The Central Dogma 2A Flashcards
Central Dogma of Molecular Biology (2)
Universal information flow from DNA-Proteins in-order to convert genotype to phenotype
(info flow from genes to protein)
Talk about transcription and translation in prokaryotes (2)
they both occur in cytoplasm and both processes can occur simultaneusly
translation occur even before transcription is done
Talk about transcription and translation in eukaryotes
Transcription and processing of the precursor Mrna molecules occur in the nucleus and translation occurs in the cytoplasm
one gene one enzyme hypothesis
proposed by George Wells Beadle and and Edward Tatum in 1941, is the theory that each gene directly produces a single enzyme, which consequently affects an individual step in a metabolic pathway.
correct btw
Garrod
studied a hereditary disease called Alkaptonuria where patients inherit a mutated gene coding for a defective enzyme resulting in abnormal cellular metabolism (black pee)
mutating a gene encoding an enzyme would (3)
cause a block in the metabolic pathway and the organism can no longer synthesize the needed nutrient (auxotroph)
gene no longer work
Genes encode for 2 types of rna
coding rna- codes for protein/polypeptide
noncoding rna- trna, rna, sırna
information flow graphs arrow
arrow head=3’ end of gene
information is contained in ___ nucleotide bases in dna or rna
4
dna 3 letter code
triplet
rna 3 letter code
codon
genetic code is
*Not what it is
universal, same code in prokaryotes, eukaryotes and viruses
RNA synthesis (3)
only produced from one of the DNA strand (template)
the other dna strand is the non template strand or coding strand.
The template strand is always read from 3’-5’ direction by RNA polymerase/ mRNA is synthesized in the 5’-3’ direction
RNA polymerase can only
add on the hydroxyl end
which strand is similar to the RNA molecule?
the coding strand (one not being read)
RNA is the same to the - end of the template dna
5’-3’
translation and transcription occur in the
*not location
….orientation
same direction
On chromosomal maps, genes are shown on the
coding strand
integrase +end product (2)
cut open the DNA of host cell and helps integrate the dna of virus into dna of host cell
**combination of host cell and virus DNA
reverse transcription steps: (7)
- Fusion of the 2 membrane
- rapidly makes a much more nuclease-resistant double-stranded DNA copy of the RNA template that later integrates to form the proviral DNA by using host nucleotides. Happens twice so its double stranded
- integrate carries viral dna thru a nucleus pore cuts open host cell dna and combines virus dna with host (what establishes life long infection)
- each time host cell transcribe, viral dna will be produced
- Viral DNA will be translated by the ribosome in the host cell
- Viral proteins that the cell create will assemble into immature viruses containing the protein stuff and rna strand it needs made by the host ribosomes
- Buds off with the virus’s original surface protein attached since its still present on the cell surface in step 1 when the two mended
- Protease cuts the proteins instead the new formed and detached virus to form a mature virus
Reverse transcriptase (2)
convert RNA sequences to cDNA sequences that are capable of inserting into different areas of the genome with host nucleotides
makes a lot of error as they are not accurate
Explain why scientists think RNA came first: (4)
RNA can act like an enzyme to self edit their own genetic code.
Single stranded RNA is rather unstable and can easily be damaged by enzymes. It make sense to have evolved into a more stable DNA.
Likely RNA is also able to store genetic info
it can also catalyze reactions
