RNA, Transcription, and Translation Notes - Biology
what are the differences between DNA and RNA?
- DNA contains the sugar deoxyribose, RNA contains the sugar ribose - DNA is double stranded, RNA is single stranded - DNA contains the N-base Thymine, RNA never does; it contains he N-base Uracil
what does the RNA polymerase do?
-it unwinds DNA -makes a mRNA strand based on the sequence in DNA
when mRNA is done with its job it either....
-makes another protein -reused in ribosome -no longer needed -recycled/broken down
when tRNA is done with its job it is either.....
-reused -floats free in the cytoplasm -brings same amino acid back to translation
when rRNA is done with its job it either....
-ribosome is reused -looks for new mRNA strand
when a protein is done...
-used by an organism ex. makes hair, fingernails, enzymes grow
how many genes are copied in transcription?
1 gene
mRNA nucleotides order determines the order of the _______ determines what ___________
1.amino acids 2.type of protein
how many different types of tRNA molecules are there?
20 (one for each amino acid)
what is the start codon?
AUG
where is mRNA made from?
DNA in transcription
what is the purpose of transcription?
DNA strand provides a template for making a complementary mRNA.
what is the enzyme that will do most of the work in transcription?
RNA polymerase
in transcription, instead of T's...
U's are used instead
what are the stop codons?
UGA, UAG, UAA
what is transfer RNA?
a coiled, clover-shaped molecule that has one of 20 different amino acids attached to it.
messenger RNA
a single stranded copy of a gene that codes for a protein
what is in the other end of the tRNA molecule?
an amino acid
what is the purpose of mRNA?
it allows the information encoded in DNA to leave the nucleus.
when is tRNA used?
it is used in translation-using mRNA to make proteins
what is an anticodon site?
it matches to the codon of mRNA
what is the purpose of translation?
mRNA is used to make an amino acid sequence (protein!)
what are exons?
mRNA that codes for proteins and will leave the nucleus
do stop codons have an amino acid?
no, but they stop translation
where are the introns located?
nucleus
in transcription, how many genes are copied into mRNA?
one
how many amino acids is a codon specific for?
one amino acid
what happens at the P site?
tRNA's amino acid joins with the growing amino acid chain through peptide bonds
what happens at the A site?
tRNA's anticodon matches to mRNA's codon
what is ribosome RNA?
the most abundant form of RNA. the ribosomes themselves are made of rRNA
where does transcription take place?
the nucleus
what is splicing?
the process of removing introns and rejoining the cut end.
where does tRNA bring the amino acid?
the ribosomes
where does translation take place?
the ribosomes.
what do introns do?
they do not code for proteins and are removed before the mRNA leaves the nucleus
what are codons?
three-base nucleotide sequence on the mRNA
what are the two steps in proteins synthesis?
transcription and translation
when does translation take place?
when the rRNA assembles the proteins.
when does translation stop?
when the ribosome reaches the stop codon.
