BIOCHEMISTRY MCQs


Milk is deficient in which vitamins

(A)Vitamin C (Answer)

(B) Vitamin A

(C) Vitamin B2

(D) Vitamin K


HDL is synthesized and secreted from

(A) Pancreas

(B) Liver (Answer)

(C) Kidney

(D) Muscle


Which one is the heaviest particulate component of the cell?

Nucleus(Answer)

(B) Mitochondria

(C) Cytoplasm

(D) Golgi apparatus


The most active site of protein synthesis is the

Nucleus

(B) Ribosome(Answer)

(C) Mitochondrion

(D) Cell sap


The fatty acids can be transported into and out of mitochondria through

(A) Active transport

(B) Facilitated transfer (Answer)

(C) Non-facilitated transfer

(D) None of these


Which one is the largest particulate of the cytoplasm?

(A) Lysosomes

(B) Mitochondria (Answer)

(C) Golgi apparatus

(D) Entoplasmic reticulum


Mitochondrial DNA is

(A) Circular double stranded(Answer)

(B) Circular single stranded

(C) Linear double helix

(D) None of these


The average pH of Urine is

(A) 0

(B) 6.0(Answer)

(C) 8.0

(D) 5.0


The ability of the cell membrane to act as a selective barrier depends upon

(A) The lipid composition of the membrane

(B) The pores which allows small molecules

(C) The special mediated transport systems

(D) All of these(Answer)


Carrier protein can

(A) Transport only one substance

(B) Transport more than one substance

(C) Exchange one substance to another

(D) Perform all of these functions (Answer)


 

The Golgi complex

(A) Synthesizes proteins

(B) Produces ATP

(C) Provides a pathway for transporting chemicals

(D) Forms glycoproteins (Answer)


Genetic information of nuclear DNA is transmitted to the site of protein synthesis by

(A) rRNA

(B) mRNA

(C) tRNA

(D) Polysomes(Answer)


The following substances are cell inclusions except

(A) Melanin

(B) Glycogen

(C) Lipids

(D) Centrosome(Answer)


The power house of the cell is

(A) Nucleus

(B) Cell membrane

(C) Mitochondria(Answer)

(D) Lysosomes


The digestive enzymes of cellular compounds are confined to

(A) Lysosomes (Answer)

(B) Ribosomes

(C) Peroxisomes

(D) Polysomes


The general formula of monosaccharides is

(A) CnH2nOn(Answer)

(B) C2nH2On

(C) CnH2O2n

(D) CnH2nO2n


The aldose sugar is

(A) Glycerose(Answer)

(B) Ribulose

(C) Erythrulose

(D) Dihydoxyacetone


One of the following is not double membranous structure

(A) Mitochondrion

(B) Vacuole (Answer)

(C) Chloroplast

(D) Nucleus


Modification of proteins and lipids as glycopeptides and lipo-proteins occur in

(A) Ribosomes

(B) Golgi apparatus(Answer)

(C) SER

(D) All A, B and C


Detoxification of harmful drugs is the function
(A) RER

(B) SER(Answer)

(C) Both A and B

(D) None of the above


 

Cell wall consist of

(A) One main layer

(B) Two main layers

(C) Three main layers (Answer)

(D) Four main layers


In which organelle following reaction takes place 6CO2 + 6 H2O + energy (from sunlight) ———> C6H12O6 + 6 O2

(A) Mitochondrion

(B) Peroxisome

(C) Chloroplast(Answer)

(D) Glyoxysome


SER is abundant in cells that are involved in

(A) Lipid metabolism(Answer)

(B) Protein metabolism

(C) Glucose metabolism

(D) Calcium metabolism


The door to your house is like the __________________ of a cell membrane?

(A) Phospholipid bilayer (Answer)

(B) Integral protein

(C) Recognition protein

(D) Peripheral protein


Within chloroplasts, light is captured by

(A) Grana within cisternae

(B) Thylakoids within grana(Answer)

(C) Cisternae within grana

(D) Grana within thylakoids


Which of the following correctly matches an organelle with its function?

(A) Mitochondrion . . . photosynthesis

(B) Nucleus . . . cellular respiration

(C) Ribosome . . . manufacture of lipids

(D) Central vacuole . . . storage(Answer)


The microfilaments composed of

(A) Actin protein(Answer)

(B) Gelatin protein

(C) Keratin protein

(D) Tubulin protein


Which of the following would you NOT find in a bacterial cell?

(A) DNA

(B) Cell membrane

(C) Golgi apparatus(Answer)

(D) Ribosomes


According to mosaic model by Singer and Nicholson plasma membrane is composed of

(A) Phospholipids

(B) Extrinsic proteins

(C) Intrinsic proteins

(D) All of these(Answer)


Basic solutions are also called as ____________.

(A) Proton

B) Doner

C) Alkaline(Answer)

D) Both a and b


 

Cell was for the first time discussed by __________________.

(A) Watson

b)  Schwann

C) Crick

D) none of these(Answer)


_______ to ________of the human body consists of water

(A) 40 to 60

B) 50 to 70

C) 65 to 75

D) 50 to 75(Answer)


It is recommended that teens drink ____ to ____ glasses of water each day.

(A) 2 to 4

B)  4 to 6

C) 6 to 8  (Answer)

D) 5 to 7


____________ of the earth’s surface is water.

(A) 70%

B)  65%

C) 75% (Answer)

D) 80%


Water is made up of hydrogen and oxygen molecules in the ratio ________.

(A) 1:2

B)  1:1

C) 2:1  (Answer)

D) none of these


An Acid is a substance which, when dissolved in water, releases___________.

(A) H+   (Answer)

B)  OH –

C) Alkaline

D) none of these


The hydrogen ion is called ___________.

(A) Electron

B) Bases

C) Proton(Answer)

D) Acids


A _______is a substance that releases OH-or hydroxyl ions when added to water.

(A) Acids

B) Bases (Answer)

C) Alkaline

D) Both b and c


Each pH unit represents a factor of _______ difference greater in [H+].

(A) 20 times

B) 10 times (Answer)

C) 30 times

D) none of these


___________ are used for the maintenance of pH.

(A) Buffer(Answer)

B) water

C) Hydrogen

D) Hydroxyl ions


 

If concentration of H+ is greater than 1 x 10-7 then solution is

(A) Neutral

B) basic (Answer)

C) acidic

D) aqueous


Which of the following is a non-reducing sugar?

(A) Isomaltose

(B) Maltose

(C) Lactose

(D) Trehalose (Answer)


Which of the following is a reducing sugar?

(A) Sucrose

(B) Trehalose

(C) Isomaltose(Answer)

(D) Agar


The sugar found in DNA is

(A) Xylose

(B) Ribose

(C) Deoxyribose(Answer)

(D) Ribulose


The sugar found in milk is

(A) Galactose

(B) Glucose

(C) Fructose

(D) Lactose(Answer)


Sucrose consists of

(A) Glucose + glucose

(B) Glucose + fructose(Answer)


The constituent unit of insulin is

(A) Glucose

(B) Fructose(Answer)

(C) Mannose

(D) Galactose


Starch is a

(A) Polysaccharide(Answer)

(B) Monosaccharide

(C) Disaccharide

(D) None of these


Worldwide, the most common vitamin deficiency is that of

(A) Ascorbic acid

(B) Folic acid (Answer)

(C) Vitamin A

(D) Vitamin D


Bence-Jones protein precipitates at

(A) 20°–40° C

(B) 40–-60° C (Answer)

(C) 60°–80° C

(D) 80°–100° C


 

All proteins contain the

(A) Same 20 amino acids(Answer)

(B) Different amino acids

(C) 300 Amino acids occurring in nature

(D) Only a few amino acids


The optically inactive amino acid is

(A) Glycine

(Answer)

(B) Serine

(C) Threonine

(D) Valine


The functions of plasma albumin are

(A) Osmosis(Answer)

(B) Transport

(C) Immunity

(D) both (A )and (B)


An essential amino acid in man is

(A) Aspartate

(B) Tyrosine

(C) Methionine (Answer)

(D) Serine


Non essential amino acids

(A) Are not components of tissue proteins

(B) May be synthesized in the body from essential amino acids (Answer)

(C) Have no role in the metabolism

(D) May be synthesized in the body in diseased states


Which one of the following is semiessential amino acid for humans?

(A) Valine

(B) Arginine(Answer)

(C) Lysine

(D) Tyrosine


An example of polar amino acid is

(A) Alanine

(B) Leucine

(C) Arginine(Answer)

(D) Valine


A ketogenic amino acid is

(A) Valine

(B) Cysteine

(C) Leucine(Answer)

(D) Threonine


After releasing O2 at the tissues, hemoglobin transports

(A) CO2 and protons to the lungs (Answer)

(B) O2 to the lungs

(C) CO2 and protons to the tissue

(D) Nutrients


The protein present in hair is

(A) Keratin(Answer)

(B) Elastin

(C) Myosin

(D) Tropocollagen


 

Net protein utilisation of egg protein is

(A) 75%

(B) 80%

(C) 91%(Answer)

(D) 72%


Net protein utilization of milk protein is

(A) 75%(Answer)

(B) 80%

(C) 86%

(D) 91%


Pulses are rich in

(A) Lysine (Answer)

(B) Methionine

(C) Tryptophan

(D) Phenylalanine


Milk is deficient in

(A) Vitamin B1

(B) Vitamin B2

(C) Sodium(Answer)

(D) Potassium


An example of a hydroxy fatty acid is

(A) Ricinoleic acid (Answer)

(B) Crotonic acid

(C) Butyric acid

(D) Oleic acid


An example of a saturated fatty acid is

(A) Palmitic acid (Answer)

(B) Oleic acid

(C) Linoleic acid

(D) Erucic acid


The number of double bonds in arachidonic acid is

(A) 1

(B) 2

(C) 4(Answer)

(D) 6


Dietary fats after absorption appear in the circulation as

(A) HDL

(B) VLDL

(C) LDL

(D) Chylomicron(Answer)


The deficiency of both energy and protein causes

(A) Marasmus(Answer)

(B) Kwashiorkar

(C) Diabetes

(D) Beri-beri


Kwashiorkar is characterized by

(A) Night blindness

(B) Edema(Answer)

(C) Easy fracturability

(D) Xerophthalmia


 

1. Glucosomes helps in
a) Fat synthesis
b) Glucose synthesis✅
c) Starch
d) Carbohydrates


2. Myofibril helps in
a) Muscular contraction✅
b) Ligamentus contraction
c) Both a & b
d) None


3. Ribosomes helps in
a) Translation of RNA into protein✅
b) Translation of DNA into protein
c) Conversion of fats into acids
d) None


4. Peroxisomes
a) Breakdown of hydrogen peroxide✅
b) Formation of hydrogen peroxide
c) Breakdown of hydrogen dioxide
d) Formation of hydrogen dioxide


5. Glyoxysomes helps in
a) Conversion of sugar into fats
b) Conversion of fats into sugar✅
c) Conversion of acids into bases
d) Conversion of bases into acids


6. Carboxysomes helps in
a) Carbon fixation✅
b) Oxygen fixation
c) Carbon monoxide fixation
d) None


7. Plasmid is
a) Circular RNA
b) Spring shape DNA
c) Circular DNA✅
d) Both b & c


8. Types of protein
a) Fibrous
b) Globular
c) Membrane
d) All of them✅


9. Structure types of membrane proteins
a) Beta barrels
b) Helix bundles
c) Both a & b✅
d) none


10. examples of environmental stimuli
a) photon hitting cells in retina of eye
b) odorants binding to odorant receptors in nose
c) both a & b✅
d) none


 

11. types of second messenger are
a) hydrophilic
b) hydrophobic
c) gases
d) all of these✅
12. examples of extra cellular receptors
a) G protein coupled receptors
b) Receptor tyrosine kinase
c) Integrin
d) All✅


13. Types of intra cellular receptors
a) Nuclear receptors
b) Cytoplasmic receptors
c) Both a & b✅
d) Mitochondrial receptors


14. G protein coupled receptors have
a) Protein+ G protein (G alpha, G beta ,G gamma)✅
b) G protein
c) G protein (alpha , beta)
d) G protein (alpha, beta, gamma)


15. Receptor tyrosin kinase is
a) Transmembrane protein
b) Transmembrane protein & have 2 domains✅
c) Transmembrane and have 1 domain
d) 2 domains only


16. Weak acid and bases
a) Only partially ionizes✅
b) Completely ionizes
c) May or may not
d) All


17. PH is
a) Potency of hydrogen ion concentration✅
b) Potency of OH ion concentration
c) Both
d) None


18. PH + POH=
a) 14✅
b) 15
c) 20
d) 21


19. Acid dissociation constant
a) Ka ✅
b) Kw
c) Kc
d) Pk


20. Kw is
a) Equilibrium constant of water✅
b) Acid dissociation constant
c) Base dissociation constant
d) None


 

21. PH+POH=14
a) 9+5=14
b) 8+6=14
c) 7+7=14✅
d) 10+4=14


22. Buffers
a) resist changes in pH from the addition of acid or base
b) resist changes in pH from the addition of acid or base
c) resist changes in pH from the addition of acid or base
d) all✅


23. components of buffer are
a) acid–base conjugate pairs
b) can be a weak acid and a salt of its conjugate base
c) can also be a weak base and a salt of its conjugate acid
d) all✅


24. Does each of the following combinations produce a buffer solution or not
a) . HCl and KCl
b) H2CO3 and NaHCO3✅
c) H3PO4 and NaCl
d) HC2H3O2 and KC2H3O2
Biochemistry


1. What are short polypeptides called?
A. Primary structures
B. Secondary structures
C. Polypeptides
D. Oligopeptides✅


2. What is comprised of alpha-helices or parallel or antiparallel beta-pleated sheets?
A. Primary structures
B. Secondary structures✅
C. Both A and B
D. None of the above


3. At what amino acids can beta-turns occur?
A. Glycine and alanine
B. Glycine and proline✅
C. Glutamate and proline
D. Glutamate and alanine

4. Where can disulfide covalent linkages occur between adjacent alpha-helices?
A. In keratin
B. In the major protein of hair
C. In nails
D. All of the above✅


5. Which of the following is a incomplete dietary protein found in connective tissues?
A. Collagen✅
B. Keratin
C. RNase A
D. All of the above


6. What is the cause of scurvy?
A. Not being exposed to enough sunlight
B. Misfolding protiens
C. Defective collagen✅ formation
D. All of the above


7. Fats and oils are also known as _______?
A. Polypeptides
B. Polymers
C. Tripeptides
D. Triglycerides✅
E. Trisaccharides


8. What is the relationship between glucose, mannose and galactose?
A. They are isomers
B. They are epimers✅
C. They are ketoses
D. No relationship exists


9. What is used to identify reducing sugars and in the past was used to test for diabetes mellitus?
A. Benedict’s test✅
B. N-glycosylation
C. O-glycosylation
D. None of the above


10. What best describes amylose?
A. Unbranched linear polymer with alpha 1-4 glycosidic linkages✅
B. Unbranched linear polymer with beta 1-4 glycosidic linkages
C. Highly branched, branched sites contain alpha 1-6 glycosidic linkages
D. Highly branched, branched sites contain beta 1-6 glycosidic linkages


 

11. What best describes amylopectin?
A. Unbranched linear polymer with alpha 1-4 glycosidic linkages
B. Unbranched linear polymer with beta 1-4 glycosidic linkages
C. Highly branched, branched sites contain alpha 1-6 glycosidic linkages✅
D. Highly branched, branched sites contain beta 1-6 glycosidic linkages


12. Where is glycogen stored?
A. In the kidney and liver
B. In the stomach and kidney
C. In the muscle and liver✅
D. In the muscle and stomach


13. In the conversion of glucose and oxygen to carbon dioxide and water, which molecule is oxidized?
A. Oxygen
B. Carbon dioxide
C. Glucose✅
D. Water


14. NAD+ is a __________, its reduced form is _____________.
A. Electron carrier, NADPH
B. Electron carrier, NADH✅
C. Reducing agent, NAD
D. Transport protein, NADH


15. What is the role of oxygen in cellular respiration?
A. It is reduced in glycolysis as glucose is oxidized
B. It provides electrons to the ETC
C. It provides the activation energy needed for oxidation to occur
D. It is the final electron acceptor for the ETC✅
E. It combines with the carbon removed during the citric acid cycle to form carbon dioxide


16. How many molecules of carbon dioxide are generated for each molecule of acetyl CoA introduced into the citric acid cycle?
A. 1
B. 2✅
C. 3
D. 4


17. Which of the following reactions is incorrectly paired with its location?
A. ATP synthysis-inner membrane of the mitochondrion, matrix, and cytosol
B. Fermentation – cell cytosol
C. Glycolysis – cell cytosol
D. Substrate level phosphorylation – cytosol & matrix
E. Citric acid cycle – cristae of mitochondrion✅


18. Why is glycolysis considered one of the first metabolic pathways to have evolved?
A. It relies on fermentation, which is characteristic of archaea & bacteria
B. It is found only in prokaryotes, whereas eukaryotes use their mitochondria to produce ATP
C. It produces much less ATP than does the electron transport chain & chemiosmosis
D. It relies totally on enzymes that are produced by free ribosomes, and bacteria have only free ribosomes and no bound ribosomes
E. It is nearly universal, is located in the cytosol, and does not involve oxygen✅


19. Cyanide is a poison that blocks the passage of electrons along the ETC. Which of the following is a metabolic effect of this poison?
A. No proton gradient would be produced, and ATP synthesis would cease✅
B. NADH supplies would be exhausted, and ATP synthesis would cease
C. Alcohol would build up in the cells
D. Electrons are passed directly to oxygen, causing cells to explode
E. The pH of the intermembrane space becomes much lower than normal


20. Account for the net production of ATP at each step of cell respiration for one molecule of glucose.
A. Glycolysis=2, citric acid cycle=2, oxidative phosphorylation=32✅
B. Glycolysis=4, citric acid cycle=2, oxidative phosphorylation=32
C. Glycolysis=2, citric acid cycle=1, oxidative phosphorylation=32
D. Glycolysis=2, citric acid cycle=2, oxidative phosphorylation=36


 

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