DNA
What is the shape of the DNA molecule?
The DNA molecule is shaped like a double helix.
What are the three main types of RNA and their primary functions?
mRNA (messenger RNA) carries genetic information from DNA to ribosomes, tRNA (transfer RNA) brings amino acids to the ribosome, and rRNA (ribosomal RNA) forms the core of ribosome’s structure.
What is the process called where mRNA is synthesized from a DNA template?
Transcription
What is an epigenetic change?
An epigenetic change is a modification that alters gene expression without changing the DNA sequence itself.
Write the complementary DNA strand for the following sequence: ATCGGCTA
TAGCCGAT
Which of the nitrogenous bases are complementary in DNA?
Adenine and Thymine
Cytosine and Guanine
How does the sugar in RNA differ from the sugar in DNA?
RNA contains ribose, while DNA contains deoxyribose.
What happens during translation in protein synthesis?
The mRNA sequence is used to build a polypeptide chain (protein) by linking amino acids together.
How do mutations differ from epigenetic changes?
Mutations are changes in the DNA sequence itself, whereas epigenetic changes affect gene expression without altering the DNA sequence.
Transcribe the following DNA sequence into mRNA: TACGGTAC
AUGCCAUG
What is the primary function of DNA polymerase during DNA replication?
DNA polymerase adds nucleotides to the growing DNA strand, synthesizing the new strand.
Which base is found in RNA but not in DNA?
Uracil
In what part of the cell does translation occur?
Translation occurs in the cytoplasm, specifically on the ribosomes.
mutations
Write the mRNA sequence that would be transcribed from the DNA template strand GCTAGC
CGAUCG
What is the role of helicase in DNA replication?
Helicase unwinds and separates the double-stranded DNA.
What is the function of mRNA in protein synthesis?
mRNA carries the genetic code from DNA to the ribosome for protein synthesis
During translation, what is the role of tRNA?
tRNA carries specific amino acids to the ribosome and matches its anticodon with the mRNA codon to ensure the correct amino acids are added to the growing polypeptide chain.
DNA methylation or histone modification are examples of what?
epigenetic modifications
Given the mRNA sequence AUG-UCC-GAA, provide the corresponding amino acids using the standard genetic code.
Methionine (Met), Serine (Ser), Glutamic acid (Glu)
During DNA replication, what is the term for the short segments of DNA synthesized on the lagging strand?
Okazaki fragments.
How does the structure of RNA differ from DNA in terms of strand number?
RNA is typically single-stranded, while DNA is double-stranded.
What is the significance of the start codon in mRNA?
The start codon (AUG) signals the beginning of translation and specifies the first amino acid (Methionine) in the polypeptide chain.
How can epigenetic modifications influence an organism’s phenotype?
Epigenetic modifications can turn genes on or off, affecting the traits that are expressed without changing the underlying DNA sequence.
Transcribe and translate the DNA sequence: ACG-TTT-GCG, to provide the corresponding amino acids.
Cysteine (Cys), Lysine (Lys), Arginine (Arg).