Term
| viruses: alive vs. not alive |
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Definition
protein and nucleic acid, ability to infect cells, can reproduce but active only in direct association with content of living host, when in host grows, reproduces, regulates, gene expression, evolves VS. noncellular (nonucleus, cytoplasm), obligate intracellular parasite (reproduce in host), no metabolic activity outside cell (no enzymes or ribosomes)
so... viruses only "live" when inside a host cell |
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Term
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Definition
| metabolize (nourish, respire, synthesize, etc) and self-perpetuate (reproduce, adapt, etc) |
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Term
| discovering viruses (scientists and years) |
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Definition
PASTEUR = rabies
IWANOWSKI (1892)=TMV
Beijerink(1897)=coined term "virus"
Stanley(1935)=isolated virus particles from TMV
Jenner(1976)=small pox vaccination |
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Term
| viral genome / capsid / envelope (VIRION) |
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Definition
| inner nucleic acid (4-100 genes) / outer protein coat made of capsomeres (protects, delivers virus to host, determines shape) / membrane surrounding capsid that helps infect host |
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Term
| viruses: shapes, kinds, virulence |
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Definition
SHAPE: rod, sphere, helical, cubic, tails
KIND: depends on type of host (bacteriophage = bacterial virus)
VIRULENCE: measure of ability to cause disease (depends on receptor sites, speed of multiplication, host cell defenses) |
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Term
| simplified viral reproductive cycle in viral attack |
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Definition
| ADSORPTION (virus lands on receptor sites on cell surface) --> ENTRY (virus enzyme makes hole in cell and nucleic acid-viral genome injected) --> REPLICATION (host cell metabolism taken over by virus and produces viral genes) --> ASSEMBLY (virus pieces put together to make complete viroins) --> RELEASE (enzyme destroys host cell wall and new viruses are released to infect other cells) |
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Term
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Definition
1. phage uses its tail fibers to stick to specific eceptor sites on outer surface of E.coli cell
2. sheath of tail contracts, thrusting a hollow core through the wall and membrane of cell (phage injects its DNA into cell)
3. empty capsid of phage is left as a ghost outside the cell and cell DNA is hydrolyzed
4. cell's metabolic machinery is directed by phage DNA to produce phage proteins and nucleotides from cell's degraded DNA are used to make copies of phage genome
5. Phage parts come together and three separate sets of proteins assemble to form phage heads, tails, and tail fibers
6. phage directs production of lysozyme that digests bacterial cell wall and osmosis causes cell to swell and burst, releasing 100 to 200 phages. |
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Term
| lysogenic cycle(viral genome infects host and repliates, but does NOT destroy host) |
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Definition
1. virus DNA inserts into host DNA and remains inactive but when host reproduces the prophage (combined DNA) is passed into daughter cells
2. PROPHATE ACTIVITY: may block entry of other viruses, help cell produce aas, or stay hidden for many generations
3. ACTIVATION:prophage triggered to become active (temp change, nutrient supply, radiation, chemicals) so it enters the lytic cycle |
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Term
| bacterial defenses (3 things) |
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Definition
-natural selection = mutant bacterial strains favored with unrecognized receptor site for virus
-restriction nucleases = enzymes that cut up foreign DNA
-phages are also evolutionarily favored to resist these enzymes |
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Term
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Definition
ADENOVIRUS (double-stranded): respiratory disease, some cause tumors in certain animals
PARVOVIRUS(ss): roseola (kids get fever, rash, diharrea, etc), most depend on co-infection with adenoviruses for growth
PAPOVAVIRUS(ds): papilloma (human warts, cervival cancer),
HERPOVIRUS: herpes simplex 1 = cold sores, herpes simplex 2 = genital sores,
POXVIRUS(ds): smallpox, vaccima, cowpox |
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Term
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Definition
| ENTEROVIRUS, RHINOVIRUS, TOGAVIRUS(ss) (rubella, yellow fever, encephalitis-inflamation of brain) INFLUENZA VIRUS, PARAMYXOVIRUS (measles, mumpls), RHABDOVIRUS(ss) (rabies), ARENAVIRUS, CORONAVIRUS, RETROVIRUS(ss) (RNA tumor viruses like leukemia and HIV), REOVIRUS (diarrhea, mild respiratory diseases)REOVIRUS(ds) |
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Term
| defenses against viral diseases (3) |
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Definition
VACCINE: provides immunity (polio, rubella, measles, mumps, chicken pix, hepatitis B)
INTERFERONS: small proteins produced by body when cell is infected by cirus that hinders ability of virus to infect other cells
ACYCLOVIR: inhibities herpes virus DNA synthesis |
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Term
| retroviruses (rna viruses) |
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Definition
-contain RNA as genetic material that serve as a template for mRNA synthesis
-reverse transcriptase: enzyme that makes DNA from RNA template
-"retro" = genes copies backwards (viral RNA is transcribed into viral DNA using RNA POLYMERASE)
-retroviruses infect cells --> produces DNA copy of RNA genes --> insertes into host DNA 9provirus) --> new genome offspring |
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Term
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Definition
-circular
-glycopriteins on outside with viral and outer lipid envelope
-capsid inside with protein core, 2 identical strands of RNA, and RT |
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Term
| reproductive cycle of HIV |
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Definition
(HIV causes AIDS by mainly attacking victim's desease-fighting immune system)
1. HIV enters host cell
2. RT creates RNA-DNA hybrid from viral RNA that is eventually turned into DNA
3. DNA enters nucleus where the provirus is added into the chromosomal DNA
4.some RNA goes back to form new HIV with other viral proteins
5.new HIV budds off to go infect other cells |
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Term
| AIDS-RELATEED STUFF (3 things) |
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Definition
TRANSMISSION OF AIDS VIRUS: through exchange of bodily fluids (blood, semen, vaginal secretion, breast milk), or isolated from saliva, tears, brain fluid, amniotic fliid, and urine
SYMPTOMS (ARC..aids related complex): large lymph glands, tiredness, fever, loss of appetite, diarrhea, night sweats, wasting syndrome, nervous sstem damage
OPPORTUNISTIC ILLNESSES: pneumocystis carinii pneumonia is the leading cause of death, and Kaposi's Sarcoma is a deadly form of skin cancer |
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Term
| AIDS diagnosis and treatment |
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Definition
DIAGNOSIS: blood test finds HIB antibodies that is evidence of the infection
TREATMENT: no cure yet but there are drugs to slow the growth of the virus (AZT that inhibits reverse transcriptase), vaccines are not encouraged because HIV mutates rapidly |
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Term
| emerging viruses (2 things) |
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Definition
-sudden appearance of a cirus (ex, HIV, ebola)
-virus evolves, becomes widespread by infecting different host species and disseminating from small population) |
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Term
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Definition
-spreads through plasmodesmata and may cause stunted growth and decreased crop yield
-no cures so we need to develop resistant plant varieties instead
-horizontal transmission is when the insect carries the virus and vertical is when the virus is inherited from parent plant |
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Term
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Definition
| smal sequence of RNA that doesn't code for proteins but disrupts metabolism and stunts cell growth in plants vs. proteins that degenerate nervous system (mad cow) by converting normal cels to prions which accumulate to dangerous levels in the brain |
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Term
| oncogenes vs. proto oncogenes |
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Definition
| cancer-causing viruses/genes (tumor viruses) that upset normal balances controlling cell growth (RSV aka rous sarcoma virus, Hepatits B aka liver cancer, Epstein Barr aka mono, papilloma virus aka cervical cancer) vs. type of oncogenes that code for proteins that affect cell cycle that aren't yet oncogenes (normal cellular genes that regulate cell growt, division,a nd adhesion) |
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Term
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Definition
-oldest/simplest/mostest
-decompose, nitrogen cycle, photosynthesis, disease
-around 3000 genes with circular DNA tightly called plasmids wound up in dense region called nucleoid
-around 2000 mutations for each gene per day that increases genetic diversity |
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Term
| plasmids / archaebacteria vs. eubacteria |
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Definition
-small circular DNA separate from bacterial chromosome that replicate independently
-contains few genes that may confer advantages during stress
/
lack wall and include organisms in harsh conditions like no O2, salt, or hot temps vs. have peptidoglycan cell wall for protection (pollysaccarides linked with peptide chains) |
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Term
| identifying bacteria (3 things) |
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Definition
CELL SHAPES: coccus (diplococcus, streptococcus, staphylcoccus), bacilius, spirillium
CELL WALL: distinguished by rxn to special staining techniques (gram+ is thick peptidoglycan layer and - is thin pep layer with outer membrane)
MOVEMENTS: 1 or more flagella, lash, snake, spiral forward, glide slowly, or no movement |
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Term
| genetic recombination (3 things) |
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Definition
TRANSFORMATION: incorperation of naked, foreign DNA from surrounding environment into bacterial chromosome
TRANSDUCTION: phages transfer bacterial genes from one host cell to another - infection
CONJUGATION: direct transfer of genetic material between two bacterial cells that are temporarily joined - bacterial sex |
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Term
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Definition
-DNA transfer is one-way
-F+ cell (has F plasmid) grows sex pili to attach to F- cell
-CONJUGATION TUBE: temprary cytoplasmic bridge that forms from DNA transfer
-F plasmid replicates in F+ cell and a copy goes to F- cell (female) |
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Term
| R plasmids / advantage to antibodics |
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Definition
carry genes that protect bacteria from antibiotics and can be transfered during conjugation
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by using antiboitics to treat diseases, we help natural selection increase bacteria with genes for antibacterial resistance |
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Term
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Definition
TRANSPOSA BLE GENETIC ELEMNTS: "jumping genes" that are pieces of DNA that can move from one location to another in a cell's genome
INSERTION SEQUENCES: simplest transposons that code for TRANSPOSASE that catalyzes transposition by inserting transposon into DNA sticky ends
COMPOSITE TRANSPOSON: 2 insertion sequences are close together on chromosome so whole mass moves together as one big transposon |
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Term
| insertion of a transposon and creation of direct repeatse |
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Definition
1. transposase makes staggered cut DNA at target site called sticky ends
2. Transposase inserts transposon into gap
3. polymerase and ligase bonds free nucleotides at sticky ends |
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Term
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Definition
PROMOTER: place on DNA for RNA to attach polymerase
OPERATOR: on/off switch after promoter that controls access of RNA polymerase to genes
STRUCTURAL GENES: code for polypeptides |
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Term
| repressible vs. inducible genes (both negative feedback) |
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Definition
operon normally on where repressor is inative until corepressor binds, then operon is switched off and transcription of genes is repressed
vs.
operon usually off where repressor is acive wtihout corepressor, and inducer binds and inactivates repressor to switch on operon and transcribe genes |
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Term
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Definition
-regulates symthesis of repressible enzymes
1. repressor, protein, is continually produced by regulatory gene, but in an inactive form so that it cannot bind to operator and stop operon/transcription.
2. corepressor, small molecule that cooperates with repressor, binds to repressor to activate it (tryptophan in trp)
3. once repressor is activated it can bind to operon to switch off operon so RNA polymeras cannot bind to promoter |
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Term
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Definition
-regulated synthesis of inducible enzymes
1. usually, when lactose is absent, the repressor is active and the operon is off
2. when lactose is present, the repressor is inactivated by an inducer (in this case allolactase) to allow the operon to be turned on and transcription to occur |
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Term
| positive feedback with CRP |
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Definition
CRP = cAMP receptor protein, an allosteric regulator that makes transcription go faster by binding to promoter
-when low glucose levels, there are high cAMP levels so cAMP binds to CRP whihc binds to promoter an activates transcription
-when high glucose levels, low cAMP so CRP remains inactive and little transcription occurs |
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Term
| chromatin structure (5 things) |
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Definition
-single uninterrupted DNA molecule packed with a lot of protein in each chromosome
-histones are proteins that the DNA is wrapped around
-nucleosomes are "beads" made of DNA and histones that are attracted to eachother
-compact DNA decreases gene expression and transcription because ht is harder for enzymes to squeese in there
-many levels of chromatin packing (first around histones then into beads then beads compacted then those compacts looped then those loops looped into chromosome) |
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Term
| heterochromatin vs. euchromatin / junk DNA |
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Definition
| very tightly packed and not transcribed vs. true chromatin that can be transcribed becuase it is packed more loosely/ repetitive and unneeded DNA sequences |
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Term
| non-coding DNA (EXCEPT some multigene families will be expressed) |
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Definition
repetitive DNA: many copies of short nucleotide sequences (GAGAGA)
tandemly repetiive DNA (satelite DNA): sequences repeated in series (repetitive..junk..repetitive..junk)
multigene families: collection of identical or similar genes either clustered or dispesed (ex. rRNA, Hemoglobin)
pseudogenes: similar to functional genes but lack sites needed for gene expressoin
introns: noncoding DNA within genes that may help with gene regulation |
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Term
| evolution of genes such as hemoglobin |
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Definition
| duplication and mutations lead to more duplication and mutations that eventually lead to new genes |
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Term
| altering gene expression not from mutations (3 things) |
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Definition
GENE AMPLIFICATION: selective replication of certain genes during a particular stage of development
SELECTIVE GENE LOSS: genes lost in certain tissues
GENOME REARRANGEMENT: change of gene loci
->TRANSPOONS / RETROTRANSPOSONS: "jumping genes" / moe within genome by an RNA intermediate and is expressed
-> IMMUNOGLOBULIN GENES: genes to make antibodies rearrange as cells differentiate for increased diversity |
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Term
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Definition
MORNING GLORY FLOWER: normally all purple but movement of transposon to a locus that determines purple flower color destroys function of flower-color gene so the flower turns white
CORN: variations in corn color due to genes that can jump in genome to change the phenotype |
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Term
| DNA rearrangement in maturation of immunoglobulin antibody gene to control gene expression |
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Definition
| pre DNA contains many genes, but through deletion, transcription, and RNA processing and translation, only one of the gene is expressed (series of genes can be modified to express certain genes for certain antibodies) |
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Term
| controlling gene expression (4 things) |
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Definition
-expression of specific genes commonly regulated at level of transcription
-cell differentiation results from selective gene expression (all cells have same genes but fractions of genes activated or suppressed to produce differences in cell structure and function)
-bacteria adjust metaolism witih environmental change
-metabolic control regulated at 2 levels (regulate gene expression to vary number of specific enzymes present AND regulate activity of enzymes already present called negative feedback control) |
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Term
| opportunities for control of gene expression in eukaryotic cells (5 levels) |
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Definition
TRANSCRIPTIONAL CONTROLS: control elements = segments of noncoding DNA that help regulate transcription of a gene by binding proteins, enhancers = far away control elements where activator (a tipe of transcription factor) binds to enhancer and stimulates transcription by bending DNA to help position initiation complex (inhibitor may come in and block enhancer or change shape of activator)
TRANSCRIPT PROCESSING CONTROLS: govern modification of initial mRNA transcripts in nucleus (alternative RNA splicing and mRNA degradation)
TRANSPORT CONTROLS: determine which mature mRNA transcripts will be shipped out of the nucleus and into the cytoplasm for translation
TRANSLATIONAL CONTROLS: govern which mRNA molecules that reach the cytoplasm will be translated into polypeptide chains at ribosomes, and initiation phase can be blocked by preventing ribosomes to attach and inactivating initiation factor that bring together the mRNA, tRNA, and ribosomes
POST-TRANSLATIONAON CONTROLS: govern how the polypeptide chain becomes modified into functional protieins before being transported to areas of function (attach specific sugar or phosphate groups, eleave into smaller active fragments, or proteasomes degrade proteins |
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Term
| alternative RNA splicing / mRNA degradation to stop expression of parts of RNA |
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Definition
different mRNA molecules produced from same primary transcript depending on which RNA segments are treated as exons and introns (RNA transcripts of genes spliced in different ways -->produce different mRNA's --> produce diff polypeptides from one gene)
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rate at which enzymes destroy mRNA affect amount of protein made. some proteins bind to RNA and block degradation. altering the lenth of poly-A tail changes degredation rate (for example the rate is low in HB because you want a lot of it)
REMEMBER: for degradation you're not actually changing the RNA, just picking and choosing which part you want to be expressed) |
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Term
| chromatin modification (4 things) |
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Definition
-makes physical state of DNA more or less available for transcription
-DNA methylation: by adding CH3, genes and proteins are inactivated to prevent transcription
-Histone Acetylation/deacetylation: by adding or removing COCH3 to certain aa's of histone proteins, it neutralizes the histone tails/compacts them more which decompacts it when the nucleosomes are no longer attracted to eachother, meaning enzymes can get in easier / makes them more compacted
-epigenetic inheritance: inheritance of traits transmitted by mechanisms not directly involved in nucleotide sequence |
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Term
| proteasomes if you dont' want translated protein |
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Definition
1. enzymes attach ubiquitin to protein
2. proteasome recognizes ubiquitin and protein and unfolds it and places it in its central space (proteasome like trash can)
3. proteasome enzymes cut protein into smal peptides and they are degraded
4. proteasome and ubiquitin recycled |
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Term
| proto-oncogene --> oncogene |
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Definition
either:
TRANSPOSITION/TRANSLOCATION: gene moved to new locus with new controls where normal growth-stimulating protein is in excess
GENE AMPLIFICATION: multiple copes of the gene create normal growth-stimulating protein in excess
POINT MUTATION: point mutation within gene creates hyperactive or degradation-resistant protein |
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Term
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Definition
-produce proteins that help prevent uncontrolled cell growth
-repair damaged DNA by preventing accumulation of cancer-causing mutations, controls adhesion of cells to eacohother or to ECM, inhibits cell cycle
-example: p53 tumor supressor gene: promotes synthesis of growth inhibiting proteins (mutations here common in human cancers - over 50%) |
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Term
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Definition
-more than 1 mutation seem necessary for cancer cell (as you get older you have a buildup of these muations)
-familial tendencies of certain cancers like colon and breast
-defective DNA repair mechanisms, radiation, et. causes more rapid accumulation of mutations required for cancer
-viruses involved in 15% of human cancers (leukemia, liver, cervical, hpv) |
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Term
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Definition
BRCA 1 and 2 alleles should inhibit growth of breast cancer cells, so when they are mutated shit goes doownn. (2% probability for individual homozygous normal, over 60% of developing breast cancer before 50 for inheriting mutant BRCA1)
/
in the colon you lose tumor-supressor cell gene APC (adenomatous polyposis coli) so a small benign growth called a polyp forms, then ras oncogene is activated so you lose tumor-supressor gene DCC (deleted in colorectal cancer) that causes larger benign growth (adenoma) then you lose p53 and have aditional mutations that causes malignant tumor (carcinoma)...bloody stool when polyp is ripped off and grows back multiple times before it grows into adenoma |
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Term
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Definition
| controls kinase cascade and produces protein that stimulates cell cycle, so when mutated or activated (30% of cancers) there is a continuous cascade (usually growth factors will bind to receptor, then ras gene, which produces a protein to stop the cascade, but when ras gene is mutated/activated into oncogene, there are no growth factors that will be able to stop cascade. |
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Term
| GENE CLONING WITH BACTERIAL PLASMIDS |
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Definition
purposes: prepare well-defined, gene-sized pieces of DNA in multiple identical copies
steps:
1. isolate two kinds of DNA ex. plasmid and DNA with gene of interest
applications: gene for pest-resistance introduced into plants, alter bactieria for toxic waste, HGH for dwarfism, blood clots
application: amp n gene can be cloned to make E.Coli cells resistant to the antibiotic ampicillin |
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Term
| USING RESTRICTION ENZYMES TO MAKE RECOMBINANT DNA |
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Definition
1. restriction enzyme cuts DNA and other fragment
2.fragment added to DNA and they stick together because of base pairing
3. DNA ligase seals the strands
applications: gene therapy |
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Term
| CLONING EUKARYOTIC GENE IN A PLASMID (4 things) |
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Definition
-scientists use eukaryotic cells such as yeasts as host for cloning and expressing genes of interest because they are as easy to grow as bacteria, but still have plasmids
-yeast artificial chromosomes (YACs) combine essentials of eukaryotic chromosome (origin for DNA replication, centromere, two telomeres) and foreign DNA
-electroporation: brief electrical pulse applied to solution containing cells creates tempary holes in their plasma membrane where DNA can enter
-reason to use eukaryotic host cell: many eukaryotic proteins will not function unless they are modified after translation (addition of carb or lipid group, etc) and bacteria and yeast can't carry out these modifications so use of host cells from animal cell culture may be necessary (can insert small needle) |
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Term
| IDENTIFYING CLONES CARRYING A GENE OF INTEREST |
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Definition
| screen all colonies with recombinant plasmids fo a clone of cells containing gene of interest (many methods including nucleic acid hybridization, nucleic acid probe) |
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Term
| NUCLEIC ACID PROBE HYBRIDIZATION (to identify clone carrying gene of interest after the gene of interest has been inserted into bacterial plasmid and reproduced many times) |
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Definition
purpose: use DNA probe of unknown gene to detect cloned gene (southern blotting)
steps:
1. transfer cells of bacterial colonies containing cloned segments of foreign DNA to filter
2. treat cells on filter to denature DNA
3. add probe to fllter (radioactive complimentary DNA sequences of one you want)
4. autoradiograph that plate and master plate containing colonies of gene of interest, then compare autographs
application: |
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Term
| POLYMERASE CHAIN REACTION |
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Definition
purpose:to rapidly amplify copies of DNA from small or old sample
steps:
1.DNA with desired sequence is added to heat that separates DNA strands
2. cooled to allow primers to hydrogen-bond
3. heat-resistant DNA polymerase adds nucleotides to the 3' end of each primer(short, synthetic, singlestranded complimentary DNA that determines segment to be amplified)
4. sequence repeated until you have many (1st cycle yeilds 2 DNA molecules, 2nd 4, 3rd 8, etc)
application: amplify DNA from ancient wooly mammoth, small sample at crime scene, to find genetic disorder from one tiny piece of DNA |
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Term
| GEL ELECTROPHORESIS (to identify clone carrying gene of interest after the gene of interest has been inserted into bacterial plasmid and reproduced many times) |
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Definition
purpose: to separate nucleic acids/proteins based on size (used to ID, isolate, or purify particular DNA molecule)
steps:
1. 3 samples placed in wels in glass wtih gell where electrodes are attached and voltage applied
2. DNA (-) migrate to +, where rate of movement is based on size/length
3. current is turned off and teh DNA is in bands based on its size where smallest ones are furthest down the gel
USED: for forensics, you can do it for defendants blood and other blood to see if they are the same
application:finding if person has sickle-cell alleles in hemoglobin, checking if blood from crime site is the same as different samples |
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Term
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Definition
purpose: to analyze restriction fragments
steps:
1. add DNA to restriction enzyme (restriction fragment preparation)
2. put restriction fragments into electrophoresis
3. blot it in alkaline solution with sponge and nitrocellulose paper under paper towels
4. hybridization with radioactive probe (probe is complimentary to sequence you want)
5. rinse away unattached probe and autoradiography
applications: identify carriers of sickle-cell allele or 2 mutant alleles, usually used to identify carriers of genetic diseases |
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Term
| DNA SEQUENCING (to identify clone carrying gene of interest after the gene of interest has been inserted into bacterial plasmid and reproduced many times) |
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Definition
purpose: use restriction sites to determine aa sequence or proteins
steps:
1. DNA fragment is divided into 5 portions, and each is treated with a different one of 4 nucleotides in dideoxy form
2. New strands are synthesized in test tube with dd form that prevents further synthesis
3. set of labeled strands are produced and new DNA strands are separated by gel electrophoresis
4. sequences is read by autoradiography:longest fragment ends in ddG so G is last base in strand
application: Human Genome Project |
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Term
| DNA MICROASSAY OF GENE EXPRESSION LEVELS |
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Definition
1. isolate mRNA
2. make cDNA by reverse transcription, using flourescently labeled nucleotides
3. hybridization: apply the cDNA mixture to a DNA microarray (txed to each spot on microscope slide are copies of a short single-stranded DNA molecule representing one gene of the organisms, a different gene in each spot
4. rinse off excess cDNA, scan microarray for flourescence (each flourescence spot represents a gene expxpressed in the tissue sample
application: comparing patterns of gene expression in breast cancer tumors and non-cancerous breast tissue has resulted in more informed and effective treatment protocols, much learned about C. elegans life cycle |
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Term
| DIAGNOSIS OF DISEASE/GENE THERAPY |
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Definition
PCR and nucleic acid probes help track down pathogens
application: because sequence of HIV RNA is known, PCR can be used to amplify and detect the otherwise elusive infection, also sickle-cell disease, hemophelia, cystic fibrosis, Huntington's, DUchenne muscular dystrophy (possibly identified before birth!)/
1. insert cloned gene (RNA version of normal allele because patient doesn't have normal allele) into retrovirus
2. let retrovirus infect bone marrow cells that have been removed from patient and cultured
3. viral DNA carrying normal allele inserts into chromosome
4. inject engineered cells into plants to fix bones and immune system
applications: gene inserted to Severe Combined Immunodeficiency (SCID) patient's bone marrow cells so patient's bone marrow cells will begin producing missing protein (doesn't produce vital enzyme because of single defective gene) |
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Term
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Definition
manipulation of genetic material for practical purposes (recombinant DNA technology provides means to transplant genes from one species into genome of another)
steps:
1. isolate plasmids from bacterial cells
2. insert foreign genes into plasmids and recombine DNA
3. return plasmids to bacterial cells
4. close recombinant DNA when bacteria reproduce |
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Term
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Definition
manipulation of living organisms or their complnents to perform practical tasks or provide useful products
-protein product ex. insulin or Human growth homrone
-endow organism particular metabolic capability like oil-eating bacteria
-make more gene copies for study ex of the human genome |
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Term
| 3 things needed for DNA manipulation |
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Definition
RESTRICTION ENZYMES: specific enzymes chosen chosen to cut and insert foreign gene near desired promoter ( recognize short, specific nucletide sequences in DNA called restriction sites and cut at specific points within these sequences creating sticky ends)
VECTORS: transfer agent that moves recombinant DNA into cells ex. bacterial plasmids, viruses, yeast plasmids |
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Term
| RESTRICTION FRAGMENT LENGTH POLYMORPHISM |
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Definition
purpose: fragments made with restriction enzymes so they can be examined
steps: using restriction fragment patterns to distinguish DNA from different alleles using electrophoresis once fragments are cut |
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Term
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Definition
-insert bovine growth hormone for more milk production and weight gain in cattle
-transgenic organisms (organisms that have a new gene introduced from another animal) used to improve food yield,=
-cloning to make sheep have better wool,etc) |
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Term
| why we manipulate plant genes (4 things) |
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Definition
| -improve food value of crops (ex. golden rice) -grow plants resistant to herbicides, viruses, and insects -delayed spoilage in tomatoes -nitrogen-fixing plants - grow plants that can fix nitrogen all by themselves |
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Term
| genetic engineering in plants (Ti plasmid as vector) to PRODUCE TRANSGENIC PLANTS |
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Definition
purpose: transferring useful traits from one plant variety to another using TI plasmid as vector
1. using same restriction enzyme to cut both Ti plasmid and gene of interest
2. incubation with both to create recombinant DNA
3. introduce into plant cells in culture and regenerate plant with new gene (delayed ripeness, resistance to spoiling, improved nutrition,making strawberrys huge, making apples resist bugs and rotting, possibly create superweeds) |
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Term
| examples of cloned human gene products |
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Definition
| insulin, growth hormone for pituitary dwarfism, erythroprotein for anema, factor Vii and IX for hemophilia, antibodies for infection diseases, atrial natriuretic factor for high bp, tissue plasminogen factor for heartattack/stroke, IL-2, TNF, interferons for cancer |
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Term
| ethical/safety questions regarding genetic engineering (3 things) |
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Definition
-is it ethical to:
treat an egg/sperm with human gene therapy
control genetic makeup of human population
-is it possible to:
create new hazardous pathogens
negatively effect environment with genetically engineered organisms
form superweeds resistant to herbicides, pesticides, etc
-harmful side effects of new medical products |
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Term
| host range vs. host specific |
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Definition
| limited range of host cells that a virus can infect becuase of lock-and-key effect vs. how certain viruses can only infect certain hosts |
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Term
| virulent phage vs. temperate phage vs. prophage |
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Definition
| page that reproduces only by lytic cycle vs. phage that can use both lytic and lysogenic vs. in lysogenic cycle where phage DNA ias been inserted into normal DNA |
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Term
| combinatorial control vs. coordinately controlled genes |
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Definition
| specific combo will activate transcription when appropriate activators are present (precice time or particular cell type) vs. genes of related function that need to be turned on/off at the same time |
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Term
| protein processing and degredation |
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Definition
| polypeptides are processed by enzymes and other proteins to yield functional protein molecules, or broken down. |
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Term
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Definition
| complete set of plasmid clones, each carrying copies of a particular segment from innitial genome |
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Term
| practical applications of DNA technology (3 things) |
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Definition
FORENSIC EVIDENCE: DNA testing to identify victim, body fluids or blood to determine blood type, DNA fingerprining PCRs
PHARMACEUTICAL PRODUCTS: products used to fight off symptoms, infections, etc like HGH
ENVIRONMENTAL CLEANUP: certain microorganisms can help clean up oil spills, etc. (detoxing specific toxic wastes found in spills and waste dumps) |
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