Ch 9 Genetics & Flow of Genetic Information
Genotype
(sum of all gene types) DNA sequences An organisms distinctive genetic makeup
Transduction
-Bacteriophage infect host cells -Serve as the carrier of DNA from a donor cell to a recipient cell
Conjugation
-Transfer of plasmid DNA from a F+ (donor) cell to a F- cell -An F+ bacterium possesses a pilus that attaches to the recipient cell and creates pore for transfer
rRNA
-Transports the DNA master code to the ribosome -Single strands of RNA transcribed from DNA templates -RNA polymerase performs the synthesis -Assembled in the 5' to 3' direction
Codons
-Triplets of nucleotides that specify aa's -Multiple codes for one amino acid -20 aa's, start codon, stop codon
Primase
Adds RNA primers
In protein synthesis of Eukaryotic cells, mRNA molecules:
Contain sequences called introns that must be removed
RNA
Contains ribose as the sugar Uracil instead of thymine The nucleic acid responsible for carrying out the hereditary program transmitted by an organisms DNA.
Transcription
DNA is read or 'transcribed' into mRNA Synthesis of RNA molecules
DNA Polymerase
DNA polymerase I -Removing primer, closing gaps, repairing mismatches DNA polymerase III -Adding bases to the new DNA chain; proofreading the chain for mistakes
Promoters
DNA sequences that bind a protein called the sigma factor *TATA box (TATAAT)
Transcription Unit
DNA that encodes RNA (and the protein) sequence
Ligase
Joins DNA molecules together
Procaryotic
Single, circular molecules
DNA structure
Sugar = 'deoxyribose' (a ribose missing an oxygen) Phosphate molecule Four types of nucleotides -A-Adenine -T-Thymine -G-Guanine -C-Cytosine
Replication
Synthesis of new DNA molecules
DNA replication
The DNA strands are each copied (replicated) just prior to cell division so each new cell will have it's own DNA double-helix.
Replication Fork
The Y-shaped point on a replicating DNA molecule where the DNA polymerase is synthesizing new strands of DNA.
Synthesis of Protein requires:
mRNA, tRNA, and ribosomes
tRNA
-Brings amino acids to ribosome during translation -Participates in translation, carries amino acids to ribosomes -Complimentary sequences form hairpin stem-loops -Amino acid attachment site and the 'anticodon'
rRNA
-Forms the major part ribosome -participates protein synthesis -consists of 2 subunits (large and small) -a subunit is composed of rRNA and protein -performs translation reaction
Transformation
-Nonspecific acceptance of free plasmid DNA by the cell -DNA can be inserted into the chromosome -Competent cells readily accept DNA at a higher frequency
Chromosome
A discrete cellular structure composed of a neatly packaged DNA molecule. (DNA + Proteins)
Sigma
Allows the RNA polymerase bind and promotes synthesis of RNA
RNA polymerase
Enzyme that performs transcription 'makes polymers of RNA'
Phenotype
Expression of the genotypes in the form of proteins.
Griffith Experiment
First experiment suggesting that bacteria are capable of transferring genetic information through a process known as transformation.
Ribosomes
Form peptide bonds
Eucaryotic
Linear, numerous, numbered
Lagging Strand
Multiple (okazaki) fragments are synthesized and ligated to form one continuous strand.
Introns
One to several intervening sequences of bases located along the gene
In cells the synthesis of new DNA molecules requires:
Primers, nucleotides, and DNA polymerase
Okazaki Fragments
Producing short fragments of DNA 5--3
Translation
RNA is read or 'translated' into amino acids (proteins) DNA--RNA--Amino Acids (proteins) Synthesis of Protein
Protein
RNA molecule
Gyrase
Rewinds (supercoils) the DNA
The Stop Codon UGA
Signals the halt to addition of new amino acids
Leading Strand Synthesis
The newly forming 3' DNA strand that is replicated in a continuous fashion without segments.
Transformation
The process by which bacteria absorbs free plasmid DNA
The Central Dogma
Transcription Translation
Codons
Triplets of nucleotides that encode one amino acid
Helicase
Unwinds strands Unzipping the DNA helix
Mutations of DNA
can be detrimental or beneficial
Genome
the sum total of genetic material of a organism
