DNA & Protein Synthesis
What molecule stores the genetic instructions cells use to make proteins?
DNA
What process makes mRNA from DNA?
Transcription
Which RNA carries instructions to the ribosome?
mRNA
What does gene expression mean?
Using a gene to make a functional product, such as a protein.
What is a mutation?
A change in genetic information.
What is the order of information flow in protein synthesis? (3 steps)
DNA → RNA → Protein
DNA template: TAC-GGA. What is the mRNA sequence?
AUG-CCU
Which RNA delivers amino acids to the ribosome?
tRNA
Why do muscle and skin cells have the SAME DNA but different functions?
They express different genes.
Original: ACG-TTA-GCC. Mutated: ACG-TTC-AGC. What mutation occurred?
Insertion
What determines the order of amino acids in a protein?
The DNA base sequence determines the mRNA codons, which determine the order of amino acids in a protein.
What process stops if ribosomes cannot function?
Translation
How many codons are in AUG-GCU-CCA?
3 codons
A plant makes more protective proteins during drought. What influenced its gene expression?
The environment
Original: ATG-CCT. Mutated: ATG-CAT. What mutation occurred?
Substitution
Why can a change in DNA affect an organism's traits?
It may change a protein's structure or function.
What makes up the ribosome and helps in building proteins?
rRNA
What tRNA anticodon pairs with mRNA codon GCA?
CGU
How can cells make different proteins without changing their DNA?
By turning different genes on and off.
GAA changes to GAG, but both code for Glu. What type of mutation is this?
Silent mutation
Why can bacteria produce a protein using a human gene?
The genetic code is nearly universal.
If RNA polymerase stops working, what process is mainly affected? Will a protein still be made?
Transcription, No
What happens if tRNA cannot carry amino acids?
Translation cannot build proteins normally
A mutation prevents a gene from being turned off when its protein is no longer needed. What is the most likely result?
The protein will continue to be made
A deletion causes an early stop codon. What happens to the protein?
Produces a shortened, potentially nonfunctional protein.