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Details Title: virus and bacteria Description: shs Total Flash Cards: 87 Created: 02/09/2005 18:03:33	To study from this set of flash cards, or to create your own your own study flash cards, register HERE. If you are already a registered user, CLICK HERE.
Cards Term recombination Definition something new in the dna and rna Term animal cell Definition eukaryotic Term bacterium Definition prokaryotic Term virus Definition neither prokaryotic or eukaryotic Term virus structure Definition genome - double and single stranded rna and dna - linear and circular strands - 4 to several 100 genes - capsid is protein coat Term capsid Definition composed of smaller protein subunits called capsomeres Term virus envelope Definition surrounds capsid - composed of cell membran of host cell w/ proteins and glycoproteins of the virus - aids in infecting the cell Term viral reproduction Definition obligate intracellular parasites, host range, viral genome, replication, new virus Term obligate intracellular parasites Definition can only reproduce inside a host cell Term host range Definition hosts which a particular virus can infect. viral coat fits into the cell membrane of the host by lock and key method Term viral genome in replication Definition enters the host cell and the capsid is degraded Term viral dna in replication Definition uses host cells machinery to replicate its nucleic acid (replication) and produce capsid proteins (trasncription and translation) Term ***dna viral genome*** Definition enzyme of replication - dna polymerase of host cell Term ***rna viral genome*** Definition enzyme of replication - rna replicase and reverse transcriptase Term ***rna replicase*** Definition replicates viral rna Term ***reverse transcriptase*** Definition uses viral rna as template to make dna (cdna) - host cell machinery used in cdna for transcription of viral genome and transcription + translation of capsid protein Term lytic cycle Definition host cell is killed by lysis - releases new viruses Term lysogenic cell Definition viral genome is replicated w/o killing the host cell - it is inserted Term bacteriophage Definition virus that infects bacteria Term virulent phage Definition reproduces w/ lytic only Term temperate phage Definition uses lytic or lysogenic Term virion Definition free virus Term prophage Definition viral dna inserted into host dna Term glycoprotein of envelope Definition binds to specific receptors on the host cell membrane Term capsid in envelope Definition digested Term vesicles in envelope Definition transport glycoproteins to the cell membrane where they cluster Term retrovirus Definition special group of rna viruses that have reverse transcriptase Term HIV Definition immunodeficieny virus - causes aids - infects Th cells lymphocytes - recognizes CD4 protein receptor on the host cell - 100% mortality Term emergent viruses Definition appeared recently - cause mutations in existing viruses and tranfers the virus betwween species Term bacteria against viral infections Definition mutations in membranes receptors - restriction enzymes - enzymes protect from foreign dna - cuts dna between specific bases within specific nucleotide sequences Term animal cells against viral infections Definition immune system - vaccines Term vaccines Definition dead or weakened form of virus - trigger the immune system to produce antibodies that have memory cells Term memory cells Definition prevent a second infection from the same virus (immunity) Term viroids Definition small molecules of dna that infect plants Term prions Definition small protein molecules that can cause infection (mad cow disease) Term hypothesis of prions Definition prion attaches to normal proteins, causing the normal protein to change into the prion shape Term bacteria structure Definition monera kingdom - prokaryotic - single circular chromosome in nucleiod region Term bacteria replication Definition theta replication - one origin of replication - 5' to 3' - dna attaches to bacterial membrane and will seperate as the mesosome forms - reproduction is binary fission Term plasmids Definition small circular dna found in the cytoplasm - dna contains genes - self-replicating, but usually replicate within chromosomal dna - 2 classes (episomal and nonepisomal) Term episomal plasmids Definition integrate in the chromosomal dna - f-plasmid contains genes from a production of a conjugation tube (allows for sexual reproduction) Term nonepisomal plasmids Definition remains seperate from chromosomal dna - r-plasmid contains genes for antibiotic resistance Term bacterial reproduction Definition asexual is binary fission - sexual is f+ and f- bacteria Term pilus Definition attaches to another bacterial cell and forms a conjugation tube Term conjugation tube Definition cytoplasmic channel Term f+ bacteria Definition contains f plasmid (male) Term f- bacteria Definition no f plasmid (female) Term hfr bacteria Definition has f plasmid that is integrated (high frequency recombinant) Term f+ and f- bacteria Definition f+ attaches to f- cell through pilus - tubes connect cells - f plasmid replicates - new copy travels through tube - f- cell is converted to f+ cell (no exchange os bacterial chromosomal genes) Term f+ to hfr conversion Definition f plasmid integrated into chromosomal dna - hfr cell has f plasmid Term hfr and f- bacteria Definition hfr attaches to f- through pilus - tube forms - f plasmid replicates and travels to f- cell - replication occurs in one direction - small piece of plasmid replicates then chromosomal gene replicates - tube breaks before transfer is complete - f- is still f- (new combinations) Term crossover Definition occurs between chromosomal genes brought in by f plasmid and chromosomal genes on f- cell Term transformation Definition cells pick up genetic info from surrounding environment - avery macleod and mccarty - bacterial cells can be manipulated to pick up plasmids from environment Term transduction Definition virus carries genes from one bacterial cell to another - 2 types - generalized is random movement and specialized is specific movement Term transposons Definition jumping genes - they can move within chromosomes of cell because of transposase enzyme - inverted repeat dna sequences at each end Term different genes Definition active in different cells at different times in the life of a cell Term active genes Definition undergoing transcription and traslation - turned on Term inactive genes Definition turned off - undergoing trascripton and trasnlation Term promoter Definition region of the dna which binds rna polymerase - TATA box Term structural genes Definition genes that code for structural protein or enzyme Term regulatory genes Definition code for repressor of regulatory protein Term positive control Definition mechanism of a gene control that enhances transcription (CAP-cAMP) Term negative control Definition mechanism of gene control that inhibits trasncription (repressible operon, inducible operon) Term repressible operon Definition genes normally on and can be turned off (negative feedback) - anabolic pathways and trp operon Term inducible operon Definition genes normally off and can be turned on (positive feedback) - catabolic pathways and lac operons Term operon Definition region of the prokaryotic chromosome that includes promoter, operator, and structural genes Term operon system Definition allows genes involved w/ metabolic pathway to be transcribed and translated as a unit Term lac operon Definition lactose breakdown - operon starts off and is induced Term non-histone protein Definition regulatory and amount varies Term histone protein Definition helps package the dna and amount is constant Term dna packaging Definition dna wraps around nucleosome - can be pulled together as nucleosomes are packaged and looped around each other - euchromatin is active dna and heterochromatin is inactive (barr bodies) Term nucleosome Definition "bead" - basic unit of dna packaging - contains 4 types of histone proteins that connect to adjacent beads Term genome organization Definition 97% does not code for protein - tandemly repetative dna (satellite dna) - interspersed dna - single copy dna Term regular satellite dna Definition centromere and telomere Term minisatellite dna Definition genetic disorders Term microsatellite dna Definition dna fingerprinting Term interspersed dna Definition alu elements - can be caused by transposons Term single copy dna Definition functional genes and pseudogenes Term multigene families Definition genes that are similar or identical in nucleotide sequence - arise from duplication mutation during dna replication - 2 types (identical and nonidentical) Term gene amplification Definition replication of specific genes during certain times (egg cell-cleavage and cancer cells) Term gene rearrangement Definition transposons and retrotransposons (replicated transposons) Term dna mehtylation Definition inactivates genes (barr bodies) Term histone acetylation Definition acetyl group placed on a histone protein loosens dna and allowes for increased transcription factor binding Term enhancer Definition region of dna that binds transcription factors Term transcription factors Definition can function as activators of repressors Term translational control Definition lifespan of mrna and prevent initiation of translation-mrna from attaching to ribosome Term post-translational control Definition protein - modification of protein - zymogen form (inactive) - lifespan protein Term cancer Definition mutations in genome - physical environmental factors - oncogenes - proto-oncogenes (produce proteins regulating normal cell growth) - tumor-supressor genes (produce proteins that inhibit cell growth)