What is mutation
Change in DNA sequence
What is the mRNA sequence from the following DNA sequence?
GGTAAC
CCAUUG
What is the complementary DNA sequence from the following sequence?
GGTAAC
CCATTG
What is a start codon?
AUH
Define point mutation.
Change in a single base sequence
Which enzyme adds RNA molecules to make mRNA?
RNA polymerase
How many bases translates to a single amino acid?
3
Which mutations below cause a frameshift?
Substitution
Deletion
Insertion
Deletion and Insertion
State 2 differences between DNA and RNA
DNA single stranded/RNA double
DNA contains thymine/RNA contains uracil
DNA has a deoxyribose sugar/RNA has a ribose sugar
Name 2 enzymes involved in DNA replication and state their function.
Helicase - untwists and unzips DNA
DNA Polymerase - add free nucleotides to template DNA
Ligase - forms covalent bond between sugar phosphate backbone
Topoisomerase - receives tension whilst untwisted DNA
RNA primes - add RNA nucleotides
Name the 3 bases found on a tRNA molecule and a mRNA molecule. What is the relationship between the 2 regions?
tRNA - anticodon
mRNA - codon
Complementary base pairing
Why is frameshift mutations the most dangerous amongst all mutations?
Every single amino acid after the mutation changes.
What makes up ribosomes?
RNA + other proteins
What is the difference between translocation and inversion mutations?
Translocation is a DNA segment inserted from another chromosome.
Inversion is switching of DNA segments within the same chromosome
Describe ONE RNA editing that occurs before mRNA leaves the nucleus?
Splicing of exon and introns
Adding a cap
Adding a poly A tail
Describe ONE way your cells prevent mutations occurring to your DNA.
Protected by nuclear membrane
Tightly packed around histone
Both strands double bonded preventing other molecules bonding.
If an mRNA molecule was 15 bases long from start to stop, how many amino acid sequences would there be in the resulting protein chain?
15/3 = 5
5-1 stop codon = 4 amino acids long