R4RIN – MCQs, Mock Tests | Biochemistry Biochemistry MCQS PAPER SET 6

Which of the following can be diagnosed by amniocentesis?

1. Down's syndrome
2. Cystic Fibrosis
3. Sickle cell anemia
4. All of these

✅ Correct Answer: 4

Fructose is metabolized by

1. fructose 1-phosphate pathway
2. fructose 6-phosphate pathway
3. glyceraldehyde 3-phosphate pathway
4. both (a) and (b)

✅ Correct Answer: 4

A common way that cells capture the energy released during the breakdown of large molecules is to add electrons to smaller, specialized molecules that can accept them. This process of electron acceptance is otherwise known as

1. biosynthesis
2. metabolism
3. reduction
4. catalysis

✅ Correct Answer: 3

Humans are unable to digest

1. starch
2. complex carbohydrates
3. denatured proteins
4. cellulose

✅ Correct Answer: 4

How many ATP equivalents per mole of glucose input are required for gluconeogenesis?

1. 2
2. 6
3. 8
4. 4

✅ Correct Answer: 2

Which of the following compounds is responsible for coordinated regulation of glucose and glycogen metabolism?

1. NAD+
2. Fructose 2,6 bisphosphate
3. Acetyl-CoA
4. Fructose 1,6 bisphosphate

✅ Correct Answer: 2

Gluconeogenesis requires a higher amount of ATP equivalents as compared to that produced by glycolysis because

1. gluconeogenesis releases energy as heat
2. glycolysis releases energy as heat
3. glycolysis occurs in the mitochondria while gluconeogenesis occurs in the cytosol
4. all of the above

✅ Correct Answer: 2

Which of the following is carried out when cAMP functions as a second messenger?

1. Acts second in importance to AMP
2. Activates all cytosolic protein kinases
3. Activates the cAMP-dependent protein kinase
4. Acts outside the cell to influence cellular processes

✅ Correct Answer: 3

The production or break down of __________ is often coupled with the metabolic reactions of biosynthesis and catabolism.

1. aspirin
2. DNA
3. ATP
4. CO2

✅ Correct Answer: 3

The cells dependent solely on glucose as an energy source are

1. muscle cells
2. brain cells
3. kidney cells
4. liver cells

✅ Correct Answer: 2

The main site for gluconeogenesis is

1. kidney
2. liver
3. brain
4. muscle

✅ Correct Answer: 2

Which of the following statements about the energy needs of cells is false?

1. Without a continuous input of energy, cell disorder will increase
2. The laws of thermodynamics force cells to acquire energy
3. Many cellular reactions have an associated activation energy
4. The most usable energy for cells comes from the rapid combustion of glucos

✅ Correct Answer: 4

In lysozyme catalysis, which of the following does not contribute?

1. The abnormally high pKa of Glu35
2. The strained conformation of the D sugar
3. Formation of a covalent intermediate at Asp52
4. Formation of a covalent intermediate at Ser195

✅ Correct Answer: 4

Cellulose fibers resemble with the protein structure in the form of

1. β-sheets
2. α-helices
3. β-turns
4. None of these

✅ Correct Answer: 1

During vigorous exercise, pyruvate produced by glycolysis is converted to

1. acetate
2. lactate
3. monosodium phosphate
4. pyruvic acid

✅ Correct Answer: 2

Glucagon and epinephrine

1. inhibits gluconeogenesis and stimulates glycolysis
2. stimulates gluconeogenesis and glycolysis
3. stimulates gluconeogenesis and inhibits glycolysis
4. inhibits gluconeogenesis and glycolysis

✅ Correct Answer: 3

The NAG6 substrate is hydrolyzed by human lysozyme to form

1. 6 glucosamines + 6 acetic acids
2. NAG4 + NAG2
3. NAG3 + NAG3
4. NAG3

✅ Correct Answer: 2

Gluconeogenesis uses

1. 3 ATPs and 2 GTPs per glucose
2. 2 ATPs and 1 GTPs per glucose
3. 3 ATPs and 3 GTPs per glucose
4. 4 ATPs and 2 GTPs per glucose

✅ Correct Answer: 4

Saliva contains all of the following except

1. hormones
2. amylase
3. bacteria-killing enzymes
4. antibodies

✅ Correct Answer: 1

The conversion of pyruvate to oxaloacetate

1. requires biotin
2. involves the fixation of carbon dioxide
3. occurs in the mitochondria
4. all of the above

✅ Correct Answer: 1

Gluconeogenesis is the

1. formation of glycogen
2. breakdown of glucose to pyruvate
3. breakdown of glycogen to glucose
4. synthesis of glucose from non-carbohydrate precursors

✅ Correct Answer: 4

Hydrolysis of lactose yields

1. galactose and fructose
2. galactose and glucose
3. glucose and fructose
4. fructose and galactose

✅ Correct Answer: 2

Two major products of pentose phosphate pathway are

1. nicotinamide adenine dinucleotide and ribose 5-phosphate
2. flavine adenine dinuclueotide and glucose 5-phosphate
3. FAD and CoA
4. NADPH and NAD

✅ Correct Answer: 1

A catabolic intermediate which stimulates phosphofructokinase would stimulate

1. gluconeogenesis
2. glycolysis
3. glycogen synthesis
4. none of these

✅ Correct Answer: 2

Pyruvate is initially converted to which of the following in the gluconeogenesis?

1. Glycerol
2. Phosphoenol pyruvate
3. Oxaloacetate
4. Acetyl CoA

✅ Correct Answer: 3

Boat and chair conformations are found

1. in pyranose sugars
2. in any sugar without axial -OH groups
3. in any sugar without equatorial -OH groups
4. only in D-glucopyranose

✅ Correct Answer: 1

The conversion of pyruvate to lactate is catalysed by

1. pyruvate carboxylase
2. lactate dehydrogenase
3. pyruvate dismutase
4. pyruvate decarboxylase

✅ Correct Answer: 2

Which of the following can act as precursors for gluconeogenesis?

1. Lactate
2. Glycerol
3. Alanine
4. All of these

✅ Correct Answer: 4

a-amylose is similar to

1. β-sheets
2. β-turned coils
3. α-helices
4. the hydrophobic core

✅ Correct Answer: 3

Storage polysaccharide made by animals is

1. amylopectin
2. glycogen
3. cellulose
4. collagen

✅ Correct Answer: 2

The glycosidic bond

1. in maltose is not hydrolyzed in lactose intolerant humans
2. in sucrose is hydrolyzed by bees
3. joins glucose and fructose to form sucrose
4. both b and c

✅ Correct Answer: 4

The sugar which forms major component of nucleic acids is

1. ribose
2. galactose
3. mannose
4. maltose

✅ Correct Answer: 1

Under aerobic condition pyruvate is converted by pyruvate dehydrogenase to

1. phosphoenol pyruvate
2. acetyl CoA
3. lactate
4. glyceraldehyde 3 phosphate

✅ Correct Answer: 2

Which of the following is not a disaccharide?

1. Amylose
2. Cellobiose
3. Lactose
4. None of these

✅ Correct Answer: 1

Hexokinase activity in glycolysis is inhibited by

1. glucose 6- phosphate
2. fructose 6-phosphate
3. fructose 1,6 biphosphate
4. phosphofructokinase

✅ Correct Answer: 1

The ultimate source of energy that sustains living systems is

1. glucose
2. oxygen
3. sunlight
4. carbon dioxide

✅ Correct Answer: 3

Citric acid accumulation would

1. stimulate phosphofructokinase activity
2. stimulate fructose 1,6 diphosphatase activity
3. inhibit phosphofructokinase activity
4. both (b) and (c)

✅ Correct Answer: 4

Which of the following is not involved in the biosynthesis of DNA?

1. Energy from ATP
2. Mononucleotides
3. Carbonic anhydrase
4. Enzymes

✅ Correct Answer: 3

Which of the following would be considered a part of metabolism?

1. Biosynthetic pathways that build DNA
2. Catabolic pathways that break down complex carbohydrates
3. The capture of light energy for use in making glucose
4. All of the above

✅ Correct Answer: 4

Insulin

1. stimulates gluconeogenesis and glycolysis
2. stimulates gluconeogenesis and inhibits glycolysis
3. inhibits gluconeogenesis and glycolysis
4. inhibits gluconeogenesis and stimulates glycolysis

✅ Correct Answer: 1

What is present in the stomach to prevent self-digestion?

1. Mucus
2. acid
3. Enzymes
4. hormones

✅ Correct Answer: 1

The key enzyme in the regulation of fatty acid synthesis is

1. acetyl CoA carboxylase
2. AMP activated proteinkinase
3. protein phosphatase
4. none of these

✅ Correct Answer: 1

In the intestine, the dietary fats are hydrolysed by

1. triacylglycerol lipase
2. adenylate cyclase
3. pancreatic lipase
4. protein kinase

✅ Correct Answer: 3

HDLs are synthesized in

1. blood
2. liver
3. intestine
4. pancreas

✅ Correct Answer: 3

Triacylglycerols are

1. soluble in water
2. insoluble in water
3. soluble in water at elevated temperature
4. partially soluble in water

✅ Correct Answer: 2

Animals cannot convert fatty acids into glucose because

1. acetyl CoA can not be converted to pyruvate
2. absence of malate synthase
3. absence of dehydrogenase
4. absence of a-ketoglutarate dehydrogenase

✅ Correct Answer: 1

What is the major protein constituent of high-density lipoprotein (HDL)?

1. Apolipoprotein A-l
2. Apolipoprotein C-l
3. Apolipoprotein E
4. None of these

✅ Correct Answer: 1

Phospholipid contains

1. hydrophilic heads and hydrophobic tails
2. long water-soluble carbon chains
3. positively charged functional groups
4. both (b) and ( c)

✅ Correct Answer: 1

Micelles of fatty acids in water are organized such that the __________ faces the solvent and the __________ are directed toward the interior

1. carboxylic acid groups, hydrocarbon chains heads
2. hydrophilic heads, hydrophobic tails
3. hydrocarbon chains, carboxylic acid groups
4. both (a) and (b)

✅ Correct Answer: 4

Cholesterolemia means

1. lack of functional LDL receptors
2. lack of functional HDL receptor
3. high sensitivity to fatty food intake
4. none of the above

✅ Correct Answer: 1

Fatty acids break down of eukaryotes occurs in

1. mitochondrial matrix
2. cell membrane
3. cytosol
4. endoplasmic reticulum

✅ Correct Answer: 1

VLDLs are synthesized in

1. blood
2. liver
3. intestine
4. pancreas

✅ Correct Answer: 2

Chylomicrons are synthesized in

1. blood
2. liver
3. intestine
4. pancreas

✅ Correct Answer: 3

How many types of lipoproteins are there?

1. 2
2. 6
3. 8
4. 5

✅ Correct Answer: 4

Fatty acid synthesis takes place in

1. mitochondria
2. cell membrane
3. cytosol
4. endoplasmic reticulum

✅ Correct Answer: 3

Cholestrol is the precursor of

1. steroid hormones
2. vitamin A
3. bile salts
4. both (a) and c

✅ Correct Answer: 4

Atherosclerosis can cause blood

1. thinning
2. clotting
3. thickening
4. none of these

✅ Correct Answer: 2

Palmitate has 16 carbon atoms with

1. 2 double bonds
2. 3 double bonds
3. One double bond
4. None of these

✅ Correct Answer: 4

How many ATPs are formed during complete oxidation of palmitate?

1. 35
2. 96
3. 129
4. 131

✅ Correct Answer: 3

The lowest energy value lipid for human nutrition is

1. olive oil
2. olestra
3. margarine
4. cardiolipih

✅ Correct Answer: 2

How many classes of steroid hormones are there?

1. 2
2. 9
3. 4
4. 5

✅ Correct Answer: 4

The number of water molecules consumed by the formation of phosphatidyl serine are

1. 0
2. 1
3. 2
4. 4

✅ Correct Answer: 1

Synthesis of fatty acid takes place when

1. fatty acid are plentiful
2. carbohydrate is plentiful
3. carbohydrate and energy are plentiful
4. none of these

✅ Correct Answer: 3

Which of the following is called milk ejection hormone?

1. Prolactin
2. Vasopressin
3. Oxytocin
4. All of these

✅ Correct Answer: 3

How many molecules of ATPs are synthesized per NADH oxidation?

1. 2
2. 1
3. 3
4. 4

✅ Correct Answer: 3

Why is the TCA cycle the central pathway of metabolism of the cell?

1. It occurs in the center of the cell
2. Its intermediates are commonly used by other metabolic reactions
3. All other metabolic pathways depend upon it
4. None of the above

✅ Correct Answer: 2

In what form does the product of glycolysis enter the TCA cycle?

1. AcetylCoA
2. Pyruvate
3. NADH
4. Glucose

✅ Correct Answer: 1

Malate-asparatate shuttle operates in

1. lungs and liver
2. heart and liver
3. pancreas and liver
4. none of these

✅ Correct Answer: 2

Oxidation of a molecule involves

1. gain of electron
2. loss of electron
3. gain of proton
4. loss of proton

✅ Correct Answer: 2

During cellular respiration, most of the ATP made, is generated by

1. oxidative phosphorylation
2. photophosphorylation
3. glycolysis
4. substrate-level phosphorylation

✅ Correct Answer: 1