Term
What must happen to proteins before it is released from the ribosome |
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Definition
It must fold upon itself to achieve its biologically achieve tertiary conformation Posttranslational modifications may be necessary - starting amino acids cut off - cofactors added - join with other proteins to form quaternary levels of structures |
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Term
Processing gene information in prokaryotes? |
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Definition
- mRNA can assiocate with ribosomes in the cytoplasm as the mRNA is being formed - translation of mRNA into proteins can begin before transcription is complete |
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Term
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Definition
individual mRNA molecules often contain transcripts for several genes. By placing genes with similar functions on the same mRNA, bacteria coordinate the synthesis of these proteins. These clustered genes are referred to as operons. |
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Term
Eukaryotic mRNA's code for how many proteins? |
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Definition
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Term
Can eukaryotic transcription and translation occur at the same time? |
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Definition
nope because the DNA is in the nucleus, it must occur in different compartments |
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Term
What do eukaryotic DNA often have? |
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Definition
Introns! these must be removed before translation |
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Term
What make up split genes? |
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Definition
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Term
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Definition
sequences of bases that do not code for protein |
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Term
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Definition
coding regions that will be translated into protein |
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Term
What percent of DNA do introns make up? |
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Definition
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Term
How is the nucleic acid arranged in virus |
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Definition
usually linear but can also be circular |
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Term
How is the genome arranged in viruses? |
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Definition
usually a single molecules, but can also be segmented into several peices |
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Term
Info about animal viruses |
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Definition
-viral nucleic acid penetrates the cell -nucleic acid penetrates the cell - the virus instructs the host's machinery to synthesize large numbers of new virus particles - viral mRNA is translated into viral proteins on host cell ribosomes using host tRNA |
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Term
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Definition
the operons is turned on by the substrate of the enzyme for which the structural genes code (positive feedback) |
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Term
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Definition
contain genes coding for anabolic enzymes; several genes in a series are turned off by the product synthesized by the enzyme (negative feedback) |
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Term
An inducible operon is kept "off" by...? |
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Definition
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Term
What does the substrate act as for an incucible operon? |
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Definition
an inducer! it blocks the action of the repressor, allowing the operon to be "on" |
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Term
Example of Incucible Operon |
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Definition
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Term
What is the regulator in Lac Opreon |
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Definition
a gene that codes for a protein capable of repressing the operon, which is the repressor |
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Term
What are the control locus feature of Lac operon |
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Definition
Promoter: recognized by RNA polymerase Operator: a sequence that acts as an on/off switch for transcription |
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Term
Structural Locus feature in Lac opreon |
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Definition
three genes each coding for a different enzyme needed to catabolize lactose |
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Term
Co-repressor in repressible operon |
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Definition
excess nutrient serves as this, it is needed to block the action of the operon |
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Term
Example of repressible operon |
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Definition
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Term
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Definition
through this, the bacterium can induce or repress the expression of a set of genes and change its phenotype -turn on and off particular genes |
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Term
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Definition
a change in nucleotide sequence (ATCG) |
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Term
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Definition
a microorganism that exhibits a natural, non-mutated characteristic |
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Term
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Definition
when a microorganism bears a mutation |
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Term
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Definition
random change in the DNA arising from errors in replication -random |
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Term
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Definition
results from exposure to know mutagens ex: ultraviolet radiation |
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Term
Two categories of mutagenic agents |
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Definition
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Term
Two categories of Mutations |
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Definition
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Term
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Definition
involve addition, deletion or substitution of single bases |
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Term
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Definition
when one ot more bases are inserted into or deleted from a newly synthesized DNA strand -changes the reading frame of the mRNA -nearly always results in a nonfunctional protein |
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Term
Point-mutation submutation: Missense mutation |
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Definition
results in different amino acid |
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Term
Point-mutation submutation: Nonsense mutation |
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Definition
results in a premature stop codon |
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Term
Point-mutation submutation: Silent mutation |
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Definition
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Term
Point-mutation submutation: Back-mutation |
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Definition
second mutation corrects effect of first |
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Term
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Definition
mutation are permanent and inheritable most are harmful but some provide adaptive advantages |
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Term
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Definition
when one bacterium donates DNA to another bacterium |
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Term
What is the end result of recombination? |
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Definition
a new strain different from both the donor and the original recipient |
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Term
What are easily exchanged among bacteria |
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Definition
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Term
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Definition
any organism that contains (and expresses) genes that originated in another organism |
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Term
Difference between plasmid and chromosomal fragments mode of transmission of genetic material in bacteria |
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Definition
-plasmid can replicate independently of the bacterial chromosomes -chromosomal fragments must integrate themselves into the bacterial chromosome in order to replicate |
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Term
What are the 3 means of recombination in bacteria |
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Definition
1. Conjugation 2. transformation 3. transduction |
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Term
Conjugation-- factors involved |
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Definition
-donor cell with pilus -fertility plasmid in donor -both donor and recipient are alive -bridge forms between cells to transfer DNA |
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Term
Conjugation-- Direct or indirect? |
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Definition
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Term
Transformation-- factors involved? |
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Definition
-free donor DNA (fragment) -live, competent recipient cell |
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Term
Transformation-- direct or indirect? |
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Definition
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Term
Transduction-- factors involved? |
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Definition
-donor is lysed bacteria cell -defective bacteriophage is carrier of donor cell -live recipient cell of same species as donor |
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Term
Transduction-- direct or indirect? |
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Definition
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Term
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Definition
cytoplamic bridge that lets two cells dock and transfer materials between them |
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Term
Stains of bacteria containing/and not the f factor |
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Definition
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Term
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Definition
bear genes for resisting antibiotics -can confer multiple resistance to antibiotics to a strain of bacteria |
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Term
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Definition
-the f factor is integrated into the chromosome -the copied chromosome will contain the f factor and chromosomal genes - recipient cell is now an Hfr with new henes |
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Term
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Definition
capturing DNA from solution - it is nonspecific acceptance of foreign DNA by a bacterial cell |
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Term
What are competent cells? |
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Definition
they are capable of accepting genetic material (the live cell) |
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Term
What is generalized transduction? |
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Definition
It involves a lytic bacteriophage
-during bacteriophage assembly, some bacterial host DNA is packaged into capsid with viral DNA |
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Term
What is specialized transduction? |
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Definition
-involves lysogenic bacteriophage transfer of only a few specific genes from one bacterial cell to another by means of a phage |
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Term
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Definition
jumping genes -they move from place to place in the genome, plasmids, and viral genomes -they disrupt the place they land -they mobilize other genes (like antibiotic resistance |
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