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Flashcards in Exam 2 Deck (44):
1

Change in Number of Kingdoms and Classification

Carl Woese contributed the 3 domains because we know more due to the invention of the microscope

2

Contributions of Carl Linnaeus

Hierarchy clustering- Kingdom, Phylum, suphylum, class, order, familly, genus, epithet, strain

Binomial Naming - Homo Sapien (Genus Species)

3

Taxonomy

The study that names organisms based upon specific characteristics

4

Carl Woese

3 Domains of Life (Bacteria, Archea, Eukaryot)

RNA Hypothesis of start of all life

Quantitative Taxonomy - ribosomal RNA

5

Molecular Clock

The assumption that genetic change can be tied to a unit of time This is false, genetic change is not constant, it is highly variable

6

Pan Genome

The results from the paper on the 61 E. Coli Genomes included a pan genome which includes core genome which are genes present in all strands (6%), dispensable genome which are gene present in 2 or more strands and unique genome which are genes unique to the strand. It is suggested that horizontal gene transfer is the reason so that what we thought of as clear lines between species turns out to be more of a continuous border.

7

Heredity

Passing of gene from parent to offspring

8

Chromosome

A piece of DNA

9

Nucleoid

Condensed DNA, no nucleus

10

Supercoiling

Packaging by twisting DNA, typically a figure 8

11

Plasmid

Extra Chromosomal DNA, a mechanism for horizontal gene transfer

12

Transformation Diagram

Rat Diagram

A image thumb
13

Transformation

DNA is taken into the cell, naked DNA is taken into a competent cell and recombination in new cell

14

Transduction

Bacteriophage

Virulent - cell Death

Temperate - Enter lytic and lysogenic cycles

Specialized - requires a Prophage

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Conjugation

Direct Cell to Cell contact, bacteria to bacteria transfer

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Gene Cloning

Remove DNA from host cell, remove plasmid from bacterial cell. Recombine host DNA with plasmid and insert back into bacteria. Add as specific chemical to induce production of specific antibiotic or insulin.

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Ectoparasite

Parasite on the outside of host

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Endoparasite

Parasite on the inside of host

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Permanent Parasite

Stays forever

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Temporary Parasite

Eventually leaves

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Obligatory Parasite

Spend part of lifecycle in/on host (most parasites)

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Facultative Parasite

Free living, obtain nutrients from host, skin fungi

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Accidental Parasite

Invade organisms other than normal host ticks that bite animals, instead bite humans

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Biological Vector

Parasite undergoes part of life cycle before being passed on

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Mechanical Vector

The means of transmission in which a parasite does not undergo part of its lifecycle

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Definitive Host

Harbors a parasite through parasites reproductive life cycle

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Intermediate Host

Harbor a parasite during other portions of parasites life cycle

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Reservoir Host

Infected organism that makes the parasite available for transmission to other hosts

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Fungal Reproductive Cycle

A image thumb
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types of parasites

Fungi, Bacteria, Viruses (broad range of organisms are parasites)

31

Hyperparasitism

When a parasite carries other parasites, a malaria carrying mosquito, mosquito is the vector

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Viral Host Range

What organisms can the virus infect

33

Viral Specificity

What type of cells within the host does it infect

34

Virus Classifications

Classified by nucleic acid, DNA, RNA, single or double stranded, envelope vs naked

35

Naked Vs Enveloped

Capsomers, Capsid make up the nucleocapsid. Has an plasma membrane with enveloped virus.

36

5 Major Characteristics of Prions

Virus-Like proteins

heat resistance

not destroyed by dnase or rnase

sensitive to protein denaturing agents

Have direct pairing of amino acids

37

Disinfectant vs Sterilization

Disinfectant reduces the number of bacteria so reduces risk of infection, however does not kill spores. Sterilization kills all

38

Chemical Means of disinfecting

Soaps and Detergents - Cationic (+) or Anionic (-)

Acids/Alkalis - Alter pH

Heavy metals - Silver, mercury

Halogens - Chlorine, iodine

Alcohols - Ethanol, disrupt membrane

Phenolics - Disrupt membrane, denature

Oxidizers - Ozone

Alkylating Agents - Damage proteins adn nucleic acid by adding a methyl group

39

Physical Means of disinfecting

UV Light

Visible light

Heat

Pressure

Temperature

Desiccation - dry things out (freeze dry)

Osmotic Pressure - salt

40

Characteristics of a Great Disinfectant

Fast-acting Stable around organics Non-toxic Wide Spectrum Non-damaging to materials Easy to prepare stable readily available inexpensive no offensive odor

41

Mechanisms of Antibiotics

1. Inhibit cell wall synthesis 2. Disruption of cell membrane 3. Inhibit protein synthesis 4. Inhibit nucleic acid synthesis 5. Action of Antimetabolites

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Mechanisms of Resistances

Altered Target - genetic change that makes the target different i.e. a change in the cell wall that no longer allows it to bind

Altered Membrane Permeability - increase drug efflux

Novel Enzyme Activity - Develop enzymatic activity to breakdown or modify drug

Enzyme affinity alteration - increase in substrate affinity, out competes with drug

New Metabolic capabilities - change methods of metabolising

43

Temperate Virus

DNA Adsorption

Attachment cell Host

Injection

Lytic Pathway - Viral DNA replicates, induction, virus particles assemble, cell lysis (SICK)

Lysogenic Pathway - Viral DNA is integrated into host DNA, Prophage, Lysogenized cell, Cell division (No symptoms)

44

Benefits of Genetic Diversity

Stay alive

Gene pools

Evolution not extinction