What are the primary sources for heritable information
DNA and RNA
How is genetic information stored and carried through generations
DNA and RNA molecules
What type of chromosomes do prokaryotic organisms have vs eukaryotic
prokaryotic- circular
eukaryotic- linear multiples
What are plasmids
small extra-chromosomal double-stranded circular DNA molecules
What are the nucleotide base pairings
adenine-thymine/uracil
cytosine-guanine
What nucleotides are purines and what is their structure vs pyrimidines
purines- adenine and guanine, double-ring structure
pyrimidines- cytosine, thymine, uracil, single ring structure
Which way is DNA synthesized
5’ to 3’
Replication is what type of process, what does this mean
semiconservative, one strand of DNA serves as the template for the new complementary strand
What unwinds the DNA strand
helicase
What do topoisomerase do
relae supercoiling in front of replication fork
What does the DNA polymerase need to activate
RNA primers
What does the DNA polymerase do
synthesizes new DNA stand continuously on the leading strand and discontinuously on the lagging strand
What joins the lagging strand fragments
ligase
What do mRNA molecules do
carry information from DNA to ribosomes
How is the peptide sequence formed
tRNA binds to specific amino acids with anti-codon sequences on mRNA
What is rRNA
functional building clocks of ribosomes
What is the flow from genetic material to protien
genetic information in DNA to base sequences in mRNA, to sequences of amino acids for protein folding
What can the template DNA strand also be called
noncoding strand, minus strand, antisense strand
Which direction does the RNA polymerase synthesize mRNA
5’ to 3’ reading DNA 3’ to 5’
What are the eukaryotic mRNA modifications
addition of polt-A tail, addition of GTP cap, excision of introns and splicing/retention of exons
What are the translation sequential steps
initiation, elongation, termination
What are the salient fetures of translation
initiation with rRNA interaction with mRNA, mRNA is read in triplets called codons, each codon codes a specific amino acid, tRNA brings the correct amino acid to the correct codon, amino acids are transferred into grouping polypeptide chain, the process continues until stop codon releasing polypeptide chain
How does viral RNA incorporate into host DNA
reverse transcriptase
What are regulatory sequences
stretches of DNA that interact with regulatory proteins to control transcription
How do epigenetic changes affect gene expression
through reversible modification of DNA or histones
How are groups of genes coordinately regulated in prokaryotes and eukaryotes
prokaryotes- operons transcribed into single mRNA (i.e lac operon)
eukaryotes- same transcription factor influence
What are promoters
DNA sequences upstream of the transcription site
How do negative regulatory molecules work
inhibit gene expression by binding DNA and blocking transcription
What results from gene regulation
differential gene expression and influences cell products and function
How are new phenotypes created
disruptions in genes and gene products
How do mutations occur
alterations in DNA sequence resulting in protein production changes (i.e too much, not enough, damaged protein)
What is electrophoresis
separates molecules according to size and charge
What is polymerase chain reaction (PCR)
DNA fragments are amplified
What is bacterial transformation
introduction of DNA into bacterial cells