CHapteer 13 Flashcards
The process of using DNA to produce complementary RNA molecules is called_________
transcription
The sequence of ____ in mRNA complements the sequence in the DNA template
bases
RNA is formed in the _______ and then travels to the ____________
nucleus—cytoplasm
The enzyme _______________binds to DNA during transcription.
RNA polymerase
RNA polymerase binds to regions of DNA called
Promoters
Portions of RNA that are cut out and discarded
Introns
_____ are spliced together to make the final mRNA
extrons
A specific sequence of bases in DNA carries the directions for forming a ______________ a chain of amino acids.
polypeptide
The sequence of bases in mRNA is the
genetic code
The four bases ___, ___, ___, ___ act as “letters”
A C G U
Each “word” in mRNA is known as a ____________
codon
The process of decoding of an mRNA message into a protein a ribosome is
translation (occurs in cytoplasm)
What begins when a ribosome attaches to an mRNA molecule
translation
Process in which DNA, RNA, and proteins are involved in putting genetic information into action in living cells
Gene expression
Changes in DNA
mutations
Involve changes in nucleotide
point mutations (occurs at single point in sequence)
3 types of point mutations:
substitution, insertion, deletion
1 base is changed to a different base
substitution ( changing 1 amino acid to a protein) sometimes they do not silent mutation
1 base is inserted into DNA sequence
insertion
1 base is removed from DNA sequence
deletion
Insertion and deletion are both types of
frameshift mutation
shift of reading frame of genetic message…affects every amino acid after point of change- protein does not function due to improper folding
Frameshift mutation
changes an amino acid to a stop codon
nonsense mutation
Chemical or physical agents that cause mutations
mutagens
pesticides, tobacco, environmental pollutants
chemical agents
x-ray, uv radiation
physical agents
RNA contains
ribose, phosphate, uracil
DNA contains
dioxide ribose thymine
What are 3 types of RNA
rRNA
mRNA
tRNA
7 AA - 7 codons - ____ bases
21
DNA —> RNA —->
Protein
What causes translation to stop?
stop codon
