DNA vs RNA
What is the purpose of the weak hydrogen bonds between bases in DNA?
(Allows DNA to unzip easily for replication and transcription.)
What are the two main processes of protein synthesis? What is made in each?
Transcription- Makes mRNA
Translation-Make Protien
What would happen if a ribosome skipped one nucleotide while reading mRNA?
(It would cause a frameshift mutation, changing all amino acids after the mistake.)
Why are different genes expressed in different cells?
(Cells turn genes on or off based on their function and environment)
What type of mutation can be passed from parent to offspring?
(Chromosomal mutation)
What base does RNA have that replaces thymine in DNA?
(Uracil)
What does the idea "form follows function" relate to protiens?
Their shape compliments or matches their job.
Think red blood cells shaped like a bucket for O2.
What type of mutation is more likely to be harmful? Why?
(A frameshift—changes all amino acids.)
Why do cancer treatments like chemotherapy target rapidly dividing cells?
(Cancer cells divide more frequently, making them more vulnerable to drugs that disrupt division.)
Can a mutation in skin cells be inherited? Why or why not?
(No, because it’s a gene (body cell or somatic) mutation – it only affects that individual not offspring)
What sugar does DNA contain that RNA does not?
(Deoxyribose)
How many bases are in a codon, and what does a codon code for?
(3 bases, codes for 1 amino acid)
How could a nonsense mutation impact protein function?
(It introduces a stop codon too early, resulting in a shortened, nonfunctional protein.)
Explain how gene regulation ensures cells function properly.
(It controls which genes are active in each cell, so only necessary proteins are made)
What is one example of a chromosomal mutation?
(Deletion, duplication, inversion, translocation)
How does the structure of RNA polymerase contribute to its function in transcription?
(Allows complementary RNA nucleotides to be assembled- mRNA)
If a DNA sequence is TAC-GGC-ATA, what would the corresponding mRNA sequence be?
(AUG-CCG-UAU)
Name one environmental factor that can cause mutations
(Radiation, chemicals, viruses, replication errors)
How does a mutation in p53, the “guardian of the genome,” increase cancer risk?
(p53 normally stops the cell cycle or triggers apoptosis if DNA is damaged; without it, cells with mutations keep dividing.)
True or False: Some mutations have no effect on an organism.
(True – silent mutations don’t change the protein)
Name two structural and two functional differences between DNA and RNA.
Structure: DNA = double-stranded, RNA = single-stranded; DNA has thymine, RNA has uracil.
Function: DNA stores genetic information, RNA helps make proteins.)
What would happen if a cell lacked a stop codon during translation? What would this result in?
(The ribosome wouldn’t stop translating, leading to faulty or excessively long proteins.)
Why might a missense mutation in hemoglobin (protein in red blood cells) lead to sickle cell disease?
(It alters the protein’s shape, making red blood cells rigid and less efficient at carrying oxygen.)
Why do cancer treatments like chemotherapy target rapidly dividing cells?
(Cancer cells divide more frequently, making them more vulnerable to drugs that disrupt division.)
Why are mutations important for evolution?
(They create genetic variation, which can lead to beneficial traits over time)