Nucleotides Flashcards
How does DNA replication occur
Semi conservative replication
Enzyme Helicase breaks Hydrogen bonds between polynucelotide strands
Each strand acts as a template strand
Free floating nucleotides align with complementary bases on template strand and and Hydrogen Bonds reform between them
SUGAR PHOSPHATE BACKBONE FORMS- DNA POLYMERASE JOINS BACKBONE
1 new and 1 old strand
Whta bases are pyrimidines and purines
Purines - A G –> 2 RINGS
Pyrimidines –> T U C 1 RING
What is the defenition for a gene
Seequence of DNA Nucleotides that code for a polypeptide
How does a Genetic Code code for a protein
3 Bases/Codons code for a specific A.A
Sequence of bases determine sequence of a.a
What does it mean if a genetic code is degenerate
A.A coded for more than 1 base
What does it mean if a genetic code is universal
Triplet codes for all organisms
What structure does DNA form
Double - Helix –> two strands antiparallel so they twist
What is different about RNA?
Only 1 strand and no Hydrogen bond
Found in nucleus and cytoplasm
How is info on genes used to synthesis a protein
Synthesis –> DNA copied into mRNA molecule (transcription) and leaves nucleus through nuclear pores
complementary base pairing occurs
triplet code
base sequence determines a.a sequence
ribosome
trna brings a.a
What is the role of mRNA
To deliver genetic info from DNA from nucleus to ribosome
How does the structure of DNA allow for replicaiton
DNA is double stranded thus each strand can act as a template strand for the formation of a new strand and Hydrogen Bonds break for free nucleotides to align with their complementary bases on template strand for new Hydrogen Bonds to form betwene them. Purines ONLY ALIGN with Pyrmidine Bases
What does RNA Polymerase do
Copies DNA Sequence into RNA Sequence
Why may modifications to a gene cause it to be long lasting
As changes in tertiary structure cause tertiary structure to no longer become complementary to shape of active site on enzyme
What occurs during transcription and Translocation for nucleotides
Gene undergoes transcription in nucleus –> production of mRNA thus mRNA sent of of nucleus to ribosomes. Translation at ribosomes thus tRNA with specific a.a binds its anticodons onto codons on mRNA –> formation of peptide bonds between a.a
Describe what each step in extracting kwii does:
Crush to break cell wall
Add Detergent
Add Protease
Filter
Pour cold alcohol
Crush –> Breaks cell wall
Detergent –> Dissolves nuclear memb.
Protease –> Breaks down histone proteins
Filter –> Remove any solid
Cold alcohol –> Dna is insoluble thus floats up to the top
