C. LDL
D. Chylomicrons

Prostaglandin synthesis is partially switched off by______?

A. Lipo oxygenase inhibition
B. Cyclo-oxygenase inhibition
C. Reductase
D. Peroxidase

Triglyceride synthesis synthesis is increased by______?

A. Growth hormone
B. Insulin
C. Cortisol
D. Gulcagon

The total blood concentration of ketone bodies in well fed individual is____?

A. 1 mg%
B. 5 mg%
C. 12 mg%
D. 20 mg%

High content of cholesterol is present in______?

A. Coconut oil
B. Egg yolk
C. Hydrogenated fat
D. Ghee (unsaturated)

Insulin caused lipogenesis by all except______?

A. Increasing acetyl-CoA corboxylase activity
B. Increases the transport of glucose in to the cells
C. Inhibits Pyruvate dehydrogenase
D. Decreases intracellular cAMP level

The main pathway for De – Novo synthesis of fatty acids occurs in______?

A. Mitochondria
B. Nucleus
C. Cytosol
D. None of the above

Adipose tissue releases free fatty acids in the________?

A. Fasting state
B. Resting state
C. Active state
D. All of the above

Increase in lactate and pyruvate is seen in deficiency of________?

A. Pyridoxin
B. Niacin
C. Thiamine
D. Retinotic acid

The main function of HDL is______?

A. Transport cholesterol from liver to peripheral tissues
B. Esterification with PUFA
C. Both of the above
D. None of the above

Acetyl CoA is produced from which fuel sources_____?

A. Carbohydrate
B. Lipid
C. Amino acids
D. All of the above

The reducing equivalent for fatty acid synthesis is derived form______?

A. Glycolysis
B. Kreb’s cycle
C. Urea cycle
D. Pentose phosphate pathway

Lipid is required in the average diet because it________?

A. has a high caloric value
B. Provides essential fatty acid
C. aids in absorption of carbohydrates
D. is necessary for storage of carbohydrates

Fatty aids help in synthesis of all except____?

A. Glucose
B. Cholesterol
C. Ketone bodies
D. Fat

The human plasma lipoprotein containing the highest percentage of triacylglycerol by weight is_____?

A. VLDL
B. Chylomicrons
C. HDL
D. LDL

B-oxidation of odd-chain fatty aids produce_______?

A. Succinyl CoA
B. Propionyl CoA
C. Acetyl CoA
D. Malonyl CoA

True about prostaglandins is____?

A. Short acting
B. Present in many tissues
C. Some require C-AMP for their action
D. All are true

Biochemistry MCQs for Preparation for AMC, AFNS

Following Biochemistry MCQs must be read before registering yourself in the Army Medical Tests or Armed Force Nursing Students Tests. 

Endogenous triglycerides in plasma is maximally bound to______?

A. Chylomicrons
B. LDL
C. VLDL
D. HDL

HMG CoA reductase is inhibited by______?

A. Clofibrate
B. Gemfibrosil
C. Lovastatin
D. cholestyramine

HMG-CoA is formed during metabolism of all except_______?

A. Cholesterol
B. Leucine
C. Ketone bodies
D. Bile acids

The precursor of cholesterol synthesis is_______?

A. Acetic acid
B. Acetyl CoA
C. Oxalo acetic acid
D. Pyruvate

All are derived of cholesterol except_____?

A. Chenodeoxy cholic acid
B. Glycocholic acid
C. Testosterone
D. Cholecystokinin

Which of the following organs cannot use ketone bodies______?

A. Brain
B. Liver
C. Kidney
D. Spleen

Which of the following is not a ketone body____?

A. Acetone
B. Acetic acid
C. Acetocetate
D. Beta hydroxybutyric acid

Ketone body formation takes place in_____?

A. Liver
B. Kidney
C. Spleen
D. Blood

NADPH is required for________?

A. Gluconeogenesis
B. Glycolysis
C. Fatty acid synthesis
D. Glycogenolysis

Limiting factory for fatty acid synthesis______?

A. Aceto acetate synthetase
B. Acyl transferase
C. Acetyl CoA carboxylase
D. Biotin

In Niemann-Pick’s disease the following subs trance accumulate in CNS in excess______?

A. Glycerophosphatides
B. Phosphoinositides
C. Phosphosphingosides
D. Glycerosphingosides

Which of the following is a phospholipid_______?

A. Glycogen
B. Sphingomyelin
C. Prostaglandin
D. Oleic acid

Unsaturated fatty acids are converted to_______?

A. Prostaglandins
B. Cholesterol
C. Cell membrane lipid
D. Saturated fatty acid

Saponification means hydrolysis of fats by_______?

A. Acid
B. Alkali
C. Water
D. Enzymes

The major lipids that make up the cell membrane are______?

A. Triglycerides
B. Phospholipids
C. Sphingomyelins
D. Fatty acids

The most important role of cholesterol is______?

A. It is a component of cell membrane
B. It is a precursor of polyunsaturated fatty acids
C. It stores up energy
D. None of the above

A fatty acid that is not synthesized in man is_____?

A. Linoleic acid
B. Oleic acid
C. Palmitic acid
D. Stearic acid

Fatty acid oxidation occurs in______?

A. Cytoplasm
B. Microsomes
C. Mitochondria
D. All of the above

True about G protein couple receptors is _______ ?

A. G proteins bind to hormones on the cell surface
B. All the three subunits alpha, beta and gamma should bind each other for G protein to act
C. G Proteins act as inhibitory and excitatory because of difference in alpha subunit
D. G protein is bound to GTP in resting state

Non polar lipid act as_____?

A. Electrical insulators
B. Irons
C. Non electrical insulators
D. Electrolytes

Iron is present in all, EXCEPT________?

A. Myoglobin
B. Cytochrome
C. Catalase
D. Pyruvate kinase

Which is the poorest source of calcium among the following________?

A. Rice
B. Human milk
C. Egg yolk
D. Cow’s milk

Transport form of iron is______?

A. Transferrin
B. Ferritin
C. Apoferritin
D. Lactoferrin

Which of the following is the best site of absorption of calcium ?

A. Proximal segment of small intestine
B. Middle segment of small intestine
C. Ascending colon
D. Ileum

During phagocytosis, the metabolic process called respiratory burst involves the activation of______?

A. Oxidase
B. Hydrolase
C. Peroxidase
D. Dehydrogenase

The transmembrane adhesive molecules present in hemi desmosomes which specifically binds to basal lamina glycoprotein laminin are______?

A. Integrin a6-B4
B. The catenins desmoplakin
C. cadherins desmoglein
D. a and B catenin

Under metabolic conditions associated with a high rate of fatty acid oxidation liver produces______?

A. Glutamate
B. Acetoacetate
C. Cholesterol
D. Glycine

The fluid mosaic model of membrane structure was proposed by______?

A. Watson and Crick
B. Edwarg Angle
C. G.V Black
D. Singer and Nicolson

Free radicals can be inactivated by the following enzymes EXCEPT_______?

A. Glutathione peroxidase
B. Catalase
C. Superoxide dismutase
D. Myeloperoxidase

The best technique useful for initial viral load estimation is______?

A. Real time PCR
B. Widal test
C. Electrophoresis
D. Immunofluoresence

FSH, LH, TSH acts through_______?

A. Cyclic AMP
B. Cyclic GMP
C. Adenosine cyclate
D. Calcium release

If bile acid recycling time is short, then bile salt reservoir pool will be_____?

A. Increased
B. Decreased
C. Uchanged
D. Has no effect

Somatomedin mediates_______?

A. Deposition of chondroitin sulfate
B. Lipolysis
C. Gluconeogenesis
D. Decreased rate of glucose uptake by cells

Ligant for peroxisome proliferation activating receptor (PPAR) receptors, a group of nuclear hormone receptors that are involved in the regulation of genes related to glucose and lipid metabolism is_______?

A. Repaglinide
B. Voglibose
C. Exanatide
D. Rosiglitgazone

Cholesterol levels in abnormal person should be preferably less than_______?

A. 200 mg/dl
B. 180 mg/dl
C. 150 mg/dl
D. 120 mg/dl

Hyponatremia is defined as a serum Na+ level _______?

A. < 135 mmol/L
B. >135 mmol/L
C. < 160 mmo/L
D. < 100 mmo/L

Generation of free radicals occurs by all of the following mechanism EXCEPT_____?

A. Normal metabolism
B. Oxygen toxicity
C. Reperfusion after ischemic injury
D. All of the above

The antibacterial substance present in tears which acts by splitting cell wall components is_______?

A. Penicillin
B. Lysozyme
C. Betalysine
D. Lactoperoxidase

Glycemic index of a starchy food is a measure of its______?

A. Energy
B. Utility
C. Collectivity
D. None of the above

All are components of basement membrane except_______?

A. nidogen
B. Laminin
C. Eutactin
D. Rhodopsin

A patient of type 2 diabetes mellitus is given nutrition rich in______?

A. Proteins
B. Carbohydrates
C. Fat
D. Fibre rich diet

Which of these is not included in parenteral therapy ?

A. Carbohydrates
B. Fibres
C. Fats
D. Micronutrients

Free radicals are chemical species which have_____?

A. Single unpaired electron in an outer orbit
B. Single paired electron in an outer orbit
C. Double unpaired electron in an outer orbit
D. Double paired electron in an outer orbit

In the physiological system, nitric oxide is known to act through_______?

A. Cyclic AMP
B. Calcium ions
C. Cyclic GMP
D. Prostacyclins

True about denaturation of protein is all except______?

A. Unfolding occurs
B. Disruption of secondary structure occurs
C. Sequence of amino acids remain the same
D. Biological activity is retained

Within the RBC hypoxia stimulates glycolysis by which of the following regulating pathways ?

A. Hypoxia stimulates pyruvate dehydrogenase by increased, 2, 3DPG
B. Hypoxia inhibits hexokinase
C. Hypoxia stimulates release of all glycolytic enzymes from Band 3 on RBC membrane
D. Activation of the regulatory enzymes by high PH

The abundant glycoprotein in the basement membrane and has binding domain for both ECM and cell-surface receptor is______?

A. Laminin
B. Fibronectin
C. E – Cadherins
D. Tenascin

Normal serum alkaline phosphatase level is______?

A. 100-400 Bodansky units
B. 1000-4000 Bodansky units
C. 0.1-0.4 Bodansky units
D. 1-4 Bodansky units

The following are derived from cholesterol, EXCEPT______?

A. Bile acids
B. Steroid hormones
C. Vitamin D
D. Energy

Enzyme regulating the conversion of ethanol to acetaldehyde______?

A. Alcohol dehydrogenase
B. Acetaldehyde dehydrogenase
C. Catalase
D. Enolase

The normal range of serum osmolality (in mosm/L) is______?

A. 280 to 295
B. 300 to 320
C. 350 to 375
D. 200 to 250

The fuel value of fat is______?

A. 4
B. 7
C. 9
D. 5

Heme is converted to bilirubin mainly in_____?

A. Kidney
B. Liver
C. Spleen
D. Bone marrow

In molecular cloning, Blue White screening is used for____?

A. To screen for recombinant vectors
B. To detect gene mutations
C. To identify desired chromosomal DNA insert in plasmid vectors
D. To detect host DNA in situ

Enzymes increase reaction rates by________?

A. Altering the free energy of the action
B. Inhibiting the backward reaction
C. Enhancing the forward reaction
D. Decreasing the energy of activation

Which of the following is most important content of diet ?

A. Protein
B. Water
C. Vitamin
D. Minerals

In all the following RNA participates directly except_______?

A. Post translation modification
B. Post transcriptional modification
C. DNA replication
D. Splicing

Normal level of serum phosphorous is______?

A. 2.5 – 4.5 mgm%
B. 7-9 mgm%
C. 40-50 mgm%
D. 1-2 mgm%

Inside the cell, the substance, which contributes to most of the osmolality, is________?

A. Protein
B. Potassium
C. Urea
D. Phosphate

Daily requirement of iron in man is_____?

A. 1gm
B. 10 microgram
C. 10 mg
D. 20 mg

In human body which of the following trace element is next to iron______?

A. Ca++
B. Zn++
C. Cu++
D. Selenium

Ferritin – an inactive form of iron is stored in_______?

A. Gut
B. Spleen
C. Liver
D. All of the above

Peroxidase enzyme contain________?

A. Chromium
B. Selenium
C. Magnesium
D. Calcium

Translation occurs at_______?

A. Mitochondria
B. Centrosome
C. Nucleus
D. Ribosome

Chargaff rule states that____?

A. A+G=T+C
B. A/T=G/C
C. A=U=T=G=C
D. A+T=G+C

Introduction to Biochemistry MCQs with Answers PDF

Codons are present on______?

A. m-RNA
B. DNA
C. t-RNA
D. Ribosomal RNA

The portion of DNA in Which RNA polymerase binds and starts transcription is called______?

A. Terminator
B. Anti terminator
C. Operator
D. Promoter region

End product of purine metabolism is______?

A. Creatinine
B. Uric acid
C. Xanthine
D. Phosphates

All are true of the genetic code except______?

A. Degenerate
B. Universal
C. Punctuation
D. Non overlapping

R-RNA is mainly produced mainly in_____?

A. Nucleus
B. Nucleolus
C. Ribosome
D. Endoplasmic reticulum

On complete hydrolysis of DNA we will get all the following except_______?

A. Deoxy pentose sugar
B. Phosphoric acid
C. Adenosine
D. Purine bases

Denaturation of double stranded DNA involves______?

A. It gets broken down to nucleotides
B. It becomes single stranded reversibly
C. It becomes single stranded irreversibly
D. It becomes double stranded irreversibly

Which of the following is used in recombinant DNA technology ?

A. Restriction endonucleases
B. PCR
C. Reverse transcriptase FISH
D. None of these

Transcription is the synthesis of______?

A. Single stranded complimentary copy of DNA
B. Double stranded complimentary copy of DNA
C. Complimentary copy of RNA
D. COmplimentary copy of rRNA

Serum creatine kinase-3 (CK-3) is elevated in_______?

A. Muscular dystrophy
B. Myocardial infarction
C. Alcoholic cirrhosis
D. Brain tumours

Ammonia produced by brain is trapped as_____________?

A. Urea
B. Uric Acid
C. Creatinine
D. Glutamine

The patient suffered from hypogondism, failure to thrive, lose of taste and unable to maintain stability. This shows the deficiency of_____?

A. Zinc
B. Chromium
C. Copper
D. Potassium

The sigma subunit of prokaryotic RNA polymerase_______?

A. Binds the antibiotic Rifampicin
B. Is inhibited by a-amanitin
C. Specifically recognizes the promoter site
D. Is part of the core enzyme

Iron absorption is decreased in presence of all except_____?

A. Phytates
B. Ascorbic acid
C. Tannins
D. Phosphates

Normal serum calcium level is_____?

A. 4-6 mg/dl
B. 9-11 mg/dl
C. 19-21 mg/dl
D. 20-30 mg/dl

The normal value of serum potassium level is_____?

A. 2.8-3.8 meq/L
B. 3.8-5 meq/L
C. 5-5.8 meq/L
D. 6-7.2 meq/L

Highest binding of iron in plasma is seen with______?

A. Transferrin
B. Ferritin
C. Hemoglobin
D. Ceruloplasmin

Kinase requires______?

A. MN++
B. Cu++
C. Mg++
D. Inorganic phosphate

Mutations are due to changes in_____?

A. DNA nucleotide sequence
B. RNA nucleotide sequence
C. Amino acid sequence of ribonuclease
D. Cell walls

The initiation codon for protein synthesis is_____?

A. AUG
B. UAA
C. UUU
D. UAG

Nonsense codons bring about______?

A. Elongation of polypeptide chain
B. Pre-translational modification of protein
C. Initiation of protein synthesis
D. Termination of protein synthesis

Unwinding of DNA is done by____?

A. DNAse
B. Topo isomerase
C. Ligase
D. Reverse transcriptase

Which of the following process in involved in conversion of DNA to RNA_____?

A. Conjugation
B. Transduction
C. Translocation
D. Transcription

Restriction endonuclease cleaves______?

A. Double stranded DNA
B. SIngle stranded DNA
C. SIngle stranded RNA
D. Polypeptide

Genes are______?

A. Ribonucleic acid
B. Deoxy ribonucleic acid
C. Lipoproteins
D. Chromo proteins

DNA double helix is bound by_______?

A. Covalent bond
B. Hydrogen bond
C. Disulfide linkage
D. Vander wall forces

Which base is not found in DNA________?

A. Adenine
B. Guanine
C. Cytosine
D. Uracil

In the body, metabolism of 10 g of protein would produce approximately______?

A. 1 Kcal
B. 41 Kcal
C. 410 Kcal
D. 4100 Kcal

Alkaptonuria an inherited metabolic disorder is due to the deficiency of_______?

A. Homogentisate oxidase
B. Cystathionase
C. Pheylalanine hydroxylase
D. Tyrosine transaminase

Colloidal osmotic pressure of plasma is by______?

A. Albumin
B. Fibrinogen
C. Globulin
D. Prothrombin

The daily requirement of protein for the adults is_______?

A. 6 gms
B. 60 gms
C. 120 gms
D. 250 gms

The fastest moving fraction of protein in serum When subjected to paper electrophoresis is_____?

A. Albumin
B. Alpha 1 globulin
C. Beta Globulin
D. Gamma Globulin

Most common non protein nitrogenous fraction of blood_____?

A. Urea
B. Uric acid
C. Urobilinogen
D. Creatinin

Proteins are linear polymers of amino acids, They fold into compact structures Sometimes these folded structures associate to form homo or hetero dimers Which one of the following refers to this associated form ?

A. Denatured state
B. Molecular aggregation
C. Precipitation
D. Quaternary structure

The protein rich in basic amino acids, which functions in the packaging of DNA is chromosomes is______?

A. Histone
B. Collagen
C. Hyaluronic acid binding protein
D. Fibrinogen

Which of the following is not a post transcriptional modification of RNA ?

A. Splicing
B. 5′ capping
C. 3′ polyadenylation
D. Glycosylation

Thyroxine and catecholamines are derived from_______?

A. Tyrosine
B. Tryptophan
C. Alanine
D. Leucine

In Hartnup’s disease _______ is excreted in the urine?

A. Ornithine
B. Glutamine
C. Tryptophan
D. Phenylalanine

Which of the following is not a part of hemoglobin molecule_______?

A. Pyrrole rings
B. Vinyl groups
C. Histidine
D. Ferric ions

Proteins are absorbed from GIT as______?

A. Amino acids
B. Peptides
C. Peptones
D. All of the above

Which of the following is a precursor of protoporphyrin______?

A. Alanine
B. Leucine
C. Histidine
D. Glycine

Cytochromes are______?

A. Pyridine nucleotides
B. Riboflavin containing nucleotides
C. Metal containing flavoproteins
D. Iron-porphyrin proteins

Heme in haemoglobin is_____?

A. Between Helix C and D
B. Surrounded by non polar environment
C. Bonded to E7 histidine
D. Protoporophyrin IX

Which of the following is correct about breakdown of hemoglobin (Hb)___ ___?

A. Hb→Heme→bilirubin→Urobilinogen
B. Heme→Hb→Biliverdin→Urobilinogen
C. Hb→Heme→Bilverdin→Uro bilinogen
D. Hb→Heme→bilirubin→Urobilinogen→Biliverdin

Creatine is formed metabolically from_____?

A. Tryptophan
B. Arginine
C. Phenylalanine
D. Histidine

Major source of ammonia in the kidney is_____?

A. Urea Aspartate
B. Aspartate
C. Glutamine
D. Glutamate

Key enzyme in urea synthesis is____?

A. Urease
B. Carbamyl synthetase
C. Arginase
D. Ornithine

Ammonia is detoxified in liver to form______?

A. Uric acid
B. Glutamine
C. Creatinine
D. Urea

A small Ca+2 binding protein that modifies the activity of many enzymes and other proteins in response to changes of Ca+2 concentration is known as______?

A. Cycline
B. Calmodulin
C. Collagen
D. Kinesin

Decarboxylation of which of the following amino acids results in formation of a vasodilator ?

A. Valine
B. Arginine
C. Histidine
D. Glutamic acid

A mutation that converts an amino acid codon to a stop codon is a______?

A. Nonsense mutation
B. Transversion
C. Silent mutation
D. Frame shift mutation

Histidine is converted to histamine by_______?

A. Transamination
B. Hydroxylation
C. Decarboxylation
D. Reduction

ALbumin is synthesized by_____?

A. Liver
B. Kidney
C. Muscle
D. Spleen

Which of the following amino acids is quickly converted to tyrosine ?

A. Arginine
B. Glycine
C. Phenylalanine
D. Leucine

Synthesis of protein occurs on_____?

A. Mitochondria
B. Poly ribosomes
C. Nucleus
D. Golgi bodies

Which of the following is present in the plasma but absent in the serum ?

A. Albumin
B. Globulin
C. Lecithin
D. Firbinogen

The amino acid, which is used is the estimation of collagen is______?

A. Hydroxyproline
B. Proline
C. Lysine
D. Glycine

The amino acid from which niacin is synthesized is_____?

A. Tyrosine
B. Theronine
C. Tryptophan
D. Histidine

Hydroxylation of proline require the following except______?

A. Fe+2
B. O₂
C. Ascorbic acid
D. Succinate

The process by which a base sequence of messenger RNA is synthesized (by a RNA polymerase) on a template of complementary DNA is called______?

A. Transcription
B. Transduction
C. Translation
D. Translocation

The major fuel for the brain after several weeds of starvation_______?

A. Glucose
B. Fatty acid
C. Beta hydroxy butyrate
D. Glycerol

Non essential amino acids are not______?

A. Used by the body
B. Forming part of the proteins
C. Required in the diet
D. Absorbed in the intestines

The following is false about tryptophan______?

A. Non-essential amino acid
B. Involved in serotonin synthesis
C. Involved in niacin synthesis
D. Involved in melatonin in synthesis

Which of the following amino acid is involved in gluconeogenesis_______?

A. Glycine
B. Valine
C. Cysteline
D. All of the above

Glycine is present in______?

A. Hemoglobin
B. Glutathione
C. Purines
D. Creatine
E. All of the above

Biochemistry MCQs (Multiple Choice Questions) for Short Service Regular Commission

Quaternary structure of protein is______?

A. The arrangement sequence of amino acids in the polypeptide chain
B. Inter relation between amino acids in a single polypeptide chain
C. Inter relation of amino acids in 2 polypeptide chains
D. The inter relation and arrangement of polypeptides in a protein with more than 2 polypeptide chains

Which of the following is a derived a derived protein______?

A. Protamines
B. Peptones
C. Prolamines
D. Lactalbumin

All are genetic amino acid deficiency disease except______?

A. Phenyl ketonuria
B. Alkaptonuria
C. Homocystinuria
D. 6alactosemia

Mannose 6 phosphate containing freshly synthesized proteins are directed to______?

A. Nucleus
B. Lysosomes
C. Mitochondria
D. Golgi apparatus

Glutamine replaced by valine in sckle cell anaemia is characterized_____?

A. Non Sense mutation of beta chain
B. Missense mutation of beta chain
C. Degradation of beta chain
D. Deletion of beta chain

All are true about glutathione except ?

A. It is a tripetide
B. It converts hemoglobin to methemoglobin
C. It conjugates xenobiotics
D. It scavenges free radicals and superoxide ions

The class of amino acids that contains only non essential amino acids is______?

A. Acidic
B. Basic
C. Aromatic
D. Branched chain

The nitrogen content in 50 gm of a typical dietary protein is most likely to be_______?

A. 5 gm
B. 8 gm
C. 10 gm
D. 16 gm

The number of essential amino acid are______?

A. 6
B. 8
C. 12
D. 16

The amino acid residue having animino side chain is______?

A. Lysine
B. Histidine
C. Tyrosine
D. Proline

The primary role of chaperones is to help in_____?

A. Protein synthesis
B. Protein degradation
C. Protein denaturation
D. Protein folding

Argentaffinoma is characterized by excess excretion of______?

A. 5- Hydroxy indole acetate
B. 3- Hydroxy phenyl pyruvate
C. Phenyl lactate
D. Phenyl acetate

Urea is formed in_______?

A. Brain
B. Kidney
C. Liver
D. Intestine

The following is not a carrier protein______?

A. Cerruloplasmin
B. Transferrin
C. Transcobalamine
D. Haptoglobulin

False statement about haemoglobin structure______?

A. Hb has 2 polypeptide chains
B. Iron is present in ferrous state
C. Hb structurally similar to myoglobin
D. Ferrous ions are in porphyrin rings

At PH 7 the binding of 2,3 DPG to hemoglobin occurs at which site ?

A. Sulphydryl group
B. Carboxy terminal
C. Amino terminal
D. Histidine

Iron is complexed in hemoglobin to_______?

A. Leucine
B. Histidine
C. Isoleucine
D. Valine

Urea is produced by the enzyme_______?

A. Urease
B. Uricase
C. Arginase
D. Glutaminase

Urinary protein is detected by______?

A. Barfoed test
B. Hay’s test
C. Boiling test
D. Ehrlich’s test

Which is the by product of the urea cycle______?

A. Aspartate
B. Succinate
C. Ornithine
D. Fumarate

Amino acids excreted in the urine in cystinosis______?

A. Cystine
B. Ornithine
C. Arginine
D. Lysine
E. All of the above

Albinism is a genetic disease that results in incomplete metabolism of_____?

A. Histidine
B. Cystine
C. Tyrosine
D. Alanine

All of the following are globular proteins except______?

A. Prolamines
B. Albumin
C. Globulin
D. Myosin

Which one of the following amino acids is purely ketogenic ?

A. Proline
B. Phenylalanine
C. Isoleucine
D. Leucine

Collagen is rich in_____?

A. Glutamate and glycine
B. Alanine and glycine
C. Proline and glycine
D. Glutamate and proline

Digestion of proteins is initiated by_______?

A. Amylase
B. Sucrase
C. Chymotrypsin
D. Pepsin

The nitrogen of the body is supplied by______?

A. Triacyl glycerol
B. Proteins
C. Glucose
D. Lipids

Alkaptonuria, an inherited metabolic disorder of L0tyrosine metabolism is due to lack of_______?

A. Parahydroxy phenyl pyruvate Hydroxylase
B. Tyrosine transaminase
C. Homogentisate oxidase
D. Tyrosine oxidase

One of the following is not an amino acid_______?

A. Glycine
B. Hydroxy proline
C. Glutamic acid
D. Choline

Precursor of melanin is________?

A. Phenylalanine
B. Tryptophan
C. Tyrosine
D. Methionine

The reducing end of glutathione, the amino acid is____?

A. Glycine
B. Leucine
C. Lycie
D. Valine

Following are the essential amino acid______?

A. Phenylalanine, Tryptophan lysine
B. Phenylalanine, Arginine Methinonine
C. Phenylalanine, Valine, Glycine
D. Histidine, Glutamine, Valine

The process of transfer of information from the RNA to the proteins is called_______?

A. Mutation
B. Translation
C. Transcription
D. Conjugation

Following is non-essential amino acid_______?

A. Phenylalanine
B. Proline
C. Tryptophan
D. Threonine

One of the following is nonessential amino acid_______?

A. Tyrosine
B. Valine
C. Methionine
D. Cystine

Aromatic ring is present in______?

A. Arginine
B. Glycine
C. Phenylalanine
D. Phenylalanine, Glycine

In maple syrup urine disease the amino acids excreted in the urine are______?

A. Leucine
B. Isoleucine
C. Valine
D. All of the above

Indole ring is present in_____?

A. Tryptophan
B. Valine
C. Methionine
D. Histidine

Biuret test is confirmatory test for______?

A. Protein
B. Fat
C. Carbohydrate
D. None of the above

Albumins and globulins are ________ proteins?

A. Simple
B. Peptones
C. Prolamines
D. Lactalbumin

Tertiary structure of protein is maintained by all except______?

A. H2 bond
B. Hydrophobic
C. Ionic bond
D. Disulphide bond
E. None of the above

Vitamin C effects_______?

A. Maturation of procollagen
B. Formation of osteoid matrix
C. Calcification of osteoid
D. Both A and B

Cereals are deficient in_______?

A. Vitamin C
B. Vitamin B complex
C. Iron
D. Calcium

The vitamin K dependent proteins C and S are characterized by their ability to inactivate factor_____?

A. VIII a and V a
B. VIII a
C. V a
D. None of the above

Who is known for his work on scurvy ?

A. Fracastorius
B. James lind
C. John snow
D. Edward Jenner

Aniacinosis results in_______?

A. Perleche
B. Beri beri
C. Pellagra
D. Nyctalopia

Biotin is required for the activity of_______?

A. Pyruvate carboxylase
B. Lactate dehydrogenase
C. Succinate thiokinase
D. Phosphohexose isomerase

All of the following are true about manifestations of vitamin E deficiency except_______?

A. Hemolytic anemia
B. Posterior column abnormalities
C. Cerebellar ataxia
D. Autonomic dysfunctions

Both Vitamin K and C are involved in______?

A. The synthesis of clotting factors
B. Post translational modifications
C. Antioxidant mechanisms
D. The microsomal hydroxylation reactions

Thiamine deficiency can be diagnosed by measuring______?

A. Thiamine levels in blood
B. Alkaline phosphatase levels in blood
C. Transketolase activity in RBC
D. Plasma pyruvate and lactic acid levels

Vitamin B12 is_______?

A. Extrinsic factor of castle
B. Intrinsic factor of castle
C. Cyano cobalamine
D. A fat soluble vitamin

Sources of the nucleotide portion of NAD include______?

A. N-methyl nicotinamide
B. Riboflavin
C. PRPP
D. Tryptophan

Consumption of raw egg white in the diet may result in the deficiency of________?

A. Riboflavin
B. Biotin
C. Thiamine
D. Pyridoxine

Peripheral neuropathy due to deficiency of vitamin is seen with_______?

A. Pyridoxine
B. Vit E
C. Vit A
D. Pantothenic acid

Deficiency of vitamin C causes the following except______?

A. Defective collagen synthesis
B. Soft swollen gums
C. Pigeon chest
D. Subcutaneous & other hemorrhage

FIGLU excretion test is to estimate deficiency of________?

A. Vitamin K
B. Vitamin B6
C. Vitamin folic acid
D. Niacin

Avidin influences which of the following vitamins ?

A. Biotin
B. Niacin
C. Thiamine
D. Phylloquinone

Which of the following are the sources of Vit C_______?

A. Apple
B. Fresh green vegetables
C. Citrus fruits
D. Both B and C

Niacin & riboflavin help in_____?

A. Redox reactions
B. Transamination reaction
C. Methyl group transfer
D. Amine group transfer

Collagen formation is affected in deficiency of_____?

A. Vit A
B. Vit C
C. Vit B2
D. Vit D

Angular cheilosis is frequently associated with deficiency of_______?

A. Thiamine
B. Riboflavin
C. Niacin
D. Folic acid

The amino acid from which niacin synthesized is_______?

A. Tyrosine
B. Tryptophan
C. Threonine
D. Histidine

Coenzyme A contains which of the following vitamins_______?

A. Biotin
B. Pyridoxine
C. Pantothenic acid
D. Niacin

Which of the following is the poorest source of vitamin C ?

A. Milk
B. Cabbage
C. Guava
D. Radish

Pernicious anaemia occurs in_____?

A. Vit B1 deficiency
B. Vit B12 deficiency
C. Vit C deficiency
D. Vit D deficiency

Vitamin associated with one carbon transfer is______?

A. Niacin
B. Thiamine
C. Ascorbic acid
D. Folic acid

Biochemistry MCQs for Preparation of Short Service Regular Commission 

In the following, past papers questions of Biochemistry MCQs are available which helps to have clear idea about the initial academic tests of Short Service Commission. 

Average daily dose of vitamin C is______?

A. 30 – 40 mg
B. 50 – 60 mg
C. 60 – 100 mg
D. 100 – 150 mg

Xerophthalmia is caused by______?

A. Vitamin A deficiency
B. Vitamin D deficiency
C. Vitamin C deficiency
D. Vitamin K deficiency

Which of the following factors delay wound healing______?

A. Vitamin B12 deficiency
B. Ascorbic acid deficiency
C. Infection
D. B & C option

Ascorbic acid_______?

A. Is a reducing agent
B. Decrease iron absorption
C. Is harmless in high doses
D. Is requirement for lysyl oxidase

Tocopherol is associated with______?

A. Vitamin A
B. Vitamin E
C. Vitamin K
D. Vitamin D

The action of vitamin K in formation of clotting factor is through______?

A. Post transcription
B. Post translation
C. Golgi complex
D. Endoplasmic reticulum

Which of the following is not true of Vit D______?

A. Its active form is calcitriol
B. Increase calcium absorption from the intestines
C. Its deficiency results in rickets
D. Its decrease cause phosphate reabsorption from the kidneys

Most of vitamin B12 in the body is stored as______?

A. Methyl B12
B. Hydroxy B12
C. Cyano cobalamine
D. None of the above

The following vitamin is important in non-oxidative decarboxylation, transamination and transsulfuration reactions_______?

A. Riboflavin
B. Thiamine
C. Pyridoxine
D. Pantothenic acid

Vitamin C is present in largest amount in the body in_____?

A. Eye
B. Kidneys
C. Testes
D. Adrenal cortex

Tryptophan load test helps in the evaluation of deficiency of the vitamin______?

A. Folic acid
B. Niacinamide
C. Pyridoxine
D. Cyano cobolamine

Which vitamin is related to a co-factor in glycine metabolism is_______?

A. Vit E
B. Folic acid
C. Thiamine
D. Cobalamine

Two Vitamin whose derivatives are involved in transformation of serine to glycine are_______?

A. B6 ad B12
B. B12 and nicotinamie
C. Folic acid and B6
D. Folic acid and B12

The mineral having sparing action on Vitamin E_____?

A. Chromium
B. Iron
C. Iodine
D. Selenium

1st clinical sign of vitamin A deficiency is_______?

A. night blindness
B. bitot’s spots
C. xerostomia
D. conjunctival xeroses

Vitamin D______?

A. Absorption requires bile pigments
B. Synthesis is regulated at the reaction catalyzed by 15-hydroxylase
C. Deficiency on adults leads to rickets
D. Along with PTH, increases calcium resorption from bone

Thiamine deficiency causes decreased energy production because______?

A. It is required for the process of transamination
B. It is co-factor in oxidative reduction
C. It is co-enzyme for transketolase in pentose phosphate pathway
D. It is co-enzyme for pyruvate dehydrogenase

One molecule of B-carotene gives rise to_____?

A. 1 unit of Vitamin A
B. 2 unit of Vitamin A
C. 3 unit of Vitamin A
D. 4 unit of Vitamin A

The maximum content of vitamin E is found in______?

A. Cold liver oil
B. Fish liver oil
C. Wheat germ oil
D. Liver

Vitamin A_______?

A. Is water soluble
B. Deficiency causes impaired vision
C. Maintains normal plasma calcium levels
D. Is required for formation of clotting factors

Vitamin B12 acts as a coenzyme to which one of the following enzyme ?

A. Isocitrate dehydrogenase
B. Homocyteine methyl transferase
C. Glycogen synthase
D. G-6-P dehydrogenase

Deficiency of vitamin C causes the following except_____?

A. Painful swollen gums
B. Abnormal Collagen
C. Anaemia
D. Diarrhoea

Vit B12 is absorbed in the_______?

A. Stomach
B. Terminal ileum
C. Lower jejunum
D. Proximal ileum

Coenzyme forms are correctly matched except________?

A. Biotin – carboxylated biotin
B. Vitamin B – ATP
C. Niacin – NAD+NADP
D. Vitamin B2 – FMN+FAC

Vitamin K dependent clotting factors are_______?

A. II
B. VII
C. IX
D. X
E. All of the above

The reaction inhibited in thiamine deficiency is_______?

A. Pyruvate to acetyl CoA
B. Citrate to alpha ketoglutarate
C. Succinyl CoA to fumarate
D. None of the above

Vit-K deficiency is indicated by_____?

A. Low platelet count
B. Increased prothrombin time
C. Decreased prothrombin time
D. None of the above

Mineral present in Vit B12 is______?

A. Selenium
B. Cobalt
C. Iron
D. Calcium

Absorption of vitamin K requires normal absorption of_________?

A. Fat
B. Amino acids
C. Calcium
D. Glucose

The 3 – D’s dermatitis, diarrhoea and dementia are seen in deficiency of_______?

A. Thiamin
B. Riboflavin
C. Niacin
D. Pyridoxine

The function of vitamin A is/are related to which of the following ?

A. Retinol
B. Retinal
C. Retinoic acid
D. All of the above

Daily Vitamin A intake____?

A. 1000 I.U
B. 2000 I.U
C. 3000 I.U
D. 4000 I.U

Scurvy is the result of deficiency of____?

A. Vitamin A
B. Vitamin C
C. Vitamin B
D. Vitamin D

Deficiency of nicotinic acid results in______?

A. Beri-beri
B. Pellagra
C. Night blindness
D. Pernicious anemia

In humans and other primates as well as in guinea pigs, this vitamin cannot be synthesized because of the absence of the enzyme L-gulonolactone oxidase: the vitamin is_______?

A. Pantothenic acid
B. Nicotinic acid
C. Ascorbic acid
D. Folic acid

Deficiency of which vitamin causes glossitis dementia roughed keratotic areas on skin and gastrointestinal symptoms ?

A. Riboflavin
B. Pyridoxine
C. Niacin
D. Pantothenic acid

Rhodopsin deficiency is chiefly associated with______?

A. Vitamin D deficiency
B. Rickets
C. Vitamin A deficiency
D. Scurvy

Vitamin K______?

A. Helps in formation of prothrombin
B. Inhibition of antithrombin
C. Prevention of capillary fragility
D. Stimulation of hematopoiesis in red bone marrow

Vitamin K antagonizes______?

A. Corticosteroids
B. Thrombin formation
C. Bishydroxy coumarin
D. Production of clotting factors by liver

In vitamin A deficiency, patient complains of all of the following except___________?

A. Night blindness
B. Xerophthalmia
C. Keratosis
D. Phophoric calciuria

The vitamin that facilitates iron absorption________?

A. Folic acid
B. Ascorbic acid
C. Biotin
D. Para amino benzoic acid

Active form of vitamin D in kidney is_____?

A. 1 dihydroxy cholecalciferol
B. 25 hydroxy cholecalciferol
C. 1,25 dihydroxy cholecalciferol
D. 7 dihydroxy calciferol

Deficiency of vitamin A causes the following except______?

A. Night blindness
B. Corneal dryness
C. Bitot’s spots
D. Myopia

Fast soluble vitamins are_______?

A. A, B , D, K
B. A, D. E, K
C. A, B, E, K
D. A, C, E, K

Specific disease caused by vitamin B1 deficiency_____

A. Pellagra
B. Angular cheilitis
C. Megaloblastic anemia
D. Peripheral polyneuritis

A patient with chronic renal failure and bone pains will have deficiency of which vitamin______?

A. Vitamin A
B. Vitamin B
C. Vitamin C
D. Vitamin D

Beri-beri is caused due to the deficiency of________?

A. Thiamine
B. Pyridoxine
C. Ascorbic acid
D. Riboflavin

Which vitamin is the most indispensable during mitosis________?

A. Folic acid
B. Pantothenic acid
C. Ascorbic acid
D. Aspartic acid

Malonyl aciduria is seen in deficiency of_____?

A. Pyridoxine
B. B12
C. Folic acid
D. Riboflavin

Biological activity of tocopherols has been attributed, in part to their actions as______?

A. Antioxidant
B. Anticoagulants
C. Provitamin
D. Antidotes for selenium poisoning

Which vitamin is synthesized by intestinal bacteria ?

A. Vit B
B. Vit A
C. Vit D
D. Vit K

Of prime importance in the structure of flavoproteins is______?

A. Vit B6
B. Vit B2
C. Vit B1
D. Vit A

Vitamin also acting as hormones________?

A. Vitamin D
B. Vitamin A
C. Vitamin B1
D. Vitamin C

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