Genetics

A complex of several ribosomes translating from the same mRNA

• Changes the amino acid it codes for;
• eg. Sickle cell anemia

• change in base of codon, does not change amino acid but is a new allele
• GCA > GCC, both Ala

• replaces codon with a stop codon
• shorter than it is suppose to be

5' to 3' direction

the enzyme that catalyzes transcription

DNA sequences near the beginning of a gene that signals RNA polymerase to begin transcription

Sequences in the RNA products that tells the RNA pol where to stop

• Rho dependent
• Rho independent
• Transcription

• Shine Dalgarno Sequence
• AGGAGG , purine rich
• tRNA carries formylmethionine
• translation in the cytoplasm ; tightly coupled

• binds to 5' cap
• imitator tRNA carries Methionine
• transcription and replication in nucleus
• translation in the cytoplasm

• some terminators involved
• recognized by a protein
• disengages the RNA pol

• does not involve a protein
• sequence mediated

• amino acid coding regions
• they contain expressed sequences found in both a genes DNA and in the mature mRNA

• amino acid non coding region
• they contain non intervening sequences found in the gene, not in mature mRNA

• primary =/= mRNA
• 5' cap
• 3' A tail
• splicing

• no postranscriptional processing
• primary = mRNA

• The restoration of a gene function by one mutation by cancelling the other in the same gene
• wrong making a right !

• sense strand
• coding strand
• + strand

• Lac Z - encodes for b galactosidase (break down lactose into galactose and glucose)
• Lac Y - encodes for permease (allow lactose into the cell)
• Lac A - encodes for transacetylase that adds an acetyl group to lactose

• one mRNA with 2 or more transcribed genes on it
• eg. lac operon

a unit of DNA composed of specific genes, plus a promoter and operator, which acts in unison to regulate the response of the structural genes to environmental changes

regulatory site that can be located far away from the core promoter or quite close

• initiation site ( +1 of transcription)
• TATA box (-30 position) approx 7 nucleotides
• CAAT box (-75-100 position)
• GC boxes

• TATA box binding proteins
• essential to the initation of transcription from all class II genes with a TATA box

TBP associated factors

• increase transcription by 100 folds
• has two important domains ;DNA binding domain and the transcription activation domain

bind to specific set of genes at sites known as silencers and slowing transcription

these "adaptor" molecules integrate signals from activators and maybe repressors

in response to injunction from activators, these factors position RNA pol at the beginning of transcription

• Multimeric proteins composed of identical subunits
• 2 subunit = homomers

• the movement of charged molecules in an electric field.  DNA in solution is weakly acidic(-ve charge)
• The larger the molecule, the slower it moves through the matrix

the process of using living cells to make many exact replicas of a fragment of foreign DNA

• plasmids
• YAC (Yeast artifical chromosomes)

the proportion of individuals in a population that are of a particular phenotype

the proportion of individuals in a population that are of a particular genotype

the proportion of all copies of a gene in a population that are of a given allele type

• effects the allele frequency
• unpredictable, chance fluctuation in allele frequency that have no effect on survival
• smaller the population, the greater effect of
• the drift

When two thymines are adjacent to one another in a DNA strand, the absorption of UV radiation can cause the formation of a covalent bond between them

purposeful matings

• easy to cross fertilze
• short growing season
• large number of offsprings

• Observable characteristics
• determined mostly by genotype
• commonly referred to as a trait

• genetic make up
• description of the genetic information carried by the individual

offspring always showed the same phenotype as the parent plants

theories that one parents contribute most to an offspring inherited features

• describes how alleles in a gene behave
• the two alleles for each trait separate during gamete formation, then unite at random, one from each parent, at fertilization

• multiple phenotypic effects caused by a single gene
• eg sickle cell anemia

a phenotype arising from the action of two or more genes ( polygenic) or from interactions between genes and the environment

9:7

9:3:4

12:3:1

most common traits are determined by more than one gene

2 or more genes can work in tandem, in the same biochemical pathway to produce a particular trait

nuclear division that results in 2 daughter cells each containing identical numbers of chromosomes to the parent cells clones

nuclear division that results in each egg and sperm containing 0.5 the number of chromosomes found in other cells (somatic)unique

3' OH to extend upon

• 5' to 3' polymerase activities
• 3' to 5' exonuclease activity ( proofreading)
• 5' to 3' exonuclease activity (removing primer)

the number of times a given gene is present in the genome

lie adjacent to each other , either in the same order or in reverse order

two or more copies of a region that are not adjacent to each other and may lie far apart on the same chromosome or different chromosome