1. What is epigenetics?
A) The study of genetic mutations
B) The study of changes in gene expression without changes to the DNA sequence
C) The study of genetic recombination
D) The study of genetic engineering
Answer: B) The study of changes in gene expression without changes to the DNA sequence
2. Which of the following is NOT an epigenetic mechanism?
A) DNA methylation
B) Histone acetylation
C) RNA splicing
D) Non-coding RNA regulation
Answer: C) RNA splicing
3. What is the role of DNA methylation in epigenetics?
A) It adds methyl groups to histone proteins
B) It modifies the DNA sequence
C) It regulates gene expression by adding methyl groups to cytosine bases
D) It removes methyl groups from DNA
Answer: C) It regulates gene expression by adding methyl groups to cytosine bases
4. Histone acetylation involves:
A) Adding acetyl groups to histone proteins
B) Adding methyl groups to histone proteins
C) Removing acetyl groups from histone proteins
D) Removing methyl groups from histone proteins
Answer: A) Adding acetyl groups to histone proteins
5. Which enzyme is responsible for DNA methylation?
A) DNA polymerase
B) DNA ligase
C) DNA methyltransferase
D) RNA polymerase
Answer: C) DNA methyltransferase
6. What is the function of non-coding RNAs in epigenetics?
A) They code for proteins
B) They regulate gene expression by binding to DNA or RNA
C) They catalyze DNA replication
D) They are involved in DNA repair
Answer: B) They regulate gene expression by binding to DNA or RNA
7. Which of the following is NOT an example of an epigenetic change?
A) DNA mutation
B) DNA methylation
C) Histone modification
D) Non-coding RNA regulation
Answer: A) DNA mutation
8. Epigenetic changes can be influenced by:
A) Genetics only
B) Environmental factors only
C) Both genetics and environmental factors
D) Diet only
Answer: C) Both genetics and environmental factors
9. Inheritance of epigenetic changes:
A) Can only occur through the maternal line
B) Can only occur through the paternal line
C) Can occur through both maternal and paternal lines
D) Cannot occur
Answer: C) Can occur through both maternal and paternal lines
10. Which of the following is NOT a potential consequence of aberrant epigenetic regulation?
A) Cancer
B) Neurological disorders
C) Cardiovascular diseases
D) Single-gene disorders
Answer: D) Single-gene disorders
11. What is the term for the modification of histone proteins that results in a more compact chromatin structure?
A) Histone acetylation
B) Histone methylation
C) Histone phosphorylation
D) Histone ubiquitination
Answer: B) Histone methylation
12. Which of the following is NOT a type of non-coding RNA involved in epigenetic regulation?
A) microRNA (miRNA)
B) Transfer RNA (tRNA)
C) Small interfering RNA (siRNA)
D) Long non-coding RNA (lncRNA)
Answer: B) Transfer RNA (tRNA)
13. How do epigenetic changes affect gene expression?
A) By altering the DNA sequence
B) By changing the order of nucleotides in mRNA
C) By modifying the structure of chromatin
D) By increasing the rate of transcription
Answer: C) By modifying the structure of chromatin
14. Which of the following environmental factors can influence epigenetic changes?
A) Diet
B) Stress
C) Exposure to toxins
D) All of the above
Answer: D) All of the above
15. What is the function of chromatin remodeling complexes in epigenetics?
A) To add methyl groups to DNA
B) To modify histone proteins
C) To unwind DNA for transcription
D) To repair DNA damage
Answer: C) To unwind DNA for transcription
16. What is the role of histone deacetylases (HDACs) in epigenetics?
A) To remove acetyl groups from histone proteins
B) To add acetyl groups to histone proteins
C) To remove methyl groups from DNA
D) To add methyl groups to histone proteins
Answer: A) To remove acetyl groups from histone proteins
17. Which of the following is NOT a potential application of epigenetics?
A) Cancer therapy
B) Agricultural improvement
C) Forensic analysis
D) Space exploration
Answer: D) Space exploration
18. What is the significance of epigenetic changes in development?
A) They determine the genetic code of an organism
B) They regulate the expression of genes required for development
C) They prevent mutations from occurring
D) They encode information about an organism’s environment
Answer: B) They regulate the expression of genes required for development
19. What is the function of DNA demethylases?
A) To add methyl groups to DNA
B) To remove methyl groups from DNA
C) To add acetyl groups to histone proteins
D) To remove acetyl groups from histone proteins
Answer: B) To remove methyl groups from DNA
20. Which of the following is NOT a type of epigenetic modification?
A) DNA methylation
B) Histone phosphorylation
C) Non-coding RNA regulation
D) DNA replication
Answer: D) DNA replication
21. How do epigenetic changes influence cell differentiation?
A) By preventing cells from differentiating
B) By promoting the expression of genes required for differentiation
C) By inhibiting the expression of genes required for differentiation
D) By altering the DNA sequence
Answer: B) By promoting the expression of genes required for differentiation
22. What is the role of chromatin modification in X-chromosome inactivation?
A) To prevent X-chromosome inactivation
B) To activate the X-chromosome
C) To silence one of the X-chromosomes in female mammals
D) To promote X-chromosome replication
Answer: C) To silence one of the X-chromosomes in female mammals
23. Which of the following is NOT a mechanism by which non-coding RNAs regulate gene expression?
A) mRNA degradation
B) Histone modification
C) Transcriptional interference
D) Alternative splicing
Answer: B) Histone modification
24. What is the function of small interfering RNAs (siRNAs) in epigenetics?
A) To inhibit gene expression by targeting specific mRNAs for degradation
B) To promote gene expression by enhancing transcription
C) To modify histone proteins
D) To silence transposable elements
Answer: A) To inhibit gene expression by targeting specific mRNAs for degradation
25. What is the primary role of long non-coding RNAs (lncRNAs) in epigenetics?
A) To regulate gene expression by binding to DNA
B) To act as templates for protein synthesis
C) To catalyze chemical reactions
D) To modulate chromatin structure and gene expression
Answer: D) To modulate chromatin structure and gene expression
26. Which of the following is NOT an example of epigenetic reprogramming?
A) Embryonic development
B) Somatic cell nuclear transfer
C) Induced pluripotent stem cell generation
D) Mitosis
Answer: D) Mitosis
27. How do environmental factors such as diet influence epigenetic changes?
A) By altering the DNA sequence
B) By directly modifying histone proteins
C) By affecting the activity of epigenetic enzymes
D) By promoting DNA replication
Answer: C) By affecting the activity of epigenetic enzymes
28. What is the role of genomic imprinting in epigenetics?
A) To silence one copy of a gene depending on its parental origin
B) To promote the expression of imprinted genes
C) To prevent DNA replication
D) To repair DNA damage
Answer: A) To silence one copy of a gene depending on its parental origin
29. What is the function of microRNAs (miRNAs) in epigenetics?
A) To promote the expression of target genes
B) To silence the expression of target genes
C) To modify histone proteins
D) To repair DNA damage
Answer: B) To silence the expression of target genes
30. How do epigenetic changes contribute to aging?
A) By preventing cellular senescence
B) By promoting DNA repair
C) By altering gene expression patterns
D) By increasing telomere length
Answer: C) By altering gene expression patterns
31. Which of the following is NOT an example of epigenetic regulation in plants?
A) DNA methylation
B) Histone modification
C) Non-coding RNA regulation
D) Telomere shortening
Answer: D) Telomere shortening
32. How do epigenetic changes influence behavior?
A) By directly altering the DNA sequence
B) By modulating neurotransmitter levels
C) By promoting synaptic plasticity
D) By regulating gene expression in response to environmental stimuli
Answer: D) By regulating gene expression in response to environmental stimuli
33. What is the role of histone methylation in gene silencing?
A) It adds acetyl groups to histone proteins
B) It removes acetyl groups from histone proteins
C) It adds methyl groups to histone proteins, leading to a closed chromatin state
D) It removes methyl groups from histone proteins
Answer: C) It adds methyl groups to histone proteins, leading to a closed chromatin state
34. What is the role of chromatin remodeling in gene expression?
A) To condense chromatin and prevent gene expression
B) To unwind chromatin and make genes accessible for transcription
C) To add methyl groups to DNA
D) To synthesize new DNA
Answer: B) To unwind chromatin and make genes accessible for transcription
35. How does environmental stress affect epigenetic modifications?
A) By causing DNA mutations
B) By altering histone modifications and DNA methylation patterns
C) By enhancing DNA replication
D) By inhibiting gene expression
Answer: B) By altering histone modifications and DNA methylation patterns
36. What is the role of DNA methyltransferases in epigenetics?
A) To remove methyl groups from DNA
B) To add methyl groups to DNA
C) To modify histone proteins
D) To synthesize RNA
Answer: B) To add methyl groups to DNA
37. How do histone modifications affect gene expression?
A) By directly changing the DNA sequence
B) By influencing the accessibility of DNA for transcription
C) By removing non-coding RNAs
D) By altering the structure of ribosomes
Answer: B) By influencing the accessibility of DNA for transcription
38. What is the significance of epigenetic memory in cell differentiation?
A) It prevents cells from differentiating
B) It maintains gene expression patterns across cell divisions
C) It induces genetic mutations
D) It promotes random gene expression
Answer: B) It maintains gene expression patterns across cell divisions
39. How do epigenetic changes contribute to cancer development?
A) By causing mutations in oncogenes
B) By altering the expression of genes involved in cell growth and apoptosis
C) By preventing DNA replication
D) By enhancing the immune response
Answer: B) By altering the expression of genes involved in cell growth and apoptosis
40. What is the primary function of DNA demethylation in development?
A) To add methyl groups to DNA
B) To remove methyl groups from DNA and activate gene expression
C) To modify histone proteins
D) To repair DNA damage
Answer: B) To remove methyl groups from DNA and activate gene expression