C785 Readiness Exam
The LEP gene codes for an anorexigenic hormone. Interestingly, breastfeeding has
been shown to alter methylation of the promoter of this gene, leading to increased LEP
expression. What is likely happening in response to breastfeeding? –
Breastfeeding decreases the methylation of the promoter of the LEP gene, increasing
the spacing between nucleosomes.
A patient with xeroderma pigmentosum is prone to developing multiple skin cancers
starting in childhood. This occurs because of a mutation in a gene that codes for
enzymes that help repair DNA damage through the nucleotide excision repair (NER)
pathways. How does NER differ from other repair mechanisms? In NER: -
The error in one strand of DNA is removed as well as several nucleotides on either side
of the error. The gap that was removed is filled in by DNA polymerase
Several components of cigarette smoke, including benzopyrene, insert themselves
(intercalate) into the DNA and lead to several types of mutations such as frameshift
mutations, including both insertions and deletion. Which of the following repair pathways
would be used to repair this type of damage? –
Nucleotide excision repair is used to repair deletions, insertions, and helix-distorting
lesions, such as thymine dimers
Interaction between the two amino acids shown below can help stabilize the structure of
a protein. What kind of interaction is this? –
Hydrophobic Interaction
Which of the following forces can lead to aggregation as a result of protein misfolding? –
Hydrophobic interactions
Which of the following statements about protein structure and stability is true? –
Ionic bonds between the side chains of the charged amino acids stabilize the protein
structure
Primary structure consists of the order of ______ in a protein. These are held together
with ______ bonds that are formed by a ______ reaction. - Amino acids, peptide,
dehydration
What type of reaction breaks peptide bonds apart? –
, Hydrolysis Reaction
A particular amino acid in a protein helps to stabilize the protein by forming disulfide
bonds. What amino acid is likely to form this type of bond? –
Cysteine
Aggregation of proteins is the main reason behind many neurodegenerative diseases.
Which one of the following mutations will likely cause a neurodegenerative disease? –
Replacing a polar amino acid with a non polar amino acid
Chymotrypsin is a digestive enzyme that has optimal activity at a pH of 7.8 and a
temperature of 37 degrees Celsius. Which of the following statements is true? –
The reaction rate for chymotrypsin at a pH of 9.5 is lower than the reaction rate for
chymotrypsin at a pH of 7.8.
A patient presents with a fever of 110°F. Which interaction(s) would be disrupted within
a neuronal protein if the fever is not resolved quickly? –
Hydrophobic Interactions
A diabetic patient is suffering from ketoacidosis. Which interaction(s) could be disrupted
within the patientʼs hemoglobin due to this condition. Select all that apply. –
Hydrogen Bond Ionic Bonds
Which of the following forces can lead to aggregation as a result of protein misfolding? –
Hydrophobic Interactions
Which of the following are true about a misfolded protein? Select all that apply. –
It will lose its normal function.
.It can lose its primary function
It can cause protein aggregation.
Patients with carbon monoxide (CO) poisoning may exhibit pink or cherry red skin,
mucus membranes and nails. Which statement accurately describes hemoglobin's role
in CO poisoning? –
hemoglobin binds CO with a higher affinity than oxygen and stabilizes the R-state
In which of the following patients is the planar conformation of the heme group in
hemoglobin favored? –
The LEP gene codes for an anorexigenic hormone. Interestingly, breastfeeding has
been shown to alter methylation of the promoter of this gene, leading to increased LEP
expression. What is likely happening in response to breastfeeding? –
Breastfeeding decreases the methylation of the promoter of the LEP gene, increasing
the spacing between nucleosomes.
A patient with xeroderma pigmentosum is prone to developing multiple skin cancers
starting in childhood. This occurs because of a mutation in a gene that codes for
enzymes that help repair DNA damage through the nucleotide excision repair (NER)
pathways. How does NER differ from other repair mechanisms? In NER: -
The error in one strand of DNA is removed as well as several nucleotides on either side
of the error. The gap that was removed is filled in by DNA polymerase
Several components of cigarette smoke, including benzopyrene, insert themselves
(intercalate) into the DNA and lead to several types of mutations such as frameshift
mutations, including both insertions and deletion. Which of the following repair pathways
would be used to repair this type of damage? –
Nucleotide excision repair is used to repair deletions, insertions, and helix-distorting
lesions, such as thymine dimers
Interaction between the two amino acids shown below can help stabilize the structure of
a protein. What kind of interaction is this? –
Hydrophobic Interaction
Which of the following forces can lead to aggregation as a result of protein misfolding? –
Hydrophobic interactions
Which of the following statements about protein structure and stability is true? –
Ionic bonds between the side chains of the charged amino acids stabilize the protein
structure
Primary structure consists of the order of ______ in a protein. These are held together
with ______ bonds that are formed by a ______ reaction. - Amino acids, peptide,
dehydration
What type of reaction breaks peptide bonds apart? –
, Hydrolysis Reaction
A particular amino acid in a protein helps to stabilize the protein by forming disulfide
bonds. What amino acid is likely to form this type of bond? –
Cysteine
Aggregation of proteins is the main reason behind many neurodegenerative diseases.
Which one of the following mutations will likely cause a neurodegenerative disease? –
Replacing a polar amino acid with a non polar amino acid
Chymotrypsin is a digestive enzyme that has optimal activity at a pH of 7.8 and a
temperature of 37 degrees Celsius. Which of the following statements is true? –
The reaction rate for chymotrypsin at a pH of 9.5 is lower than the reaction rate for
chymotrypsin at a pH of 7.8.
A patient presents with a fever of 110°F. Which interaction(s) would be disrupted within
a neuronal protein if the fever is not resolved quickly? –
Hydrophobic Interactions
A diabetic patient is suffering from ketoacidosis. Which interaction(s) could be disrupted
within the patientʼs hemoglobin due to this condition. Select all that apply. –
Hydrogen Bond Ionic Bonds
Which of the following forces can lead to aggregation as a result of protein misfolding? –
Hydrophobic Interactions
Which of the following are true about a misfolded protein? Select all that apply. –
It will lose its normal function.
.It can lose its primary function
It can cause protein aggregation.
Patients with carbon monoxide (CO) poisoning may exhibit pink or cherry red skin,
mucus membranes and nails. Which statement accurately describes hemoglobin's role
in CO poisoning? –
hemoglobin binds CO with a higher affinity than oxygen and stabilizes the R-state
In which of the following patients is the planar conformation of the heme group in
hemoglobin favored? –
