Ch. 9 Microbial Genetics
gene
A specific segment of DNA that contains the necessary code to make a protein or RNA molecule is a?
Gene
what is the site on the chromosome that provides information for a certain cell to function?
mRNA
what is the transcript that is used in transcription called?
genetic material flows from DNA to RNA with RNA being "junk". We now know that RNA can be used to regulate gene function.
what was the central dogma and how has it changed?
Mutations that lead to cell dysfunction or death
What are lethal mutations?
Any change in the code that leads to placement of a different amino acids
What are missense mutations?
Produce neither adverse nor helpful changes
What are neutral mutations?
Small mutations that affect only a single base on a gene that involve addition, deletion, or substitution of single bases.
What are point mutations?
Conjugation: attachment of two related species and the formation of a bridge that transports DNA. Transformation: the transfer of DNA that requires no special vehicle Transduction: DNA transfer is mediated through the action of a bacterial virus
What are the three modes of transferring DNA? Define them.
one side of the helix runs in the opposite direction of the other. One from a 5' to 3', the second from a 3' to 5'.
What is antiparallel alignment?
recombinant
What is any organism that contains and expresses genes that originated in another organism?
a copy of a structural gene or genes
What is mRNA?
Phenotype
What is the expression of an organisms traits called?
Transcription; RNA polymerase
What is the process by which DNA is converted into RNA? What enzyme is instrumental in this process?
Start codon: AUG Stop codons: UAA, UAG, or UGA
What is the start codon? what are the three stop codons?
Geneome
What is the sum total of all genetic information in an organism?
RNA into protein
What is translation?
One or more bases are inserted into or deleted from a newly synthesized DNA strand. This alters the reading frame of the mRNA. - Nearly always result in a nonfunctional protein - Every amino acid after the mutation is different from what is coded for in the original DNA - Insertion of bases in multiples of three does not disturb the reading frame
What occurs with frameshift mutations?
Changes a normal codon into a stop codon that does not code for amino acid
What occurs with nonsense mutations?
Alters a base, but does not change the amino acid and has no effect. The redundancy of the code assures that certain amino acids will not be altered by a change in the third base of the codon
What occurs with silent mutations?
PROG Promotor Regulator Operator Genes
What the parts of an operon, and the function of each? *watch bozeman science video over operon
Genotype
What the sum all all genes that constitutes an organisms genetic makeup?
DNA released from killed cells can be acquired by a live cell. The recipient is transformed from a nonvirulent to a virulent one.
What where the results of Griffith's transformation experiment?
In most eukaryotic genes, coding regions (exons) are interrupted by noncoding regions (introns).
Where are introns and exons found? what do they do?
Transcription occurs in the nucleous Translation occurs in the cytoplasm on the ribosomes
Where does transcription occur in eukaryotic cells? what about translation
Inducible operons are turned on by the substrate of the enzyme. repressibe are turned off by the product synthesized by the enzyme.
differentiate between repressible and inducible operons.
DNA polymerase adds new nucleotides towards from the replication fork for the leading strand in 5' to 3' direction. DNA polymerase adds new nucleotides away from the replication fork for the lagging strand in a 3' to 5' direction
in what direction does DNA polymerase adds new nucleotides in the for the leading strand, what about the lagging, in regards to the replication fork?
a sequence of three nucleotides that together form a unit of genetic code in a DNA or RNA molecule An anticodon is a three-base sequence on tRNA. It matches the codon
Compare codon to anticodon.
semi-conservative
DNA replication is described as conservative or semi-conservative?
A nucleotide; Phosphate, deoxyribose and a nitrogenous base; ATGC
Define the structure of DNA: What is the most basic unit? What do these units consist of? what do these subunits consist of?
Ribose, phosphate and nitrogenous base AUGC
Define the structure of RNA:
leading; lagging
During DNA replication, the ____ strand is synthesized continuously while the____ strand is synthesized in a series of short fragments called Okazaki fragments.
short segments of DNA synthesized in a 5" to 3" direction, which are later sealed together to form a 3' to 5' direction
what are okazaki fragments?
DNA consist of a deoxyribose sugar instead of a ribose and Adenine binds to Thymine instead of Uracil
what are the main differences in DNA versus RNA
RNA polymerase
what enzyme does transcription most heavily rely on?
DNA polymerase III
what enzyme synthesis a new daughter cell using the parent as a template?
a rapid screening test that scans for chemicals with carcinogenic potential.
what is Ames Test?
groups of 3 mRNA nucleotides.
what is a codon?
an operon
what is a group of genes that is under the control of a singe operator site?
the new strand of DNA that must be synthesized in short segments and later sealed in a 3' to 5' direction?
what is a lagging strand?
the strand of new DNA that is synthesized in a continuous manner in the 5' to 3' direction
what is a leading strand?
a primer
what is a length of RNA that is inserted initially during replication before being replaced by DNA?
each daughter molecule will be identical to the parent in composition, but neither is completely new
what is semi-conservative replication?
replication forks, 2
what is the place where DNA strands are unwound and replication takes place? How many?
redundancy
what is the property of several codons representing a single amino acid called?
