DNA Structure
What is a gene?
A gene is a sequence of DNA nucleotides that acts as a recipe for a specific protein.
What does transcription make?
mRNA
What is an anti-codon?
A 3 nucleotide sequence on a tRNA that matches to a specific mRNA codon
What is a mutation?
Any change to an organism's DNA/genome.
If a DNA sequence changes, what is the FIRST process affected?
Transcription
Which two parts form the backbone?
phosphate and sugar
Where does transcription take place?
Nucleus
The bonds that hold amino acids together
Peptide bonds
How can a mutation affect a protein?
It can change the amino acid sequence and alter function
What are some factors that can cause a mutation?
Environmental factors: chemicals, radiation, sun, food, & viruses
One DNA strand has a base sequence GTCCATA. The base sequence on the second strand of DNA is...
CAGGTAT
A single stranded piece of a DNA has the following bases: ACTGAG. What is the matching sequence on its RNA transcript?
UGACUC
What is another name for a chain of amino acids
Polypeptide
What is a silent mutation?
A mutation that does not change the amino acid
A nucleotide is accidentally deleted, what kind of mutation is this?
Frameshift mutation
If the DNA has 30% adenosine, this is the percent composition of guanine.
20%
What do we call the monomers of DNA and RNA?
Nucleotides
What is the central dogma?
DNA → RNA → Protein
Why might two different DNA sequences produce the same protein?
Redundancy in the genetic code (multiple codons for same amino acid)
If a protein folds incorrectly, what level(s) of structure could be affected?
Secondary, tertiary, and/or quaternary
These two men are credited with figuring out the shape & structure of DNA. They used a photograph taken by a female fellow scientist (double points if you can name the female scientist).
James Watson and Francis Crick (+points for Rosalind Franklin)
Why is mRNA necessary?
Because DNA is too big to leave the nucleus and mRNA brings the message to the ribosomes
What does tRNA do?
When a tRNA finds a matching mRNA codon, it drops off the attached amino acid to be used in protein.
A codon is changed from UAC to UAA, why type of point mutation is this?
Nonsense
A codon is changed from UUC to UCC, why type of point mutation is this?