Chapter 12: DNA and RNA and Protein Flashcards
what do eukaryotic gene structures contain?
promoter, coding region (exons and introns), and termination signal (terminator)
to be expressed as a gene, DNA must be
copied into mRNA
mRNA must be used to make protein
proteins are the workhorses of the cell
what is the central dogma?
DNA -> RNA -> protein
what is a promoter and where is it located?
region the controls when and where DNA is transcribed into RNA
it is located upstream (in front of) the coding region
what is the coding region?
part of the gene that is transcribed into RNA
in the coding region, mRNA is later transcribed into
Protein
what sites do coding regions contain?
start and stop sites for RNA synthesis
what are exons?
regions that code for amino acids
what are introns?
noncoding regions of DNA
what is the termination signal (terminator)?
sequence of DNA that tells the RNA polymerase to stop making RNA
what type of genes contain introns?
eukaryotic
prokaryotic does nto
what is monocistronic and what type of gene has it?
1 gene -> 1 polypeptide
eukaryotic and prokaryotic
what is polycistronic and what type of genes is it?
many genes arranged in an operon
only prokaryotic
what is DNA transcribed into?
rna
what is transcription?
enzyme?
location?
RNA synthesis
RNA polymerase
in nucleus in eukaryotes
what is the purpose of transcription?
to make RNA from DNA
process of RNA and protein synthesis in eukaryotes
what are the steps, what do the make, where??
transcription (makes pre-mRNA in nucleus)
RNA splicing (makes mRNA in nucleus)
translation (makes protein in cytoplasm)
process of RNA and protein synthesis in prokaryotes
what are the steps, what do the make, where??
transcription (makes mRNA in cytoplasm)
translation (makes proteins in cytoplasm)
how does transcription differ in prokaryotic and eukaryotic?
prokaryotic- makes mRNA in the cytoplasm
eukaryotic- makes pre-mRNA in the nucleus
is prokaryotic or eukaryotic simpler? why!
prokaryotic
no introns or nucleus
what are the 3 types of RNA?
mRNA (messenger) - codes for AA in protein
rRNA (ribosomal) - structural part of the ribosome
tRNA (transfer) - brings AA to the ribosome during protein synthesis
how is rRNA folded up?
into a complicated secondary structure
brings the amino acid to the ribosome during protein synthesis
tRNA
what does the end of the tRNA react with?
mRNA
what are the steps in transcription in prokaryotes?
initiation, elongation, termination
what is step 1 in transcription: initiation?
sigma factor (a transcription factor)binds conserved DNA sequences in the promoter
RNA polymerase binds to sigma factor
region of DNA and RNA polymerase unwinds
what is a factor?
protein
what is the second step of transcription: elongation
sigma factor binds to conserved DNA sequences found in the prometer
RNA polymerase binds to sigma factor
sigma factor is released from DNA
RNA polymerase begins making RNA, using DNA as a template
what would happen to the RNA polymerase if it didn’t have the sigma factor?
it would bind randomly
what is the template strand?
strand of DNA copied into RNA
what is the coding strand?
strand of FNA that has the same sequence as the RNA
what direction is RNA always made in?
dna copied?
5-3
3-5
how is RNA made from DNA?
by adding the complementary bases into the new RNA
bases in RNA are ____ to bases in DNA
complementary
what is termination?
when RNA polymerase reaches the terminator it stops making RNA and falls off
the newly made mRNA is released from the DNA
what is RNA splicing?
removes introns and makes nature mRNA
what is made in transcription in RNA synthesis?
makes pre-mRNA (exons and introns