COMPILED Flashcards
1
Q
It is the science concerned with the chemical basis of life:
A. Biology
B. Pharmacology
C. Biochemistry
D. Physics
E. Geology
A
C. Biochemistry
2
Q
Organelle – free cell sap where metabolic pathways such as glycolysis, glycogenesis, and fatty acid synthesis is commonly seen on:
A. Cytoplasm
B. Cytosol
C. Mitochondrion
D. Endoplasmic reticulum
E. Nucleus
A
B. Cytosol
3
Q
Which of the following cellular structures is unique in eukaryotes?
A. Plasma membrane
B. Internal cellular membrane
C. Ribosomes
D. Endoplasmic Reticulum
E. Golgi apparatus
A
B. Internal cellular membrane
4
Q
It is the organelle which serves as the site of the electron transport chain:
A. Mitochondria
B. Ribosome
C. Nucleus
D. Lyososome
E. Golgi body
A
A. Mitochondria
5
Q
Site of lipid synthesis in cells:
A. Golgi apparatus
B. Lysosome
C. Nucleolus
D. Smooth Endoplasmic reticulum
E. Nucleus
A
D. Smooth Endoplasmic reticulum
6
Q
This organelle is referred to as “suicide bag” due to the presence of enzymes:
A. Lysosome
B. Peroxisome
C. Chromatin
D. Mitochondria
E. Endoplasmic reticulum
A
A. Lysosome
7
Q
The ________ is the most important measure used to distinguish ribosomes:
A. subunit
B. molecular weight
C. svedberg
D. seconds
E. Both A and B
A
C. svedberg
8
Q
All of the following are present only on plant cell, except:
A. Cell wall
B. Plastids
C. Mitochondria
D. Vacuoles
E. C and D
A
E. C and D
9
Q
Bacterial cell wall : Peptidoglycan; Plant cell wall: ________
A. Cellulose
B. Nucleic acid
C. Starch
D. Glycogen
E. Plasmid
A
A. Cellulose
10
Q
Which statement is/are correct?
A. Endoplasmic reticulum (ER) is a system of fluid – filled cisterns
B. Smooth ER is responsible for protein synthesis
C. Rough ER is the site for protein synthesis
D. Statement B and C are correct
E. All of these
A
C. Rough ER is the site for protein synthesis
11
Q
____________ are small, extrachromosomal circular DNA molecules present in eukaryotes:
A. Nucleoli
B. Genes
C. Chromosomes
D. Plasmids
E. Histones
A
C. Chromosomes
12
Q
An organelle is the portion of a cell enclosed by a membrane. Based on this, which of the following is not strictly an organelle?
A. Mitochondria
B. Lysosome
C. Ribosome
D. Endoplasmic reticulum
A
C. Ribosome
13
Q
The following are phospholipids, except:
A. Plasmalogen
B. Lecithin
C. Cephalin
D. Choline
A
D. Choline
14
Q
The fluid-mosaic model for membrane structure proposes that:
A. the outer and inner faces of the membrane are identical
B. peripheral proteins are situated only on the outer face of the plasma membrane
C. integral proteins are associated with the hydrophobic phase of the bilayer
D. polar and non – polar ends of membrane phospholipids are within the hydrophobic phase of the bilayer
A
C. integral proteins are associated with the hydrophobic phase of the bilayer
15
Q
Mediated (facilitated) diffusion of substances across cell membranes differs from simple diffusion in that mediated diffusion:
A. requires ATP
B. requires another solute
C. is a one-directional process
D. exhibits saturation kinetics
A
D. exhibits saturation kinetics
16
Q
Gangliosides are glycolipids found on various cell surfaces. In addition to sphinogosine, their unit composition contains another component called ____.
A. Uronic acid
B. Plasmalogen
C. Triglyceride
D. N – acetylmuramic acid
E. N – acetylneuraminic acid
A
E. N – acetylneuraminic acid
17
Q
Neutral fats contain mixtures of one or more fatty acids esterified with:
A. Sterol
B. Glycerol
C. Sphinogosine
D. Alcohols of high molecular weight
E. Lecithin
A
B. Glycerol
18
Q
Phosphatidylcholine is also known as:
A. Lecithin
B. Cephalin
C. Plasmalogen
D. Cardiolipin
E. Sphingomyeline
A
A. Lecithin
19
Q
General formula of carbohydrates:
A. C-H2O
B. CH3CH2OH
C. CnH2nO2
D. (C-H2O)n
A
D. (C-H2O)n
20
Q
The following sugars are aldohexoses, except:
A. Fructose
B. Glucose
C. Galactose
D. Mannose
A
A. Fructose
21
Q
It is a general test for carbohydrates that contains alpha napthol and sulfuric acid:
A. Benedict’s
B. Molisch
C. Fehling’s
D. Tollen’s
A
B. Molisch
22
Q
Lactose can be differentiated from fructose by:
A. Mucic acid Test
B. Barfoed’s Test
C. Fehling’s Test
D. Iodine Test
A
B. Barfoed’s Test
23
Q
Alkaline bismuth reagent is used to detect the presence of:
A. Polysaccharide
B. Disaccharide
C. Monosaccharide
D. All of these
A
C. Monosaccharide
24
Q
Osazone test in also known as:
A. Nylander’s test
B. Trummer’s Test
C. Kowarsky Test
D. Folin’s Test
A
C. Kowarsky Test
25
The main carbohydrate of the blood is:
A. D-fructose
B. D-glucose
C. Mannitol
D. Sorbitol
B. D-glucose
26
The end product of the hydrolysis of glycogen is:
A. Galactose
B. Fructose
C. Glucose
D. Arabinose
C. Glucose
27
Starches are partially digested in the mouth by:
A. Protease
B. Starchase
C. Ptyalin
D. Gastrin
C. Ptyalin
28
A normal value of glucose in the blood:
A. 100 – 200 mg%
B. 80 – 120 mg%
C. 50 – 75 mg%
D. 200 – 300 mg%
B. 80 – 120 mg%
29
Which sugar will not give a red precipitate with cupric oxide when heated with Benedict’s solution?
A. Glucose
B. Sucrose
C. Maltose
D. Fructose
B. Sucrose
30
Which of the following sugar is sweetest?
A. Glucose
B. Fructose
C. Sucrose
D. Galactose
B. Fructose
31
Which of the following statement is incorrect?
A. Ribose is an aldopentose
B. Maltose is a ketohexose
C. Galactose is an aldohexose
D. Glucose is an aldohexose
B. Maltose is a ketohexose
32
Concentrated dehydrating acids change monosaccharides to:
A. Simple sugars
B. Saccharic acids
C. Furfurals
D. Uronic acid
C. Furfurals
33
Lactose intolerance is due to:
A. Inability of some people to digest the alpha glycosidic bond
B. Inability of some people to digest the beta glycosidic bond
C. Alcohol production
D. Production of non – reducing equivalents
B. Inability of some people to digest the beta glycosidic bond
34
Oligosaccharides that cannot be absorbed by the small intestine and are often metabolized by bacteria in the large intestine to form unwanted gaseous byproducts:
A. Amylose and amylopectin
B. Raffinose and Stachyose
C. Cellulose and inulin
D. Dextrin and invert sugars
B. Raffinose and Stachyose
35
Which of the following is TRUE?
A. Fructose is an aldose while glucose is a ketose
B. Fructose in solution is in pyranose form
C. Fructose and Glucose are hexoses
D. Glucose in solution is levorotatory
C. Fructose and Glucose are hexoses
36
________ are formed by the condensation between the hydroxyl group of the anomeric carbon of monosaccharide and a second compound that may not be another monosaccharide.
A. Amino sugars
B. Deoxysugars
C. Mucopolysaccharides
D. Glycosides
E. Disaccharides
D. Glycosides
37
Amylose is:
A. Branched chains composed of 24-30 glucose residues
B. Non-branching helical structure
C. A constituent of chitin
D. Non digestible non starch polysaccharide
B. Non-branching helical structure
38
Branching frequency of glycogen’s structure:
A. Every 4-6 glucose units
B. Every 6-10 glucose units
C. Every 12-14 glucose units
D. Every 2-6 glucose units
E. Every 25-30 glucose units
C. Every 12-14 glucose units
39
When the C1 of monosaccharides become chiral, it is now known as/an:
A. Epimeric carbon
B. Enantiomeric carbon
C. Assymetric carbon
D. Anomeric carbon
E. Acetal carbon
D. Anomeric carbon
40
It is the glycosidic linkage that binds 2 molecules of glucose to form maltose:
A. β – 1,2
B. β – 1,4
C. α – 1,4
D. α – 1,2
E. α – 4,1
C. α – 1,4
41
Glucose and Mannose are epimers at:
A. Carbon 2
B. Carbon 3
C. Carbon 4
D. Carbon 5
A. Carbon 2
42
Alpha – naphthol reaction is also known as:
A. Molisch’s Test
B. Ninhydrin Test
C. Phenylhydrazine Test
D. Fehling’s Test
E. Biuret Test
A. Molisch’s Test
43
D- threose and L-threose are examples of:
A. Anomers
B. Enantiomers
C. Diastereomers
D. Conformational isomer
E. Nucleic acids
B. Enantiomers
44
Genetic defect characterized by mental retardation and cataract, since the unmetabolized sugar is toxic to the lens of the eyes:
A. Galactosemia
B. Pentosuria
C. Fructosemia
D. Fructosuria
A. Galactosemia
45
Oligosaccharides that cannot be absorbed by the small intestine and are often metabolized by bacteria in the large intestine to form unwanted gaseous byproducts.
A. Amylose and amylopectin
B. Raffinose and Stachyose
C. Cellulose and inulin
D. Dextrin and invert sugars
B. Raffinose and Stachyose
46
Cellulose is a polysaccharide found in:
A. Plants
B. Soil
C. Mammalian tissues
D. Animal fat
A. Plants
47
Hydrolysis of sucrose by the enzyme sucrase yields:
A. Glucose only
B. Glucose and maltose
C. Glucose and fructose
D. Glucose and galactose
E. Fructose and maltose
C. Glucose and fructose
48
The arrangement of sugars into D- and L-configurations is based upon their resemblance to D- and L-:
A. Glycine
B. Glucose
C. Fructose
D. Glyceraldehyde
D. Glyceraldehyde
49
Some carbohydrates convert Cu2+ ions to Cu+ ions. This property is related to their ability to act as:
A. a reducing agent
B. an oxidizing agent
C. both a reducing agent and an oxidizing agent
D. neither a reducing agent nor an oxidizing agent
A. a reducing agent
50
What linkages occur in glycogen at branch points between glucose units?
A. Alpha-1,4
B. Alpha-1,6
C. Beta-1,3
D. Beta-1,4
E. Beta-1,6
B. Alpha-1,6
51
How many anomeric carbons are present in a fructose molecule?
A. 0
B. 1
C. 2
D. 5
E. 6
B. 1
52
Each of the following is a glycosaminoglycan, except:
A. Chondroitin sulfate
B. Dermatan sulfate
C. Hyaluronic acid
D. Heparan sulfate
E. Keratin
E. Keratin
53
Which of the following molecule features contributes to the water-binding properties of proteoglycans?
A. The carboxyl groups acting as buffers
B. Central hyaluronate (a helix) trapping water within
C. The space between the core proteins and the hyaluronate being highly charged.
D. The large number of alcohol groups on the polysaccharide chaining H-bond to water.
E. The large number of serine and theronine residues in the core protein offering H-bonding sites.
D. The large number of alcohol groups on the polysaccharide chaining H-bond to water.
54
Amino sugar found in chondroitin:
A. N – acetylfructosamine
B. N – acetylglucosamine
C. N – acetylgalactosamine
D. N – acetylmuraminic acid
E. N – acetylmannosamine
C. N – acetylgalactosamine
55
The carbohydrate in highest concentration in resting muscle is:
A. Glucose
B. Lactose
C. Sucrose
D. Glycogen
E. Inositol
D. Glycogen
56
Which of the following type of glycogen storage disease is correctly matched?
I. Type I: von Gierk’s
II. Type VII: Tarui’s disease
III. Type II: Pompe’s disease
IV. Type III: Cori’s diease
A. I and II only
B. I, II, III and IV
C. II, III and IV only
D. I and III only
B. I, II, III and IV
57
Lactose is chemically known as:
A. Glucopyranosyl 1->4 glucopyranose
B. Galactopyranosyl 1->4 glucopyranose
C. Glucopyranosyl 1->2 fructofuranoside
D. Galactopyranosyl 1->4 fructofuranose
B. Galactopyranosyl 1->4 glucopyranose
58
The reserve carbohydrates of plants is/are:
A. Cellulose
B. Glycogen
C. Starch
D. A and C
E. All are storage form of carbohydrates
C. Starch
59
These are substances grouped together on the basis of their insolubility in water and solubility in most organic solvents:
A. Nucleic acids
B. Carbohydrates
C. Lipids
D. Proteins
C. Lipids
60
A condition known as atherosclerosis results as an accumulation in the blood vessels of:
A. Calcium
B. Cholesterol
C. Pathogens
D. Ketones
B. Cholesterol
61
As the number of grams of iodine chemically react with 100g of fats:
A. Saponification Number
B. Iodine Number
C. Ester Value
D. Acid Value
E. Both A and B
B. Iodine Number
62
The clinical test for the determination of cholesterol:
A. Liebermann – Burchard
B. Salkowski
C. A and B
D. None of these
C. A and B
63
It is defined as ester of fatty acids with glycerol:
A. Waxes
B. Fats
C. Simple lipids
D. Glycolipids
B. Fats
64
The metallic salt of a high fatty acid:
A. Soap
B. Trypsin
C. Chymotrypsin
D. Carboxypeptidase
A. Soap
65
This eicosanoid is a pro-inflammatory agent and play a part in asthma:
A. Prostaglandin
B. Prostacyclin
C. Thromboxane
D. Leukotrienes
D. Leukotrienes
66
Rancidity of fats maybe due to:
A. Oxidation
B. Hydrogenation
C. Saponification
D. Condensation
A. Oxidation
67
Cholesterol is a major constituent of:
A. Plasma membrane
B. Plasma lipoprotein
C. Plant tissues
D. A and B
E. All of these
D. A and B
68
Which of the following is considered to be the good cholesterol?
A. VLDL
B. LDL
C. IDL
D. HDL
E. TAGs
D. HDL
69
The chemical precursor to all prostaglandins is:
A. Arachidonic acid
B. Cholesterol
C. Leukotriene
D. Prostacycline
E. Thromboxane
A. Arachidonic acid
70
Although the prostaglandins are hormone – like substance, they more likely resembles ____ chemically:
A. Proteins
B. Carbohydrates
C. Enzymes
D. Lipids
D. Lipids
71
Which of the following is least describes lipids?
A. Nonpolar
B. Carbon-containing
C. Amphipathic
D. Hydrophilic
D. Hydrophilic
72
Which of the following substances represents an unsaturated fatty acid?
A. Cholesterol
B. Palmitate
C. Stearate
D. Choline
E. Oleate
E. Oleate
73
Triglyceride absorbed into the lymphatic system is transported to the liver as which of the following?
A. Very low density lipoprotein
B. Low density lipoprotein
C. Chylomicrons
D. Liposomes
E. Micelles
C. Chylomicrons
74
Which of the following compounds is an intermediate in the biosynthesis of cholesterol?
A. Squalene
B. Hexosamine
C. Cholic acid
D. Pregnanediol
E. Deoxycholic acid
A. Squalene
75
The major lipids that make up the cell membrane are:
A. Triglycerides
B. Sphingomyelins
C. Phospholipids
D. Fatty acids
E. Steroids
C. Phospholipids
76
Each of the following lipid classes is incorporated into membranes, except:
A. Cholesterol
B. Ganglioside
C. Triglyceride
D. Sphingomyelin
E. Phosphatidylcholine
C. Triglyceride
77
Most abundant and functionally diverse molecules in living systems:
A. Carbohydrates
B. Proteins
C. Lipids
D. Nucleic acids
E. None of these
B. Proteins
78
It is considered as the building blocks of proteins:
A. Purines and pyrimidines
B. Monosaccharides
C. Amino acids
D. Nucleotides
E. Fatty acids and glycerol
C. Amino acids
79
The following describes peptide bond, except:
A. Has a partial double bond characteristics
B. – C(=O)NH–
C. undergoes hydrolytic reaction
D. Formed by the –COOH of an amino acid and the –NH2 of the next amino acid
C. undergoes hydrolytic reaction
80
Which of the following statements about amino acids is correct?
A. Acidic amino acids bear a positive charge at pH = 7.0
B. All amino acids have a chiral carbon
C. Lysine and arginine are basic amino acids
D. All of these
C. Lysine and arginine are basic amino acids
81
Which of the following amino acids contains basic side chain?
A. Histidine
B. Arginine
C. Leucine
D. All of these
E. Both A and B
E. Both A and B
82
Which of the following amino acids do not contain an alipathic side chain?
A. Glycine
B. Valine
C. Proline
D. Leucine
E. Alanine
C. Proline
83
Which amino acid is a major neurotransmitter in the brain?
A. Tyrosine
B. Glutamate
C. Aspartate
D. Serine
E. Tryptophan
B. Glutamate
84
All of the following amino acid contains –OH group except?
A. Histidine
B. Serine
C. Threonine
D. Tyrosine
A. Histidine
85
Which of the following is a sulfur-containing amino acid?
A. Aspartatic acid
B. Asparagine
C. Methionine
D. Glutamic acid
E. Glutamine
C. Methionine
86
Which of the following is an example of basic amino acid?
A. Proline
B. Histidine
C. Tryptophan
D. Phenylalanine
E. Tyrosine
B. Histidine
87
All listed below are aromatic amino acid, except:
A. Histidine
B. Proline
C. Tryptophan
D. Tyrosine
E. Phenylalanine
B. Proline
88
Which of the following has a ketogenic metabolic fate?
A. Leucine
B. Tyrosine
C. Glycine
D. Isoleucine
E. Phenylalanine
A. Leucine
89
Which of the following amino acids contain(s) side chains with sulfur atom?
A. Methionine
B. Cysteine
C. Cytosine
D. Both A and B
E. Both A and C
D. Both A and B
90
Which of the following amino acid has an imino group?
A. Proline
B. Valine
C. Leucine
D. Isoleucine
E. Tyrosine
A. Proline
91
Which of the following amino acid possess a phenolic hydroxyl group?
A. Serine
B. Threonine
C. Tyrosine
D. Both A and B
E. All of these
C. Tyrosine
92
Serotonin, a neurotransmitter is derived from the amino acid ____:
A. Tryptophan
B. Threonine
C. Tyrosine
D. Phenylalanine
A. Tryptophan
93
Identification test for the presence of alpha amino acid and free amino groups?
A. Millon’s Test
B. Xathoproteic Test
C. Hopkin’s Cole Test
D. Ninhydrin Test
E. Molisch Test
D. Ninhydrin Test
94
Identification test for the presence of sulfur such as in cysteine and methionine?
A. Pauly diazo Test
B. Basic Lead Test
C. Hopkin’s Cole Test
D. Biuret Test
E. Salkowski’s Test
B. Basic Lead Test
95
The pH midway between the pKa values in either side of isoelectric species where amino acids exists as neutral species is called as ________.
A. pH determination
B. Henderson-Hasselbach equation
C. Isoelectric point
D. Buffer capacity of amino acids
C. Isoelectric point
96
Calculate the pI of alanine, pK1 (R-COOH) = 2.35; pK2 (R-NH3+) = 9.69
6.02
97
________ are molecules that contain an equal number of ionizable groups of opposite charges and therefore bear a zero net charge.
A. Isoelectric point
B. Amphotheric
C. Neutral amino acid
D. Zwitterions
E. Hydrophobic amino acid
D. Zwitterions
98
Which of the following pairs of amino acid with the indicated side chain is correctly matched?
I. Tryptophan – indole
II. Tyrosine – phenol
III. Arginine – guanidine
A. I, II and III
B. II and III only
C. I and III only
D. I and II only
A. I, II and III
99
The R group of the amino acid “D” is?
A. Hydroxyethyl
B. Hydroxymethyl
C. Carboxyethyl
D. Carboxymethyl
E. Methyl
D. Carboxymethyl
100
Sanger’s Reaction is also known as ____________.
A. Edman’s Test
B. Enzymatic cleavage
C. Dideoxychain termination
D. Splicing
C. Dideoxychain termination
101
This structure of peptides refers to the order of amino acids in the polypeptide chain/s and the location of disufide bonds:
A. Primary
B. Secondary
C. Tertiary
D. Quaternary
A. Primary
102
The overall spatial arrangement of amino acid residues close to one another in the linear sequence of a polypeptide chain:
A. Primary
B. Secondary
C. Tertiary
D. Quaternary
D. Quaternary
103
Secondary Structure includes:
A. Loops
B. Turns
C. Bends
D. B and C only
E. All of these
E. All of these
104
The overall arrangement and interrelationship of various regions or domains, and individual amino acid residues of a single polypeptide chain is ____ structure.
A. Primary
B. Secondary
C. Tertiary
D. Quaternary
C. Tertiary
105
It can prevent the misfolding of nascent polypeptide chain:
A. Proteasome
B. Chaperone
C. Histone
D. Enzymes
E. Hormones
B. Chaperone
106
Non – protein molecules that are often associated with proteins are called:
A. Prosthetic group
B. Side chain
C. Zwitterions
D. Casein
A. Prosthetic group
107
Protein denaturation:
A. Usually irrreversible
B. Unfolding and disorganization of the protein structure
C. Often insoluble (in the form of precipitate)
D. Caused by heat, strong acids & strong base
E. All of these
E. All of these
108
Denaturation of protein is a result of:
A. Cleavage of the peptide bond
B. Formation of hydrogen bond
C. Breakage of hydrogen bond
D. Formation of phosphodiester bond
C. Breakage of hydrogen bond
109
An important protein in contractile muscle:
A. Keratin
B. Myosin
C. Elastin
D. Fibrin
E. Collagen
B. Myosin
110
Alzheimer’s Disease:
A. Genetic defects that impair the synthesis of one polypeptide sub-units of hemoglobin (beta sheet)
B. Glutamic acid is replaced by a valine in the amino acid sequence
C. Misfolding of b - amyloid in human brain tissue
C. Misfolding of b - amyloid in human brain tissue
111
In collagen formation, the amino acids proline and lysine need further modification. What modification is done to these amino acids?
A. Acetylation
B. Methylation
C. Epoxidation
D. Hydroxylation
E. Sulfation
D. Hydroxylation
112
It can stabilize the triple helix structure of collagen
A. Methionine
B. Valine
C. Hydroxyproline
D. Isoleucine
E. Glycine
C. Hydroxyproline
113
Collagen Disease includes the following, except:
A. Ehler’s Danlos Syndrome
B. Menke’s Disease
C. Emphysema
D. Osteogenesis imperfecta
E. Scurvy
C. Emphysema
114
Fibrous proteins are elongated, water – soluble, generally in either alpha-helical, pleated sheet or triple helical forms. Which listed below is an example of fibrous proteins?
A. Hemoglobin
B. Actin
C. Myosin
D. Elastin
E. Both A and B
D. Elastin
115
Major hemoglobin present on adult?
A. a2b2
B. a2g2
C. a2S2
D. a2d2
E. None of these
A. a2b2
116
The product obtained from partial hydrolysis of collagen:
A. Myosin
B. Gelatin
C. Actin
D. Fibrinogen
E. Thrombin
B. Gelatin
117
Which of the following is incorrect about carbon monoxide?
A. Irreversible
B. Fatal
C. Binds tightly with Hb (HbCO)
D. Carbon monoxide poising can be treated with oxygen
A. Irreversible
118
2, 3-bisphosphoglycerate:
A. Also known as 2, 3-diphosphoglycerate
B. Most abundant organic phosphate in the red blood cells
C. Favors/stabilizes the T form
D. Increase concentration is seen on emphysema, high altitudes
E. All of these
E. All of these
119
Xanthoproteic test is a test for:
A. Free amino groups
B. Cysteine
C. Arginine
D. Tyrosine
E. Methionine
D. Tyrosine
120
The ordered steps in protein synthesis is:
I. Activation
II. Elongation
III. Initiation
IV. Termination
A. I – II – III – IV
B. III – II – I – IV
C. I – III – II – IV
D. II – III – I – IV
C. I – III – II – IV
121
Which of the following vitamins is present in coenzymes required in the transfer of amino groups and decarboxylation of amino acids? Its deficiency state is manifested by glossitis, peripheral neuropathy and niacin deficiency:
A. Pyridoxine
B. Niacin
C. Thiamine
D. Riboflavin
C. Thiamine
122
Dialysis is a method of separating proteins on the basis of:
A. Size
B. Solubility
C. Charge
D. Albumin
A. Size
123
The proteins that make fur, wool, claws and feathers:
A. Collagen
B. Silk
C. Keratin
D. Elastin
E. Sulfur
C. Keratin
124
The ribosomal subunit that binds with the initiation complex is ____.
A. 30s
B. 50s
C. 70s
D. 80s
E. 100s
A. 30s
125
Deficiency of this substance favors elastin degradation, thus leads to destruction of the alveolar walls of the lungs resulting to emphysema:
A. a- keratin
B. desmosine crosslink
C. a-1 antitrypsin
D. ascorbate
C. a-1 antitrypsin
126
Which of the following is present on all connective tissues?
A. Mucoids
B. Lipids
C. Albuminoids
D. All
E. None
A. Mucoids
127
Death due to cyanide poisoning results from:
A. Cyanide – hemoglobin complex formation
B. Cyanide – combining with RBC
C. Cyanide – inhibiting cytochrome oxidase
D. Coronary vessel occlusion
C. Cyanide – inhibiting cytochrome oxidase
128
When oxygen binds to hemoglobin, which of the following does it displace in the normal individual?
A. CO
B. CO2
C. CH3
D. Fe+2
E. Fe+3
B. CO2
129
Which of the following symptoms is most closely related to methemoglobinemia?
A. Cyanosis
B. Myopathy
C. Raynaud’s Syndrome
D. Chest pains
E. Both A and B
A. Cyanosis
130
Denaturation usually destroys all of the following bonds in protein, except:
A. Hydrogen bonds
B. Covalent bonds
C. Hydrophobic bonds
D. Electrostatic bonds
B. Covalent bonds
131
The amino acid that contributes to the tertiary structure of a protein by causing a bend when it occurs in the primary sequence is:
A. Leucine
B. Alanine
C. Proline
D. Tyrosine
E. Aspartic acid
C. Proline
132
A mucin is which of the following types of proteins?
A. Simple protein
B. Phosphoprotein
C. Chromoprotein.
D. Nucleoprotein.
E. Glycoprotein
E. Glycoprotein
133
Streptomycin is an antibiotic which inhibits the process of:
A. Translation in eukaryotes
B. Translation in prokaryotes
C. DNA replication in prokaryotes
D. Transcription in eukaryote
E. Transcription in prokaryotes
B. Translation in prokaryotes
134
Each of the following represents an amino acid found in proteins and used directly in the reactions of protein synthesis, except:
A. Proline
B. Arginine
C. Tryptophan
D. Asparagine
E. Hydroxylysine
E. Hydroxylysine
135
Most ________ amino acids are buried away from the water solvent that interacts with the surface of a soluble protein while most ____ side-chains are on the surface of soluble globular proteins:
A. Charged – Hydrophobic
B. Hydrophobic – Charged
C. Hydrophobic – Polar
D. Charged – Polar
C. Hydrophobic – Polar
136
Which amino acid is antagonized by drugs of abuse such as ketamine and phencyclidine and is implicated in schizophrenia:
A. Glycine
B. Aspartate
C. Tryptophan
D. Glutamate
E. Tyrosine
D. Glutamate
137
These substances are proteins that can act as a biological catalyst:
A. Hormones
B. Enzymes
C. Vitamins
D. Minerals
E. Carbohydrates
B. Enzymes
138
Nomenclature of enzymes are based on the following, except:
A. Nature of the general substrate
B. Name of the specific substrate
C. Type of reaction
D. Biosynthetic or catabolic nature
A. Nature of the general substrate
139
Which of the following is true regarding enzymes?
A. Are not reusable
B. Are needed in large amounts
C. Catalyze endergonic reactions only
D. Increase the energy of activation of the reaction
E. Decrease the energy of activation of the reaction
E. Decrease the energy of activation of the reaction
140
Enzymes that catalyze the reaction which joins two molecules or chemical groups:
A. Lyases
B. Ligases
C. Transferases
D. Oxidotransferases
B. Ligases
141
Proteases are examples of what general classification of enzymes?
A. Oxidoreductase
B. Lyases
C. Ligases
D. Hydrolase
E. Transferases
D. Hydrolase
142
The enzyme conformation adapts to the incoming substrate in:
A. Lock and Key Theory
B. Induced Fit Theory
C. Competitive Inhibition
D. Non – competitive inhibition
B. Induced Fit Theory
143
Which of this class of enzymes introduces a double bond by the removal of hydrogen?
A. Dehydrogenase
B. Dehyrolase
C. Decarboxylase
D. Lipase
A. Dehydrogenase
144
The type of inhibition reaction whereby the inhibitor competes with the substrate at the active site:
A. Competitive inhibition
B. Non – competitive inhibition
C. Reversible inhibition
D. Incomplete inhibition
A. Competitive inhibition
145
Milk curdling enzyme present in the gastric juice of infants:
A. Pepsin
B. Rennin
C. Trypsin
D. Maltase
E. Lactase
B. Rennin
146
Optimum temperature for enzyme activity in the body:
A. 40 °C
B. 60°C
C. 37°C
D. 10°C
C. 37°C
147
The activator metal of carbonic anhydrase is:
A. Zinc
B. Iron
C. Molybdenum
D. Magnesium
E. Nickel
A. Zinc
148
Enzymes that catalyze the anaerobic processes of carbohydrate metabolism are found predominantly in which part of a cell?
A. Cytoplasm
B. Membrane
C. Cell wall
D. Nucleus
E. Mitochondria
A. Cytoplasm
149
Enzymes concerned with the citric acid cycle are found in the:
A. Nucleus
B. Ribosomes.
C. Mitochondria
D. Non – particulate cytoplasm
C. Mitochondria
150
Protein kinase regulate the activities of key enzymes through which of the following?
A. Oxidation
B. Hydrolysis
C. Acetylation
D. Phosphorylation
E. Dephosphorylation
D. Phosphorylation
151
Enzymes for electron transport reactions are most active and concentrated in which of the following structures of the animal cell?
A. Nuclei
B. Lysosomes
C. Microsomes
D. Mitochondria
E. All of these
D. Mitochondria
152
Which of the following enzymes is essentially absent from normal mammalian muscle?
A. Glucokinase
B. Phosphorylase
C. Glucose-6-phosphatase
D. Glucose-6-phosphate isomerase
E. Glucose-6-phosphate dehydrogenase
C. Glucose-6-phosphatase
153
Dental plaque arises primarily as a result of enzymatic reactions using which of the following?
A. Sucrose and lipid
B. Sucrose and saliva
C. Glucose and saliva
D. Glucose and protein
B. Sucrose and saliva
154
Which of the following liver enzymes, absent from other tissues, gives the liver an advantage over other cells in taking up glucose after a meal?
A. Glucokinase
B. Aldolase
C. Hexokinase
D. Enolase
E. Glucose-6-phosphatase
A. Glucokinase
155
This is a fermenting enzyme that causes the conversion of monosaccharide into alcohol and carbon dioxide.
A. Carboxylase
B. Invertase
C. Zymase
D. Convertase
C. Zymase
156
A lipolytic enzyme capable of digesting dietary fat.
A. Lipase
B. Fatase
C. Ptyalin
D. Amylase
A. Lipase
157
Pepsinogen is an example of zymogen which is inactive. Pepsinogen is activated by:
A. HCl
B. Enterokinase
C. Ptyalin
D. Lyases
E. Trypsin
A. HCl
158
Which of the following statement does not describe active transport:
A. Movement of a substance across a cell membrane against its concentration gradient
B. Transport of molecules through protein pores
C. Energy dependent
D. Involves electrochemical gradient
B. Transport of molecules through protein pores
159
What is the bond between the 1’ C of the sugar and the nitrogen base?
A. Hydrogen bond
B. Covalent bond
C. Phosphodiester bond
D. Glycosidic bond
E. Both B and C
D. Glycosidic bond
160
Useful for estimating the pH of a buffer solution and find in the equilibrium of pH in acid-base reaction:
A. Michaelis Menten Equation
B. Henderson Hasselbalch Equation
C. Double-reciprocal plot
D. Lineweaver Burk Plot
B. Henderson Hasselbalch Equation
161
These substances are large, complex organic molecules and are usually polymers:
A. Biological molecules
B. Macromolecules
C. Biomolecules
D. All of these
D. All of these
162
Which of the following statements describes catabolism?
I. Breaking down of polymers
II. A hydrolytic (hydrolysis) reaction
III. Maltose = glucose + glucose
A. I only
B. II and III
C. I and III
D. I, II and III
E. III only
D. I, II and III
163
Anabolism is described as:
A. Condensation reaction
B. Dehydration synthesis
C. Building up of monomers
D. Water is one of the product
E. All of these
E. All of these
164
What vitamin can be used in the management of hyperlipidemia?
A. Thiamine
B. Riboflavin
C. Niacin
D. Panthothenic acid
C. Niacin
165
Which of the following is true regarding anabolism?
A. It is involved in the breakdown of larger molecules
B. It consumes energy
C. It commonly involves oxidative reactions
D. It is exergonic
B. It consumes energy
166
Which of the following is/are example(s) of catabolism?
A. Glycogenesis
B. Glycolysis
C. Beta oxidation
D. Both A and B
E. Both B and C
E. Both B and C
167
Which of the following pairing regarding biomolecules is correct?
A. Most common element: C, H, O, N
B. Present in small amount: P, S, Ca, Mg, Na, Cl
C. Trace elements: Fe, Cu, Mn, Zn
D. All are correct
D. All are correct
168
Which of the following pairing is incorrect?
A. Vitamin C: Scurvy
B. Vitamin B1: Wernicke Korsakoff Syndrome
C. Vitamin B3: Pellagra
D. Vitamin A: Night blindness
E. Vitamin E: Osteomalacia
E. Vitamin E: Osteomalacia
169
The major buffer of the extracellular fluid:
A. Bicarbonate-carbon dioxide
B. Amino acids
C. Phosphate
A. Bicarbonate-carbon dioxide
170
Hypertonic solutions will cause the cell to:
A. Swell
B. Shrink
C. Burst
D. Hemolysis
E. Precipitated
B. Shrink
171
DNA is primarily found in the:
A. Cytosol
B. Nucleus
C. Mitochondria
D. A and B
E. B and C
E. B and C
172
It is the entire genetic make up of an organism?
A. Mutation
B. Codon
C. Gene
D. Anti – codon
E. Mammals
C. Gene
173
An example of synthetic DNA:
A. Replicated DNA
B. GMO
C. Gene
D. Chromatin
E. Recombinant DNA
E. Recombinant DNA
174
The type of RNA which serves as template for the amino acid sequence being synthesized:
A. mRNA
B. tRNA
C. rRNA
D. ssDNA
E. dsDNA
A. mRNA
175
A genetic disease due to defective mechanisms for pyrimidine dimmers:
A. Phenylketonuria
B. Xeroderma Pigmentosum
C. Albinism
D. Ataxia telangiectasia
E. Ehler’s Danlos
B. Xeroderma Pigmentosum
176
Which of the following is a STOP Codon?
A. AUG
B. CGC
C. GGA
D. UGA
E. CCC
D. UGA
177
The following are the components of DNA nucleosides, except:
A. Phosphoric acid
B. Sugar
C. Adenine
D. Cytosine
E. Ribose
A. Phosphoric acid
178
Genetic information is stored and carried in all cells by:
A. ssDNA
B. dsDNA
C. dsRNA
D. sscDNA
E. mRNA
B. dsDNA
179
In the secondary structure of RNA:
A. Adenine will always pair with thymine
B. Cytosine will always pair with thymine
C. Cytosine will always pair with uracil
D. Adenine will always pair with uracil
D. Adenine will always pair with uracil
180
The type of RNA molecule that brings amino acids to the site of protein synthesis is:
A. rRNA
B. aRNA
C. mRNA
D. tRNA
E. dsRNA
D. tRNA
181
What is the anti – codon in tRNA that corresponds to the codon ACF in mRNA?
A. UGC
B. TGC
C. GCA
D. CGU
E. UGA
A. UGC
182
This type of mutation occurs when the codon containing the changed base may become a termination codon:
A. Nonsense mutation
B. Silent mutation
C. Misense mutation
D. None of these
A. Nonsense mutation
183
The result of a point mutation that occurs when UCA (coding for serine) is converted to UCU (also coding for serine) is called:
A. Nonsense mutation
B. Silent mutation
C. Misense mutation
D. None of these
B. Silent mutation
184
The most abundant and most common form of DNA:
A. A-DNA
B. Z-DNA
C. E-DNA
D. B-DNA
E. X-DNA
D. B-DNA
185
Central Dogma concept wherein the RNA molecule is used as template for the synthesis of DNA molecule:
A. Transcription
B. Translation
C. Mutation
D. Coding
A. Transcription
186
Which is not a product of hydrolysis of nucleotide?
A. N – base
B. Sugar
C. Fat
D. Phosphate
E. A, B, and D only
C. Fat
187
These are discontinuous stretches in which the lagging strand is initially synthesized during DNA replication:
A. Okazaki Fragment
B. Enhancer
C. Primer
D. Opener
E. DNA Ligase
A. Okazaki Fragment
188
The complementary strand of CGACCTTGATCGA:
A. TCGTTCCAGCTAG
B. GCTGGAACTAGCT
C. AGCAAGGTCGAAC
D. ATCAAGGTCGATC
B. GCTGGAACTAGCT
189
Which of the following is correct about the Watson-Crick model of DNA?
A. The backbone of each DNA strand is a repeating sugar-phosphate polymer
B. The strands of DNA are anti-parallel, spiraling around the helix axis in opposite directions
C. The sequences of bases in the two strands are determined by hydrogen bonding between adenine and thymine or guanine and cytosine
D. The sugar involved in the backbone structure is deoxyribose
E. All are correct features of DNA structure
E. All are correct features of DNA structure
190
This step repeats until reaching a stop codon:
A. Transcription
B. Elongation
C. Translation
D. Termination
B. Elongation
191
The steps of central states:
A. Replication, Translation, Transcription
B. Replication, Transcription, Transmission
C. Replication, Transcription, Translation
D. Transcription, Translation, Replication
C. Replication, Transcription, Translation
192
What is wobble?
A. The ability of certain anticodons to pair with codons that differ at the third base
B. An error in translation induced by streptomycin
C. A mechanism that allows for a peptide extension in the 50s sub-unit of the ribosome
D. Thermal motions leading to local denaturation of the DNA double helix
A. The ability of certain anticodons to pair with codons that differ at the third base
193
The process by which genetic information flows from RNA to protein is:
A. Mutation
B. Replication
C. Translation
D. Transcription
C. Translation
194
The nucleic acids, RNA and DNA plays an important role in the biosynthesis of proteins. This sugar is:
A. Glucose
B. Sucrose
C. Fructose
D. Ribose
E. Maltose
D. Ribose
195
Which of the following enzymes or processes ensures that the correct amino acid is incorporated for a particular codon during protein synthesis?
A. Amino Acyl-tRNA synthetase
B. Ribosomal protein synthesis
C. Post-transcription splicing
D. RNA synthetase
E. Helicase
A. Amino Acyl-tRNA synthetase
196
The termination of synthesis of a polypeptide is believed to involve:
A. Nonsense codon
B. Anticodon-codon interaction
C. tRNA which cannot bind amino acids.
D. Hydrolysis of messenger RNA.
A. Nonsense codon
197
In prokaryotic protein synthesis, the elongation factor G serves to:
A. Form the initiation complex
B. Facilitate the binding of Fmet tRNA
C. Translocate the growing peptide chain and to move the ribosome along the mRNA
D. Prevent the larger ribosomal subunits from binding with those that are smaller
C. Translocate the growing peptide chain and to move the ribosome along the mRNA
198
Which of the following bonds link the monomeric units of nucleic acids?
A. Ionic
B. Peptide
C. Thioester
D. Glycosidic
E. Phosphodiester
E. Phosphodiester
199
In the DNA molecule, guanine on 1 strand is joined to cytosine on the complementary strand by which of the following bonds?
A. Amide
B. 1 Hydrogen
C. 2 Hydrogen
D. 3 Hydrogen
E. Phosphodiester
D. 3 Hydrogen
200
As DNA is denatured, each of the following events take place, except:
A. Total G-C content of total DNA increasing
B. UV light absorption increasing
C. Complementary strands becoming random coils
D. Base stacking becoming disrupted
E. Hydrogen bond breaking
A. Total G-C content of total DNA increasing
201
The function of which of the following types of nucleic acid is to activate and select specific amino acids for protein synthesis?
A. rRNA
B. mRNA
C. cDNA
D. tRNA
E. hnRNA
D. tRNA
202
If the molar percentage of A (adenine) in a native DNA specimen is 22%, then what is the molar content of G (guanine)?
A. 22%
B. 28%
C. 44%
D. 56%
E. 78%
B. 28%
203
The degenerate nature of the genetic code implies:
A. a common tRNA for at least two amino acids
B. that a remarkable degree of inaccuracy occurs in transcription
C. the existence of multiple codons for each amino acid
D. the existence of multiple species of ribosomes for control of messenger translation
C. the existence of multiple codons for each amino acid
204
Transcription is the cellular process of making:
A. new DNA
B. RNA from DNA
C. proteins from amino acids by way of RNA
D. none of the above
B. RNA from DNA
205
DNA damage by ultraviolet light is due to:
A. alkylation of the guanine in DNA
B. excessive unwinding of the DNA molecule
C. frequent replacement in the DNA molecule of purines by pyrimidines
D. induction of dimerization by way of covalent bonds between adjacent thymine groups
D. induction of dimerization by way of covalent bonds between adjacent thymine groups
206
Each of the following is involved in gene cloning, except:
A. DNA ligase
B. RNA polymerase
C. DNA polymerase I
D. Restriction nucleases
E. Reverse transcriptase
B. RNA polymerase
207
Plasmid vectors suitable for cloning have which of the following characteristics?
A. Must be able to replicate synchronously with the host chromosome
B. Several unique recognition sequences for one restriction enzyme
C. Two genes conferring resistance to different antibiotics
D. Large size to facilitate plasmid’s entry into cells
C. Two genes conferring resistance to different antibiotics
208
If the anticodon on transfer-RNA is 5’ACG3’, then which of the following is its corresponding codon on messenger-RNA?
A. 5’ CGT 3’
B. 5’ CGU 3’
C. 5’ TGC 3’
D. 5’ UAG 3’
E. 5’ UGC 3’
B. 5’ CGU 3’
209
DNA that is complementary to mRNA can be made using which of the following?
A. a plasmid
B. DNA ligase
C. a retrovirus
D. RNA polymerase
E. Reverse transcriptase
E. Reverse transcriptase
210
Which of the following enzymes seals nicks in DNA?
A. Exonuclease
B. Endonuclease
C. DNA polymerase
D. RNA polymerase
E. Ligase
E. Ligase
211
Which of the following represents the consequence of the fact that DNA strands are complementary?
A. Hairpin loop structures can be generated
B. They will always have identical sequences
C. Separated strands are able to re-associate
D. They cannot get back together once separated
C. Separated strands are able to re-associate
212
Which of the following BEST describes the major function of histones?
A. Unwind DNA
B. Activate genes
C. Stabilize DNA in a compact form
D. Remove exons during RNA splicing.
E. Stabilize RNA during transcription
C. Stabilize DNA in a compact form
213
Which of the following BEST describes restriction enzymes?
A. Exonucleases
B. Topiosomerases
C. Enzymes that degrade RNA
D. Non-specific endonucleases
E. Site-specific endonucleases
E. Site-specific endonucleases
214
When only one base is replaced in the DNA sequence, the mutation is said to be a:
A. Frame shift mutation
B. Deletion
C. Inversion
D. Point mutation
E. Translocation
D. Point mutation
215
The common metabolic pathway:
A. Glycolysis
B. Beta oxidation
C. Kreb’s Cycle
D. Glucogenesis
C. Kreb’s Cycle
216
It is regarded as the universal biological energy currency:
A. ATP
B. GTP
C. cAMP
D. UTP
E. cGMP
A. ATP
217
It is a metabolic process occurring at the “cross roads: of metabolism (citric acid cycle):
A. Anabolic
B. Catabolic
C. Amphibolic
D. All of the choices
C. Amphibolic
218
Glycolysis produces ____ ATPs:
A. 2
B. 6
C. 36
D. 32
A. 2
219
The common product of carbohydrate, protein and fat catabolism is:
A. Glucose
B. Amino acids
C. Acetyl CoA
D. Fatty acids
C. Acetyl CoA
220
The final product of glycolysis is:
A. Pyruvate
B. Oxaloacetate
C. Citrate
D. Acetyl CoA
A. Pyruvate
221
Glucogenesis involves the formation of glucose from:
A. Non – carbohydrate sources
B. Pentose
C. Aldohexose
D. Ketohexose
E. Polysaccharides
A. Non – carbohydrate sources
222
The conversion of an amino acid to sugar is
A. Gluconeogenesis
B. Glycolysis
C. Glycogenesis
D. Glycogenolysis
E. Glucogenesis
A. Gluconeogenesis
223
Glucose, amino acid and fatty acid enter the citric acid cycle by their conversion into:
A. Pyruvate
B. Acetyl CoA
C. Malonyl CoA
D. Palmitic acid
B. Acetyl CoA
224
Gluconeogenesis is the formation of new glucose. The enzymes responsible for this are only confined to some organs, which includes:
A. Muscles
B. Liver
C. Kidneys
D. A and B
E. B and C
E. B and C
225
The term “anaerobic phase” of glucose oxidation is used to designate series of reaction known as:
A. Glycolysis
B. Glycogenesis
C. Glycogenolysis
D. Both A and B
A. Glycolysis
226
What enzyme in gluconeogenesis is employed to bypass the hexokinase reaction, which is the interconversion of glucose to glucose – 6 – phosphate?
A. Pyruvate carboxylase
B. PEP carboxykinae
C. Fructose biphosphatase
D. Glucose – 6 – phosphatase
D. Glucose – 6 – phosphatase
227
The pentose phosphate pathway occurs in the ____ of liver, muscle and kidney
A. Inner mitochondria
B. Outer mitochondria
C. Cytosol
D. Ribosomes
E. Tissues
C. Cytosol
228
Which of the following is/are the main goals of Pentose Phosphate Pathway?
A. Produce ribose – 5 – Phosphate for nucleotide synthesis
B. Produce NADPH and NADP for fatty acid and steroid biosynthesis
C. To interconvert pentose and hexoses
D. All of these
E. A and B only
D. All of these
229
Which of the following enzymes is present only in the liver and kidney and not in the muscle?
A. Pyruvate carboxylase
B. PEP carboxykinase
C. Fructose biphosphatase
D. Glucose – 6 - phosphatase
D. Glucose – 6 - phosphatase
230
This refers to aldose – ketose interconversion:
A. Tautomerization
B. Isomerism
C. Mutarotation
D. Conjugation
A. Tautomerization
231
This is the only reaction coupled with substrate level phosphorylation in the TCA.
A. Citrate to isocitrate
B. Isocitrate to alpha – ketoglutarate
C. Succinyl CoA to succinate
D. Succinate to fumarate
C. Succinyl CoA to succinate
232
This is the only reaction in TCA that involves FAD/FADH2?
A. Citrate to isocitrate
B. Isocitrate to alpha – ketoglutarate
C. Succinyl CoA to succinate
D. Succinate to fumarate
D. Succinate to fumarate
233
How many ATPs are produced for every acetyl CoA oxidized?
A. 10
B. 12
C. 14
D. 8
E. 6
B. 12
234
How many ATPs are produced in the reduction of one mole of NAD to NADH?
A. 2
B. 3
C. 4
D. 12
E. 8
B. 3
235
How many ATPs are produced in the conversion of one mole of FADH2 to FAD?
A. 2
B. 3
C. 4
D. 12
E. 8
A. 2
236
The total net ATP produced in aerobic glycolysis is ________ ATPs per mole of hexose, depending on which shuttle predominates in the transport of NAD/NADH.
A. 4 to 6
B. 6 to 8
C. 4 to 8
D. 8 to 10
B. 6 to 8
237
Which of the following occur(s) in the cytosol?
A. TCA
B. Glycolysis
C. PPP
D. A and B
E. B and C
E. B and C
238
The condition that lowers the pH of the blood due to starvation is called ____:
A. Acidosis
B. Alkalosis
C. Hyperglycemia
D. Glycosuria
A. Acidosis
239
The chief end product of purine metabolism:
A. Carbon dioxide
B. Ammonia
C. Urea
D. Uric acid
D. Uric acid
240
This substance accumulates in the muscle as a result of vigorous exercise:
A. Lactulose
B. Amino acid
C. Glycogen
D. Lactic acid
D. Lactic acid
241
Which substance yields the largest number of calories per gram?
A. Carbohydrates
B. Proteins
C. Minerals
D. Fats
E. Vitamins
D. Fats
242
How many ATPs can one molecule of palmitic acid can be yielded via beta-oxidation?
A. 128
B. 129
C. 130
D. 131
E. 132
B. 129
243
The enzymes involved in ethanol metabolism:
A. Phosphorylase
B. Dehydrogenase
C. Lipase
D. Ketase
E. Thiokinase
B. Dehydrogenase
244
Amino acids that are not immediately incorporated into new protein are:
A. Stored in the muscles
B. Stored in the liver
C. Recycled in the blood
D. Stored in tissues
E. Rapidly degraded
E. Rapidly degraded
245
Most nitrogenous waste is converted to urea because:
I. Ammonia and uric acid are toxic
II. Urea is highly soluble
III. Urea is non toxic
A. I only
B. III only
C. II and III
D. I and III
E. I, II and III
E. I, II and III
246
A number of catabolic pathways are allosterically inhibited by an increase in the concentration of which of the following?
A. ADP
B. AMP
C. ATP
D. NAD+
E. Pyruvate
C. ATP
247
Which of the following represents the chemical substance that is the immediate source of energy for muscle contraction?
A. Glycogen
B. Acetyl CoA
C. Lactic acid
D. Creatine phosphate
E. Adenosine triphosphate
E. Adenosine triphosphate
248
The tricarboxylic acid cycle is initiated by the condensation of which of the following two molecules?
A. Pyruvate and malate
B. NAD+ and oxaloacetate
C. NAD+ and oxalosuccinate
D. Acetyl coenzyme A and oxaloacetate
E. Acetyl coenzyme A and oxalosuccinate
D. Acetyl coenzyme A and oxaloacetate
249
Acids found in the citric acid (Krebs) cycle are:
A. Glutamic acid and succinic acid
B. Glucuronic acid and aspartic acid
C. Oxaloacetic acid and aspartic acid
D. Oxaloacetic acid and pyruvic acid
E. Oxaloacetic acid and α-ketoglutaric acid
E. Oxaloacetic acid and α-ketoglutaric acid
250
If protein is catabolized for energy, then MOST of the energy is derived from which of the following?
A. Urea production
B. Oxidative deamination
C. Transamination reactions
D. Cleavage of peptide bonds
E. Oxidation of α-keto acids derived from amino acids
E. Oxidation of α-keto acids derived from amino acids
251
After prolonged acidosis, which of the following represents the nitrogenous product that is excreted in high amounts in the urine?
A. Urea
B. Ammonia
C. Uric acid
D. Creatinine
E. Aspartic acid
B. Ammonia
252
Excessive utilization of fats by the body as a source of energy during disturbances in carbohydrate metabolism can lead to all of the following conditions, except:
A. Ketosis
B. Acidosis
C. Ketonuria
D. Alkalosis
D. Alkalosis
253
The final step in the complete metabolism of fat is carried out by means of:
A. Anaerobic glycolysis
B. Tricarboxylic acid cycle
C. Reductive fixation of CO2
D. Hexose monophosphate shunt
E. Krebs-Henseleit (urea) cycle
B. Tricarboxylic acid cycle
254
Which of the following is necessary for de novo synthesis of cholesterol?
A. NAD+
B. NADH
C. NADP+
D. NADPH
E. FADH2
D. NADPH
255
Ribose phosphate needed for nucleic acid synthesis can be derived from:
A. Gluconeogenesis
B. Pentose phosphate pathway
C. Krebs’ tricarboxylic acid cycle
D. Decarboxylation of aromatic amino acids
E. One-carbon transfer from tetrahydrofolate derivatives
B. Pentose phosphate pathway
256
The pathway of extramitochondrial synthesis of even-numbered fatty acids differs from that of the catabolism of fatty acids in that:
A. Malonyl CoA is an intermediate in synthesis
B. Acyl carrier protein is needed in catabolism
C. No flavoprotein enzymes are required for catabolism
D. Propionyl CoA may serve as an intermediate in synthesis
A. Malonyl CoA is an intermediate in synthesis
257
After functioning in the small intestines, the largest portion of bile salts are:
A. excreted in the feces
B. reabsorbed into the central lacteal
C. destroyed by bacteria in the large intestines
D. reabsorbed into the portal circulation and reused
E. removed from the circulation by the kidneys and excreted in the urine
D. reabsorbed into the portal circulation and reused
258
Which of the following mechanisms operates in liver cells to regulate breakdown of glycogen?
A. Zymogen activation
B. Phosphorylation of phosphorylase b to phosphorylase a
C. Induction of phosphorylase b by an inducer
D. Inhibition of adenylate cyclase
B. Phosphorylation of phosphorylase b to phosphorylase a
259
Each of the following is expected to be active during fatty acid biosynthesis, except:
A. Tricarboxylic acid cycle
B. Pyruvate dehydrogenase
C. Amino acid catabolism
D. Beta oxidation
E. Glycolysis
D. Beta oxidation
260
Symptoms of photophobia/photosensitivity are most likely associated with which metabolic disorder?
A. Phenylketonuria
B. Alkaptonuria
C. Albinism
D. Maple syrup urine disease
C. Albinism
261
Which of the following is a ketone body?
A. Glycerol
B. Glucagon
C. Acetyl CoA
D. Acetoacetate
E. Phosphatidycholine
D. Acetoacetate
262
Chemical messengers produced by the endocrine glands:
A. Genes
B. Hormones
C. Vitamins
D. Enzymes
B. Hormones
263
Which among the following vitamins may cause extensive vasoconstriction and elevated blood pressure and calcinosis of soft tissues when taken in excess?
A. Vitamin A
B. Vitamin B3
C. Vitamin B6
D. Vitamin D
D. Vitamin D
264
Which hormone can regulate the level of blood sodium level?
A. Corticosteroid
B. Cortisol
C. Aldosterone
D. Sterol
C. Aldosterone
265
Condition wherein bile pigment is present in excess in the blood?
A. Jaundice
B. Hepatitis
C. Cirrhosis
D. Cystic fibrosis
A. Jaundice
266
The substance responsible for the emulsion of fats is:
A. Gastric acid
B. Bile acids
C. Pepsin
D. Trypsin
B. Bile acids
267
Which vitamin can be used in the management of hyperlipidemia:
A. Thiamine
B. Niacin
C. Riboflavin
D. Panthothenic acid
B. Niacin
268
Growth hormone is also known as:
A. Thyrotropic hormone
B. Somatotropin
C. Gonadotropin
D. Luteinizing hormone
E. ACTH
B. Somatotropin
269
Separates from cells when blood is coagulated:
A. Fibrinogen
B. Serum
C. Plasma
D. Thrombin
B. Serum
270
A hormone which stimulates glycogenesis:
A. Insulin
B. Glucagons
C. Epinephrine
D. Vasopressin
A. Insulin
271
Chemicals extracted from organism such as bacteria and can inhibit growth or destroy other microorganism:
A. Vitamins
B. Bacteria
C. Hormone
D. Antibiotics
E. Both A and C
D. Antibiotics
272
FSH and interstitial cell – stimulating hormones are produced by the:
A. Islets of langerhands
B. Thymus gland
C. Thyroid glands
D. Pineal gland
E. Pituitary glands
E. Pituitary glands
273
Which of the following statements is (are) true about insulin:
I. Insulin is a hormone
II. Insulin is a protein
III. Produced by the beta cells of the pancreas
IV. Insulin is rapidly distributed throughout extracellular fluid
A. I, III and IV only
B. I and II only
C. I, II, III and IV
D. I, II and IV
C. I, II, III and IV
274
The protein precursor of thyroxine is:
A. Ornithine
B. Threonine
C. Tryptophan
D. Thyroglobulin
D. Thyroglobulin
275
Each molecule of vitamin B12 contains an atom of:
A. Potassium
B. Copper
C. Cobalt
D. Nickel
E. Zinc
C. Cobalt
276
A substance found commonly in fermented foods that can be toxic when monoamine oxidase inhibitors are used:
A. Adenosine diphosphate
B. Adenosine triphosphate
C. Tyramine
D. Histidine
E. Phenylalamine
C. Tyramine
277
Somastatin is also known as:
A. Growth hormone
B. HMG CoA Reductase
C. Vasopressin
D. Growth hormone release inhibitor
E. Desmopressin
D. Growth hormone release inhibitor
278
Absence of anti-diuretic hormone in the body causes:
A. Kidney failure
B. Diabetes insipidus
C. Diabetes mellitus
D. Nephritis
E. Hypertensive crisis
B. Diabetes insipidus
279
Which of the following conditions are associated with increase blood ammonia levels?
A. Reye’s syndrome
B. Liver disease
C. Neuropathy
D. Dermatitis
E. Streptococcal infection
B. Liver disease
280
Myxedema is a malfunction of which gland?
A. Anterior pituitary
B. Posterior pituitary
C. Adrenal
D. Parathyroid
E. Thyroid
E. Thyroid
281
Male luteinizing hormone:
A. is not present
B. has no effect
C. Suppress testosterone production
D. Stimulates testosterone production
D. Stimulates testosterone production
282
Which of the following conditions are usually measured via the D-xylose test?
A. Malabsorption
B. Brain tumor
C. Glucose metabolism
D. Renal dysfunction
E. Thyroid function
A. Malabsorption
283
Which of the following hormones is a polypeptide?
A. Epinephrine
B. Testosterone
C. Progesterone
D. Triiodotyronine
E. Follicle-stimulating hormone
E. Follicle-stimulating hormone
284
Iodine is primarily important in the biochemical synthesis of:
A. ACTH
B. Thyroxin
C. Adrenalin
D. Calcitonin
E. Parathyroid hormone
B. Thyroxin
285
Which of the following hormones is NOT synthesized from cholesterol?
A. Progesterone
B. Testosterone
C. Estradiol
D. Cortisol
E. Relaxin
E. Relaxin
286
In which of the following combinations is the name of the hormone, its chemical type and its tissue of origin correctly matched?
A. Aldosterone – Peptide – Pancreas
B. Glucagon – Peptide – Adrenal cortex
C. Epinephrine – Steroid – Adrenal medulla
D. ACTH – Polypeptide – Adrenal cortex
E. Vasopressin – Peptide – Posterior pituitary
E. Vasopressin – Peptide – Posterior pituitary
287
Each of the following characterizes a peptide hormone, except:
A. Stored in secretory granules
B. Synthesized in a precursor form
C. Binds to intracellular receptors
D. Acts by generating a second messenger
E. Usually transported unbound in plasma
D. Acts by generating a second messenger
288
The intracellular, “second” messenger for many peptide and polypeptide hormones is:
A. AMP
B. ATP
C. cAMP
D. adenylate cyclase
E. a cytoplasmic receptor.
C. cAMP
289
Which of the following generates a slowly developing long-term response in target tissues by binding to an intracellular receptor?
A. Glucagon
B. Estrogen
C. Prolactin
D. Growth hormone
E. Parathyroid hormone
B. Estrogen
290
Epinephrine causes an elevation in cAMP levels in muscle cells which in turn activate:
A. ATPase
B. Adenyl cyclase
C. Glycogen synthetase
D. Glycogen phosphorylase
E. Glycogen phosphorylase phosphatase
D. Glycogen phosphorylase
291
Which of the following hormones does NOT induce activation of adenylate cyclase?
A. Insulin
B. Glucagon
C. Epinephrine
D. Parathyroid hormone
A. Insulin
292
The hyperglycemic effect of glucagon is mediated primarily through:
A. the growth hormone
B. muscle glycolysis
C. liver glycogenolysis
D. inhibition of cortisol action
E. enhanced glucose reabsorption by renal tubules
C. liver glycogenolysis
293
Two hormones which act similarly to increase glycogen and lipid breakdown as well as cyclic AMP synthesis are:
A. Insulin and calcitonin
B. Glucagon and epinephrine
C. Aldosterone and testosterone
D. Parathyroid hormone and glucagon
B. Glucagon and epinephrine
294
Which of the following takes place as proinsulin is converted to insulin?
A. Disulfide bonds are formed
B. Disulfide bonds are broken
C. The polypeptide chain is lengthened
D. A segment of the polypeptide chain is removed
D. A segment of the polypeptide chain is removed
295
Inhibition of lipolysis, stimulation of protein synthesis and increased entry of glucose into muscles and adipose tissues are biologic actions of the hormone:
A. Insulin
B. Cortisol
C. Glucagons
D. Epinephrine
E. Testosterone
A. Insulin
296
Which of the following is a principal action of insulin?
A. To mobilize lipid deposits
B. To enhance cell permeability to glucose
C. To decrease cell permeability to glucose
D. To conserve glucose by breaking down amino acids
B. To enhance cell permeability to glucose
297
Aldosterone is normally associated with partial regulation of which of the following processes?
A. Sodium balance
B. Gluconeogenesis
C. Lipid digestion
D. Protein degradation
E. Carbohydrate metabolism
A. Sodium balance
298
Which of the following BEST explains the primary action of anti – diuretic hormone?
A. It decreases the activity of the Na-K pump in the distal tubule
B. It increases the H2O permeability of the collecting ducts and the distal tubules
C. It decreases the pore size of the distal tubules and the collecting ducts
D. It decreases the glomerular filtration rate
E. It inhibits the action of glutaminase
B. It increases the H2O permeability of the collecting ducts and the distal tubules
299
The parathyroid hormone acts in the body by:
A. Decreasing absorption of calcium in the intestinal tract
B. Accelerating the removal of calcium and PO4^-3 from the skeleton but not from the teeth
C. Stimulating gluconeogenesis in the liver
D. Decreasing the excretion of sodium and chloride
E. All of the above
B. Accelerating the removal of calcium and PO4^-3 from the skeleton but not from the teeth
300
Hyperparathyroidism is marked by:
A. Chronic tetany
B. High blood calcium level
C. Retention of phosphates by the kidneys
D. Storage of excess minerals in the bones
E. Increased irritability of excitable tissues
B. High blood calcium level
301
The low serum phosphate level in hyperparathyroidism is caused by:
A. increased renal loss of phosphate
B. decreased absorption of phosphate
C. increased deposition of calcium phosphate in bone
D. increased reabsorption of calcium phosphate from bone
A. increased renal loss of phosphate
302
Hydrolysis of thyroglobulin liberates a number of iodinated compounds. Two are considered thyroid hormones. These are:
A. Tyrosine and thyronine
B. Tyrosine and diiodotyrosine
C. Thyroxin and triiodothyronine
D. Thyroxin and triiodotyrosine
C. Thyroxin and triiodothyronine
303
Secretin functions in digestion of proteins by increasing:
A. flow of bile
B. Secretion of pepsin
C. Flow of pancreatic juice
D. Secretion of carboxypeptidase
C. Flow of pancreatic juice
304
Thyroid hormones, glucocorticoids and gonadal steroids are similar in that each
A. is derived from cholesterol
B. is derived from amino acids
C. acts on only one target organ or tissue
D. is released in response to signals from the hypothalamic-anterior pituitary complex
E. is released in response to signals from the hypothalamic-posterior pituitary complex
D. is released in response to signals from the hypothalamic-anterior pituitary complex
305
Which of the following describes the principal mechanism by which glucocorticoids stimulate their target cells?
A. They activate specific genes
B. They activate initiation factors for protein synthesis
C. They increase the intracellular Ca++ concentration
D. They allosterically modify adenylate cyclase activity
E. They bind to cell membrane receptors and activate adenylate cyclase
A. They activate specific genes
306
The gallbladder is caused to contract by the hormone:
A. Gastrin
B. Secretin
C. Pancreozymin
D. Enterogastrone
E. Cholecystokinin
E. Cholecystokinin
307
Androgens are produced in the testis and:
A. Adrenal cortex
B. Thyroid
C. Adrenal medulla
D. Pituitary
E. Hypothalamus
A. Adrenal cortex
308
Cytochromes are useful in which reactions?
A. Oxidation reduction
B. Transamination
C. Decarboxylation
D. Hydrolysis
E. Deamination
A. Oxidation reduction
309
A necessary precursor of visual pigment is:
A. Retinal
B. Retinol
C. Ergosterol
D. Cholecalciferol
A. Retinal
310
Which of the following terms describes a reduced number of platelets?
A. Thrombocytopenia
B. Leukopenia
C. Leukocytosis
D. Thrombophlebitis
E. Thrombocytosis
A. Thrombocytopenia
311
Tay-Sach disease is associated with an inborn error of metabolism involving a specific enzyme which normally degrades a particular molecule in the gray matter. This enzyme acts on which of the following?
A. Polysaccharides
B. Acylglycerols
C. Gangliosides
D. Fatty acids
E. Proteins
C. Gangliosides
312
The most biologically important physiochemical property of connective tissue which is regulated by its mucopolysaccharide molecules is:
A. Viscosity
B. Buffering capacity
C. Solubility in dilute acids
D. Supersaturation with calcium ions
A. Viscosity
313
Which of the following compounds is NOT involved in coagulation of blood?
A. Fe+2
B. Ca+2
C. Prothrombin
D. Fibrinogen
E. Thromboplastin
A. Fe+2
314
Which of the following ions is involved in blood clotting?
A. Iron
B. Sodium
C. Calcium
D. Potassium
C. Calcium
315
A deficiency in vitamin K would affect blood clotting chiefly by:
A. decreasing prothrombin production
B. preventing the contraction of the clot
C. preventing the reaction of thrombin with fibrinogen
D. preventing the conversion of fibrinogen to fibrin
E. preventing the conversion of prothrombin to thrombin
A. decreasing prothrombin production
316
Which of the following represents the normal substrate of thrombin?
A. Fibrin
B. Thrombospondin
C. Prothrombin
D. Thromboplastin
E. Fibrinogen
E. Fibrinogen
317
Platelets play an important role in hemostasis. Which of the following describes this role?
A. They convert fibrinogen to fibrin
B. They agglutinate and plug small, ruptured vessels
C. They initiate fibrinolysis in thrombosis
D. They supply fibrin stabilizing factor
E. They supply proconvertin for thromboplastin activation
B. They agglutinate and plug small, ruptured vessels
318
Administration of heparin to a human results in symptoms similar to vitamin K deficiency in that both conditions result in:
A. release of lipoprotein lipase to the blood and rapid clearance of chylomicrons
B. and increase in bleeding time due to lack of thrombin formation
C. retardation of fibrinogen synthesis by the liver
D. elevated non-esterified fatty acids which chelate serum calcium, thus retarding blood clotting
B. and increase in bleeding time due to lack of thrombin formation
319
The unique amino acid composition of collagen is reflected in the high content of:
A. Valine, threonine, and lysine
B. Desmosine, glycine, and proline
C. Cysteine, hydroxylysine, and proline
D. Cysteine, tyrosine, and phenylalanine
E. Glycine, proline, and hydroxyproline
E. Glycine, proline, and hydroxyproline
320
Which of the following is MOST likely to promote depolymerization of extracellular matrix?
A. Cortisone
B. Collagenase
C. Chymotrypsin
D. Hyaluronidase
D. Hyaluronidase
321
Which of the following vitamins is essential for the normal elaboration and maintenance of bone matrix, cartilage, and dentin?
A. Niacin
B. Vitamin E
C. Ascorbic acid
D. Pantothenic acid
C. Ascorbic acid
322
Which of the following tests is specific for the presence of free amino acid groups?
A. Biuret tests
B. Hopkin’s Cole test
C. Ninhydrin test
D. Xanthoproteic test
E. Sakaguchi test
C. Ninhydrin test
323
Which among the items listed below best associated to vitamin A?
A. Sunshine vitamin
B. Beri-beri
C. Pyridoxine
D. Night blindness
E. Bleeding problems
D. Night blindness
324
Folic acid deficiency can lead to:
A. Aplastic anemia
B. Microcytic anemia
C. Megaloblastic anemia
D. Macrocytic anemia
C. Megaloblastic anemia
325
The general test for carbohydrates based on the dehydration of the sugar to form furfural derivatives when the sugar is treated with concentrated sulfuric acid producing a violet ring between two layers:
A. Fehling’s Test
B. Molisch Test
C. Benedict’s Test
D. Tollen’s Test
B. Molisch Test
326
This is the most abundant immunoglobulin in the blood.
A. IgG
B. IgA
C. IgM
D. IgE
E. IgD
A. IgG
327
This is also known as protein-calorie malnutrition. It is a state resulting from the chronic deficiency of calories, which can occur even in the presence of adequate intake of protein:
A. Marasmus
B. Obesity
C. Hemochromatosis
D. Kwashiorkor
A. Marasmus
328
The digestion of carbohydrates begins in the ____
A. Mouth
B. Stomach
C. Small intestine
D. Duodenum
A. Mouth
