RNA & Transcription Flashcards
Define Polyribosome..?
Multiple ribosomes using the same blueprint simultaneously.
Types of RNA are..
mRNA - Messenger RNA ((5% of cellular RNA))
tRNA - Transfer RNA ((21% of cellular RNA))
rRNA - Ribosomal RNA ((72% of cellular RNA))
Name the 3 Transcription parts..
- Initiation
- Elongation
- Termination
Define Initiation
Proteins that recognize specific DNA sequences & Initiate transcription.
allow cells to pick out which genes will be transcripted
What do Enhancers do?
Enhance or promote the transcription.
What do Inhibitors do?
Block transcription
What is RNA Polymerase?
Similar to DNA Polymerase but requires less help
NO primase, liquase, helicase, gyrase.
What is Elongation?
RNA Polymerase create an RNA transcript only uses 1 strand of
DNA -> coding strand.
Name the two types of Protein Termination
- Protein Dependent
2. Protein Independent
Protein Dependent is..
Rho protein terminator.
Binds to DNA & physically stops polymerase. “road block”
Protein Independant
RNA transcription itself stops transcription
folds up & pulls itself free of polymerase
RNA Processing
Bacteria, termination is the end.
often times ribosomes begin translation while the mRNA is still being made.
What are Operons ?
Groups of genes transcribed as one giant product, then cut into individual pieces.
What are Introns?
Sequences that don’t belong in the protein.
What are Exons?
Sequences that do belong in the protein.
After processing the mRNA is shuttled where?
To the Cytoplasm
What is a stop codon?
3 possible codon
no amino acid associated w/ them
terminates translation
What is a Anti-Codon?
Part of the tRNA that recognizes the codon of the mRNA
What is the A site?
tRNA cells enter.
What is the P site
Amino acids link together
What is the E site
Empty tRNA’s are spit out
What happens in termination?
stop codon brings an enzyme called a release factor in
free the protein
What are the two types of mutations?
- Spontaneous Mutations
- Occur randomly - Induced Mutations
- Environmentally factors induce.
What are Mutagens?
Known to chemically alter nucleotides
What are Carcinogens?
Mutagens that typically result in cancer
What are Teratogens
Mutagenic to developing organisms
