Micro Homeaid cards

• Genotype


  Potential traits of an organism (all genes) whether expressed or not.
• Phenotype


  observable traits expressed due to the environment conditions the organisms is grown in.
• Mutations


  heritable changes in DNA base sequences that affect phenotypic traits.
• Genotypes can change through

  1. Mutations 2. Horizontal Gene transfer
• Prototrophic Mutations


  wild type, grows on minimal media
• Auxotrophic Mutations


  Can't produce an essential enzyme or other molecules, will only grow on media containing the "missing substance"
• Types of Mutations

  1. wild-type 2. missense 3. nonsense 4. deletion/insertion
• wild-type mutation


  gene sequence found in most organisms; normal
• Missense mutations


  different amino acid in a protein
• Nonsense Mutations


  converts codon to stop codon
• Deletion/Insertion Mutations


  change in reading frame of mRNA
• Spontaneous Mutation


  occasional mistakes in DNA replication, transposon, normal low level radiation, one in a million
• Induced Mutations


  Mutagens: chemicals, radiation, carcinogens
• Genetic transfer- Gene transfer


  physical exchange of DNA between donor and recipient cells making a recombinant cell, homologous genetic recombination needed.
• Genetic Transfer- Homologous genetic recombination


  process of sharing or recombining part of a genome, stable incorporation of new DNA pieces into replicon, sequence must be similar to region of recipient's genome
• Conjugation


  DNA transfers between two living bacterial cells in physical contact, example sex pilus in gram negative
• F Plasmid of E. Coli steps

  1. Encodes proteins including F pilus 2. brings cells into contact 3. enzyme cuts plasmid 4. single strand transferred 5. complementary strands synthesized 6. both cells are now F+
• Transformation


  Transfer of naked DNA from donor to recipient (1."naked" DNA is released from often dead donor cell into the environment 2. competent recipient cell able to take up DNA from the environment 3. recipient cell integrates foreign DNA into its genome and become transformed)
• Example of Transformation

  Griffith's Rat experiment
• Transduction 


  involves using certain types of bacterial viruses: bacteriophages.
• Restriction Endonuclease Enzymes

  prokaryotic DNA cutting enzymes that are able to bind and cut to specific nucleotide sequence
• Restriction Endonuclease Enzymes - Polymerase Chain Reaction (PCR)

  DNA replication done in vitro
• Components of a Virus Bacteriophage

  1. Contains either DNA or RNA (can be single or double stranded, can be positive or negative stranded, positive mRNA is used for protein synthesis) 2. has a protein coat surrounding nuclei acid 3. may contain an additional layer of lipids around the protein in enveloped viruses
• Virus structure terms


  virion, nucleocapsid, capsid, envelope
• 3 Major Concerns of Taxonomy

  Identification, classification, and nomenclature
• Types of Bacteriophages 


  Virulent (Lytic) and Temperate (Lysogenic)
• Virulent (Lytic)


  phages enters and exist host, cell is lysed, process takes 30 mins
• Temperate (Lysogenic)


  no production of new virions
• Bacteriophage Infection Steps

  1. Attachment 2. Infection 3. Synthesis of Phage 4. Assembly 5. Lysis
• Lysogenic Phase


  give bacterial host new properties (like toxin production)-expression of viral genes can occur without virion production, environmental conditions causes damage to host cell- this damage is sensed by lysogenic phage and produces virions and exit from host before cell dies
• Latent Viruses


  not multiplying or causing disease- environment may trigger replication and disease
• Latent viruses 


  herpes zoster virus, chicken pox, and shingles
• Oncogenic Viruses


  Once inside host cell, alter growth and metabolism (cancerous transformation). Host cell can have increased rate of growth, altered chromosomes, altered surface molecules, and ability to divide indefinitely
• Retroviruses


  Enveloped single stranded RNA viruses, contain viral enzyme (reverse transcriptase), uses single stranded RNA in Viron as template to make single stranded DNA then uses single stranded DNA as template to make double stranded DNA to integrate and replicate in host chromosome
• Retroviruses


  HIV
• Reverse transcriptase


  the enzyme used to complete the transformation of single stranded RNA to single stranded DNA to double stranded DNA
• Fungi


  heterotrophic organisms; chitin in cell wall
• Algae


  simple photoautotrophs (light as energy CO2 as carbon source)
• Protozoa


  Microscopic heterotrophs that are not fungi
• Protist


  Eukaryotes that are not fungi, plants, or animals