Theme 2a Flashcards
What is the central dogma of molecular biology
The flow of information from DNA to protein (converting genotype to phenotype)
Where do transcription and translation occur in prokaryotes
Both in the cytoplasm
Where do transcription and translation occur in eukaryotes
Transcription is in the nucleus and translation is in the cytoplasm
How does mutating a gene that is encoding an enzyme disable normal synthesis nutrients properly
Causes a block in the metabolic pathway
What did Beadle and Tatum hypothesize about the process of making an essential nutrient
-genes that code for function at each step of a biochemical pathway are needed
-if one of the genes is mutated it causes a build up of the molecule that came before it (if gene B synthesized enzyme B which catalyze the reaction from A to B there would be a build up of A)
What is the isolation of arginine (an essential amino acid) auxotrophic mutants used for
-to determine which mutants are unable to grow without arginine
-these mutants have a defective gene for an enzyme needed to synthesize an intermediate product to produce arginine
What is a gene
When information flow occurs on chromosomes
What types of RNA do genes encode for
Coding RNA (mRNA): codes for proteins/polypeptides
Noncoding RNA (tRNA, rRNA, snRNA, microRNA): doesn’t code for proteins
What is a codon
A three letter code of RNA bases that codes for amino acids
On chromosomal maps where are the genes shown
On the coding strand
Top vs bottom depends on the genes
What is reverse transcription and in what does it occur
RNA to DNA
Occurs in viruses with RNA genomes
Why does reverse transcription occur
Viral RNA needs to be converted into viral DNA to integrate into the hosts genome
What are integrase and protease enzymes (viruses)
Integrase: facilities insertion of viral DNA into host genome by cutting host DNA
Protease: breaks up polyprotein chains and allows for them to mature and make up the final varions to infect other cells
Why is COVID so infectious
-no lysogenic (dormant) cycle, only lytic
Did DNA or RNA come first
RNA because it can store genetic information as well as catalyze reactions which DNA cannot
