Chapter 7 Microbial Genetics
the transmission of genetic material (DNA and RNA) from an organism to its offspring
DNA + protein
a sequence of DNA that codes for a particular trait
basic unit of heredity
also means location
genes with different information at the same location
a permanent alternation in DNA
refers to the genetic information contained in the DNA of the organism
refers to the specific characteristics displayed by the organism
linear sequence of nucleotides of DNA that form a functional unit of a chromosome or a plasmid
information in a specific gene, found at a particular place on the chromosome or plasmid
In what three major ways can the information in DNA be transferred?
1. DNA Replication
What are the reasons we copy/replicate DNA?
In this transferring of information in DNA, DNA produces more DNA
in this transferring of information in DNA one strand of each DNA molecule is half old and the olther is half new
governs strand assembly and proofreads
What do ribosomes make?
In this part of transferring information in DNA RNA is produced using DNA as a template
Refers transcription occurs in what?
ribosomal RNA (rRNA)
carries instructions to build proteins to the ribosomes (each three RNA bases specify a particular amino acid or a stop code)
messenger RNA (mRNA)
transfers needed amino acids from cytoplasm to ribosomes
trandfer RNA (tRNA)
Why do ribosomes need amino acids?
to build proteins
in this porption of transferring information within DNA ribosomes "read"messenger RNA and link the coded for amino acids together into proteins
Approximately what percentage of a bacterial cell's energy is used to produce proteins?
80 to 90
What two causes of mutations does your book list?
mutations that have no know cause
mutations caused by mutagens
tend to increase the mutation rate above the spontaneous rate
give two examples of known mutagens
something that can cause a mutation
What are the two tyoes of mutations?
1. Point Mutation
2. Frameshift Mutation
in this type of mutation a single base is replaced and it may or may not cause problems
in this type of mutation an insertion or deletion of one or more bases takes place and it always causes a problem
these are found in cured meat such as deli meats, hot dogs, and bacon
nitrates and nitrites
one of the first tests done on new products to see if there are mutations
The ames test uses what that can not make histidine
Why does the ames test use a certain strain of salmonella?
it uses a strain that can not make histidine amino acids so it can't make proteins
What is the end result of the ames test believed to be if the new product does contain mutagens
if salmonella makes histidine right away
removes an amino group (-NH2) from a nitrogenous base to point mutations
Bacteria have _______ as their genetic material
Which base is NOT found in DNA?
The first bacterium to have its genome completely sequenced was:
The process of reverse transcription creates:
DNA from RNA
During DNA repliction, DNA ploymerase adds nucleotides:
to the 3' end of the growing strand
During DNA replication, the new strand has a sequence ______ to the strand being copied
DNA replication is termed
The enzyme responsible for transcription is called:
In prokaryotes, transcription takes place in the:
Ribosomes are made of
RNA and protein
tRNA is responsible for transporting _______ to the ribosome
Each tRNA has a/an _______ that allows it to match up with the correct mRNA codon
The bond that is created between amino acids is called a _______ bond
Repressors are molecules that inhibit:
A phenotypoe refers to the ________of an organism
expressed physical characteristics
A mutation that results in a change in DNA sequence, but no change in the amino acid sequence of the protein, is termed ______ mutation
Which of the follwing can induce mutations?
The Ames Test is used to test whether or not:
a chemical is mutagenic