BIO CHEM 2 Flashcards
Amino acids sequence in DNA can be determined by the order of their
rRNA
tRNA
Nucleotides
mRNA
Nucleotides
Which of the following is a Sanger’s reagent?
asd1-fluoro-2, 4-dinitrobenzene
dfsd1-fluoro-2, 3-dinitrobenzene
gh1-fluoro-2, 4-trinitrobenzene
jut1-fluoro-2, 3-trinitrobenzene
asd1-fluoro-2, 4-dinitrobenzene
The amino acid sequences of thousands of different proteins from many species have been determined using principles first developed by
Edman
Sanger
Mendel
Watson and Crick
Sanger
Which of the following compound is not involved in Edman degradation?
Phenylisothiocyanate
CF3COOH
FDNB
Phenylthiocarbonyl
FDNB
Which of the following statements is false?
Oxidation of cysteine residue with performic acid is done to break disulfide bond in proteins
Reduction of cysteine residue with dithiothreitol is done to break disulfide bond in proteins
Reduction of cysteine residue with performic acid is done to break disulfide bond in proteins
Reduced cysteine is further acetylated by iodoacetate
Reduction of cysteine residue with performic acid is done to break disulfide bond in proteins
Cleaving of peptide chain is done by
Trypsin
Tyrosine
Tryptophan
Arginine
Trypsin
Which of the following is the correct order of sequencing?
Cleaving, sequencing and ordering
Sequencing, ordering and cleaving
Ordering, cleaving and sequencing
Ordering, sequencing and cleaving
Cleaving, sequencing and ordering
Edman degradation is used for
Identifying N-terminal amino acids
Identifying C-terminal amino acids
Identifying amino acid
Identifying carbohydrates
Identifying N-terminal amino acids
What best summarizes the MALDI method by which gas phase ions are produced for mass spectrometry?
Sample is hit by a low energy xenon beam.
Sample is forced through a narrow capillary tube and solvent rapidly evaporates.
Sample is embedded in a crystalline matrix and bombarded by laser beams.
Sample is heated and then bombarded by electrons
Sample is embedded in a crystalline matrix and bombarded by laser beams.
Which of the following is Edman reagent?
Phenylisothiocyanate
CF3COOH
FDNB
Phenylthiocarbonyl
Phenylisothiocyanate
Which of the following does not affect the stability of a α-helix?
Electrostatic repulsion
Bulkiness
Interaction between R groups spaced three residues apart
Occurrence of alanine and glycine residues
Occurrence of alanine and glycine residues
Which of the following is not true about secondary protein structure?
The hydrophilic/hydrophobic character of amino acid residues is important to secondary structure.
The ability of peptide bonds to form intramolecular hydrogen bonds is important to secondary structure.
The alpha helix, beta pleated sheet and beta turns are examples of protein secondary structure.
The steric influence of amino acid residues is important to secondary structure.
The hydrophilic/hydrophobic character of amino acid residues is important to secondary structure.
pleated sheets are the examples of
Primary structure
Secondary structure
Tertiary structure
Quaternary structure
Secondary structure
A coiled peptide chain held in place by hydrogen bonding between peptide bonds in the same chain is
Primary structure
α-helix
β-pleated sheets
Tertiary structure
α-helix
A structure that has hydrogen bonds between polypeptide chains arranged side by side is
Primary structure
α-helix
β-pleated sheets
Tertiary structure
β-pleated sheets
Which of the following are known as helix breakers?
Proline and glycine
Isoleucine and leucine
Valine
Threonine
Proline and glycine
Which of the following is false about NMR spectroscopy?
NMR is an abbreviated form of Nuclear Magnetic Resonance
The intramolecular magnetic field around an atom in a molecule changes the resonance frequency giving structural information about the atom
The intermolecular magnetic field around an atom in a molecule changes the resonance frequency giving structural information about the atom
It is a technique that exploits magnetic properties of atomic nuclei
The intermolecular magnetic field around an atom in a molecule changes the resonance frequency giving structural information about the atom
Which of the statements is false about multiple sequence alignment?
Both protein and nucleic acid secondary structures can be used
More useful in RNA
These alignments can be made more accurate by the inclusion of secondary structure information
A significant increase in accuracy
More useful in RNA
Secondary structure is defined by
Hydrogen bonding
Vander Waals forces
Covalent bonding
Ionic bonding
Hydrogen bonding
Which of the following is false statement?
α-Keratin is α helical
Collagen is α helical
Hemoglobin has a quaternary structure
α-Keratin is β pleated structure
α-Keratin is β pleated structure
Fibroin is rich in
Alanine and Glycine
Alanine
Glycine
Pro
Alanine and Glycine
Which of the following bonds are not involved in tertiary type of protein structure?
Disulfide bond
Hydrogen bonding
Salt bridges
Hydrophilic interactions
Hydrophilic interactions
Which of the following does not possess a quaternary structure?
Myoglobin
Lactate dehydrogenase
Immunoglobin M
Creatine Phospho Kinase
Myoglobin
Which of the following is abundantly found in collagen?
Glycine
Serine
Alanine
Tryptophan
Glycine
Which of the following is first determined as oligomer?
Myoglobin
Collagen
Keratin
Hemoglobin
Hemoglobin
Which of the following is false?
Lysozyme has S-S linkage
Ribonuclease has S-S linkage
Heme group in cytochrome c is covalently linked to the protein on two sides
Ribonuclease has SH-SH linkage
Ribonuclease has SH-SH linkage
Which of the following enzyme is secreted by the pancreas?
Ribonuclease
Lysozyme
Cytochrome c
Myoglobin
Ribonuclease
Which of the following is a component of mitochondria?
Ribonuclease
Lysozyme
Cytochrome c
Myoglobin
Cytochrome c
Which of the following serves as bactericidal agent?
Ribonuclease
Lysozyme
Cytochrome c
Myoglobin
Lysozyme
Which of the following is false about fibrous protein?
It is in rod or wire like shape
Keratin and collagen are the best examples
Hemoglobin is the best example
It provides structural support for cells and tissues
Hemoglobin is the best example
Which of the following forces is favorable for protein folding?
Hydrophobic interactions
Hydrogen bonding
Vander Waals forces
Ionic bonding
Hydrophobic interactions
A process by which a protein structure assumes its functional shape or conformation is
Denaturing
Folding
Synthesis
Hydrolysis
Folding
Process of folding does not depend on
Concentration of salts
pH
Solute
Solvent
Solute
Which of the following cannot denature a protein?
Iodoacetic acid
SDS detergent
Urea
Heating to 90°C
Iodoacetic acid
Which of the following is a function of chaperone protein?
It degrades proteins that have folded improperly
It provide a template for how the proteins should fold
It rescues proteins that have folded improperly and allows them to refold properly
It degrades proteins that have folded properly
It rescues proteins that have folded improperly and allows them to refold properly
As folding progresses which of the following does not take place?
Entropy decreases
Amount of protein in native state increases
Free energy increases
Amount of protein in native state decreases
Amount of protein in native state decreases
Which of the following are chaperons in E.coli?
Hsp70
Hsp40
DnaA
DnaK and DnaJ
DnaK and DnaJ
Which of the following about spontaneous folding is false?
It involves initial formation of highly compact structure
It involves initial formation of a local secondary structure
It is essentially a random process
It may be defective in some human diseases
It is essentially a random process
Protein A will fold into its native state only when protein B is also present in the solution. However protein B can fold itself into native confirmation without the presence of protein A. Which of the following is true?
Protein B serves as precursor for protein A
Protein B serves as molecular chaperon for protein A
Protein B serves as ligand for protein A
Protein B serves as structural motif for protein A
Protein B serves as precursor for protein A