Omg literally goonna kms I hate bio SM UGh Flashcards
miRna
Basically binds to mRna to inhibit translation.
Different ways phenotypes can change
Phosphorylation: Depend
Histone Acetylation: Expresses it more involves the addition of an acetyl group to the histones. loosens chromatis
Histone Methylation: . Adds a methyl group to histone. can either activate or repress gene expression. depends on which amino acid is modified
After gene translation, when the protein folds and stuff.
#NotMutation!
DNA helicase
An enzyme that unzips the strands of DNA
Breaks through the hydrogen bonds
DNA polymerase
The builder
Replicate DNA molecules by building a new strand of DNA
Builds the new strand in the 5 to 3 direction meaning it moves along the 3 to 5 DNA strand.
Primase
The initializer
Primase makes the primer so DNA polymerase can know where to go to start working
Primers: short, single-stranded nucleic acid sequences, typically RNA, that provide a starting point for DNA
Ligase
Glues
Origin
Where DNA starts
DNA Replication steps
- Origin
- Helicase comes in and unzips everything
- Primase comes in and makes primers on both strands
- DNA polymerase
Topoisomerase
Keeps the strand from super coiling
Antiparallel
Run in different directions
5 to 3 prime
3 to 5 prime
Leading strand vs lagging strand
Leading strand is the one that builds continuously in the 5 to 3 prime direction by the DNA polymerase
Lagging strand: Fragments. Discontinuous
Okazaki Fragments
Fragments that form from the lagging strand
Ligase seals them together
Semi conservative
BC both the copies each contain one old original strand and one newly made one
Errors
DNA polymerase can proof read so it makes less mistakes.
Histones
where eukaryotic DNa is bound to structures called nucleosomes
nucleosomes
Replication fork
A y shaped structure formed during DNA replication where the DNA helix is unwound and sperated
telomeres
And thus the end of the DNA remains single stranded. No polymerase enzyme can add nucleotides to that region as they are direction specific.
If the condition prevails in each cycle of replication some part of DNA will be lost.
To avoid this lose every biological living system has an ribozyme(enzyme containing RNA sequence in it) TELOMERASE.
This establishes complementary hydrogen bonds with the SS DNA sequence and the polymerase part of that enzyme adds new nucleotides and prevents from shortening of DNA.
Transcription
Taking a gene of Dna and turning it into mRNA
Translation
The process of taking mRNA and creating a protein out of it.
mRNA vs DNA
Much shorter than DNA
single strand
mRNA is a temporary RNA version of a DNA recipe that gets sent to the ribosome
Transcription steps
- Takes place in nucleus
- RNA polymerase connects complimentary RNA bases to the DNA.. These RNA bases are bonded together to form a single strand of RNA
Initiation: Unwind and unzip; starts at the promoter.
Elongation:
Termination: when the RNA finishes adding on nucleotides it reaches the termination sequence from the DNA template,
Translation Steps
- rRNA (RIBOSome) the mRNA goes to the ribosome
mRNA attaches to the ribosome and waits for the appropriate anticodons to come - Ribosome will build the protein
- tRNA comes in and carries an amino acid (the monomer for a protein) all tRNA are looking for complimentary bases
Initiation: Ribosomes have 3 building sites A P E
ELongation: Addition of amino acids
Termination: The process is ended by stop codons
rRNA
Ribosomal RNA
Made up in the nucleus
tRNA
transfer RNA
it carries amino acids to the ribosome
responsible for bringing the appropriate into place at the appropriate time by matching anti codons to codons
Splicing
After transcription is complete the freshly transcribed RNA contains both coding and noncoding regions .
Exons stay in (coding regions)
Introns removed
Poly A tail and GTP cap are added to the 3 and t end respectively to reduce degradation as it moves out of the nucleuss to the ribosome
Codon
Three nucleotides
Transcription Factors
A group of molecules that can either encourage or inhibit transcription from happening.
- often done by either making it easier or more difficult for RNA polymerase to attach
- the genes that are expressed can lead to different types of gene expression which leads to different phenotypes
Epigenetic CHanges
A modification of GENE expression that does not involve changes to the DNA sequence itself.
Operons
A cluster of genes found in bacteria
Inducible: Off and needs to be turned on
Repressible: On and needs to be turned off by corepressor s
Operator in operons
where the repressor binds
Regulatory gene in operons
Codes for a regulatory proteins; repressor
if the repressor binds the gene wont be able to transcript
in inducible ones, usually something binds to the repressor for it to fall off allowing transcription
Mutation effects after point substitution
nonsense: Causes original to become a stop
Missense: causes original codon to alter into another one
Silent: nothing happens
Transduction
Bacteria receives new genetic information from virus
Transformation
The uptake of DNA from the environment
Conjugation
Cell to cell transfer of DNA
Transportation
Movements of DNA segments within and between DNA molecules
