DNA Test Flashcards
Explain the steps in Transcription
Initiation: The double helix DNA get unwound and strands attach to the promoter. Elongation: DNA moves in the 3’ to 5’ so a complementy rna strand will be in the 5’ to 3’ direction. Termenation: once polymerase reaches a certain point in the code it will reach a stop and the transcription process will end.
Explain the steps in translation
The MRNA will leave the nucleus and enter the cytoplasm to reach the ribosomes. In the ribosomes TRNA will assign the correct amino acid to the correct codon so in the end a protein can be made.
Steps in DNA replication
Helicase: Helicase will enter and split the DNA by breaking the hydrogen bonds. SSB’s bind to the separated strains of DNA to not allow them to reconnect. Primase is an enzyme that creates a primer to be put on end of each strand so DNA polymerase will know where to add nucleotides. Polymerase 3 will begin adding nucleotides to the leading strand continually. The lagging strand will be made in short segments called Okazaki fragments. Polymerase 1 will then come in and remove the primers and replace it with DNA. Ligase will then come in and connect the Okazaki fragments. The new DNA is then proofread and if all is well it will be done replication. DNA gyrase relives tension from DNA unwinding.
Explain protein synthesis
Transcription= DNA to MRNA Translation=MRNA to protien
Transcription takes place in the nucleus and translation takes place in the ribosomes. Protein synthesis is done to turn DNA all the way into useful protiens we can use.
Introns vs extrons
Introns carry junk info that needs to be cut out and extrons carry useful information in mrna
What direction is the leading strand continusly syntheised
The 5’ to 3’ direction
In the sugar phosphate backbone what is at the end of 3’ and end of 5’
Sugar and hydroxyl group 3’ and 5’ is phosphate group
What is a enhancer
It can inhibit or stimulate the rate of transcription
What is a activator
determines what proteins will be expressed
What is a genetic switch
It controls the expression of genes
What connects the sugar phosphate backbone
phosphodiester bonds
What are purines
Double ring structure like adenine and guanine
what are pyrimindes
single ring structure like thymine and cytosine
Polypeptide
Chain of amino acids
Primary MRNA
The exact complementary strand of the DNA strand
