Biology chapter 13 study guide

amino acids
organic compounds

anti codons
tRNA molecule’s 3 unpaired bases

central dogma

chromosomal mutation
gene mutations that produce changes in whole chromosomes

Each three letter code

point mutations in which one base is removed from the DNA sequence… If a nuceotide is deleted the bases are still read in groups of three, but those groupings shift in every codon that follows the mutation

portions of RNA that are cut out and discarded- coding regions of RNA

spliced together to make the final mRNA- coding regions of RNA

frameshift mutations
instertions/ deletions. They change the “reading frame.” of the genetic message. They can change every amino acid that follows the point of the mutation. They can alter a protein so much that it is unable to perform its normal functions

gene expression
the way in which DNA, RNA, and proteins are involved in putting genetic information into action in living cells.

genetic code
The RNA code that we have is known as
the genetic code.
•We read this genetic code three letters at a time in order to translate this message into
an amino acid

nucleotide is being added to the DNA sequence

messenger RNA
copy of DNA. gives the “message” to other parts of the cell. Carries instructions for polypeptide synthesis from nucleus to ribosomes in the cytoplasm.

missense mutation
point mutation. Different amino acid is given.

chemical or physical agents in the environment. Chemical mutagens cause a mutation in environment like pollutants, and physical are IN our environment, like radiation

heritable changes in genetic information

nonsense mutation
change in the base, where the amino acid turns into a stop

nucleic acids
long slightly acidic molecules originally identified in the cell nuclei. They are made up of smaller subunits linked together to form a long chain

peptide bond
covalent chemical bond formed between two amino acid molecules

point mutations
gene mutations that involve changes in a single gene. They occur at a single point in the DNA sequence. They include: Substitutions. Insertions. Deletions

long chains of amino acids


a writers “first draft” pre-mRNA has bits and pieces cut out.

regions of DNA that have specific sequences. they are signals in the DNA molecule that show RNA polymerase exactly where to begin making RNA.

any of a class of nitrogenous organic compounds that consist of large molecules composed of one or more long chains of amino acids

ribonucleic acid

the sugar in RNA

ribosomal RNA
Forms an important part of both subunits of the ribosome.

rRNA and protein make up a ribosome. Ribosomes use the sequence of codons in mRNA to assemble amino acids into polypeptide chains in translation

nucleic acid that consists of long chains of nucleotides.

RNA polymerase
RNA Polymerase is the enzyme
responsible for transcription in the cell
• First, it opens up a specific portion of the
DNA to be copied
• Then, it uses a single strand of DNA as a
template for the RNA copy
• RNA polymerase is responsible for adding
single nucleotides to the template strand of

silent mutation
change in the base where amino acid stays the same

The RNA formed from Transcription is made up of two types of regions
-Introns and Exons
they differ depending on the
gene or characteristics we are looking for
– We cut out the introns leaving only the

start codon
AUG- methionine. initiation for protein synthesis

stop codon

one base is changes to a different base. They usually affect one amino acid, and sometimes have no effect at all.

segments of DNA serve as templates to produce complementary RNA molecules

transfer RNA
Carries amino acids to ribosome and matches them to the coded mRNA message.

The act of decoding the
mRNA message into a chain of amino
acids or a protein
It happens at the ribosomes where
they read and assemble the
amino acid chain

RNA contains this instead of thymine