exam 3 (chapter 17, 18) Flashcards
DNA>RNA (nucleotide>nucleotide)
Transcription
RNA>protein (nucleotide>amino acid)
Translation
The process by which we turn DNA into phenotypes (what we physically look like)
Gene Expression
The one DNA molecule transcribed into RNA
Template Strand
Pries two strands of DNA apart and joins together RNA nucleotides complementary to the DNA template
- Assembles RNA nucleotides in the 5’>3’ direction
- Does not need a primer
RNA Polymerase
DNA sequence where RNA polymerase attaches
- Indicates which DNA strand is to be copied
- Not transcribed
Promoter
DNA sequence that signals the end of transcription, is transcribed
Termination
- Only the area of one gene (or a few genes) is copied
- Highly selective
- **Only the genes currently needed are copied
- No primer needed
Transcription
The entire DNA molecule is copied, always essentially the same, requires a primer
DNA Replication
Produces mRNA, transcription and translation take place simultaneously
Prokaryotic Transcription
Produce pre-mRNA, it is extensively modified to become mRNA before leaving the nucleus
Eukaryotic Transcription
mRNA removed before translation
Introns
Remaining mRNA to be used during translation
Exons
The process of removing introns in the nucleus
RNA Splicing
Consists of snRNP subunits; binds to pre-mRNA at multiple sites along the intron, snip the intron, and join the exons
Spliceosomes
Small nuclear ribonucleoproteins; composed of snRNA and proteins, recognize introns
snRNPs
A ribozyme, a catalyst that is a RNA molecule, not an enzyme (protein)
snRNA
Messenger RNA; carries the codon from the DNA to the ribosome
mRNA
Transfer RNA; brings amino acids to the ribosomes
tRNA
Ribosomal RNA; component of ribosome, most abundant RNA
rRNA
Structural components of spliceosomes when removing introns from eukaryotic pre-mRNA
sRNA
The messenger RNA nucleotide triplets
Codon
Consists of rRNA and proteins organized into 2 subunits
Ribosome
Contains a mRNA binding site
Small Subunit
Lines up the tRNA
Large Subunit
Holds the tRNA carrying the growing polypeptide chain
P-site (peptide tRNA)
Holds the tRNA carrying the next amino acid
A-site (aminoacyl tRNA)
Discharges tRNA
E-site (exit site)
Change in a single nucleotide (1 letter changed)
example: sickle cell disease
Point Mutation