Studied by 11 peopleTranscription
Initiation-RNAp attaches to a promoter of DNA
Elongation-RNAp opens the DNA and reads the triplet code, makes mRNA with RNA nucleotides
Termination- Poly-A tail, and release of pre-mRNA from DNA
Prokaryotes need
no transcription factors and RNAp can bind straight to the primer
Eukaryotes have
factors and the TATA box to help it bind
5' cap and poly-A tail function to
help mRNA leave the nucleus, protect from degradation and attach ribosome to 5' end
Alternative splicing is
when a single gene can code for more than one protein
Eukaryotes have splicing in the
nucleus and ribosome
Prokaryotes have splicing in
cytoplasm
tRNA has an anticodon region which is
antiparallel to mRNA
Ribosomes are different
sizes
Prokaryotes--->
small (30's), large (40's)
Eukaryotes--->
small (40) large (60)
Translation
Initiation: small subunits binds to the mRNA and tRNA binds to start codon
Elongation: mRNA is moved through the ribosomes and codons are read
Termination: stop codon reaches the A site, the polypeptide chain is released
Operon parts
Promoter: RNA polymerase can attach
Operator: on/off switch
Gene: code for related enzyme in pathway
Repressible (on to off)
transcription is usually on, but can be repressed (stopped)
Inducible (off to on)
transcription is usually off, but can be induced (started)
Operation of inducible operon
When allolactose is present it will bind to the lac repressor and turn the lac repressor off, genes can now be transported
Morphogenisis
physical process that gives organisms their shape
Histone acetylation
adds acetyl groups to histones, which loosens up DNA
DNA methylation
adds methyl groups to DNA, chromatin condenses
Large
chromosomal change
small
nucleotide substitutions, insertion, or deletion
Point mutation
a change in a single nucleotide pair. This affects the activity of an enzyme because the AA can be changed or an unnecessary stop codon can make it ineffective and not function properly
transformation
uptaking of DNA from a nearby cell
Conjugation
cell to cell transfer of DNA
Transduction
viral transmission of genetic material
During gel electrophoresis DNA moves to the
end because DNA fragments are - charged
Seperate fragments in
gel by size
Function of PCR
make several copies of a DNA segment
Metastasis
the spread of cancer cells from the place where they first formed to another part in the body
Purines
doubles ring, A,G
Pyrimidines
single ring, CUT
A,T
2 hydrogen bonds
G,C
3 hydrogen bonds
Backbone
sugar-phosphate
Center
nucleotide pairing
5'
phosphate group
3'
hydroxyl group
Strands from semi-conservative
2 daughter molecules have 1 parental and 1 new strand
DNA polymerase 3 goes
3' to 5'
mRNA
Messenger, carries DNA in the nucleus to the ribosome
tRNA
transfer, carries a specific AA, allow information to be translated in a peptide chain
rRNA
helps form ribosomes and link AA
Note
Flashcard