Microbiolgy Chapter 10

Question 1

what is taxonomy

Answer 1

The science of classifying organisms
Provides universal names for organisms
Provides a reference for identifying organisms

Question 2

Systematics or Phylogeny

Answer 2

The study of the evolutionary history of organisms
All Species Inventory (2001–2025)
To identify all species of life on Earth

Question 3

Classification vs identification

Answer 3

Classification
Placing organisms in groups of related species
Lists of characteristics of known organisms
Identification
Matching characteristics of an “unknown” organism to lists of known organisms
Clinical lab identification

Question 4

membrane lipids of archaea vs bacteria

Answer 4

archaea has branched carbon attached to glycerol by ester linkage while bacteria has straight carbon

Question 5

Phylogenetics

Answer 5

Each species retains some characteristics of its ancestor
Grouping organisms according to common properties implies that a group of organisms evolved from a common ancestor
Anatomy
Fossils
rRNA

Question 6

Classification of Prokaryotes
Prokaryotic species: a population of cells with similar characteristics
culture vs clone vs strain

Answer 6

Culture: grown in laboratory media
Clone: population of cells derived from a single cell
Strain: genetically different cells within a clone

Question 7

Classification of Eukaryotes

animalia vs plantae vs fungi vs protista

Answer 7

Animalia: multicellular; no cell walls; chemoheterotrophic
Plantae: multicellular; cellulose cell walls; usually photoautotrophic
Fungi: chemoheterotrophic; unicellular or multicellular; cell walls of chitin; develop from spores or hyphal fragments
Protista: a catchall kingdom for eukaryotic organisms that do not fit other kingdoms
Grouped into clades based on rRNA

Question 8

Classification of Viruses

Answer 8

Viral species: population of viruses with similar characteristics that occupies a particular ecological niche

Question 9

Identification Methods: 3 main methods

Answer 9

Morphological characteristics: useful for identifying eukaryotes
Differential staining: Gram staining, acid-fast staining
Biochemical tests: determines presence of bacterial enzymes

Question 10

other tests for identification

Answer 10

Phage typing
Fatty acid profiles (FAME)
Flow cytometry
Genetics

Question 11

Serology is the scientific study of plasma serum and other bodily fluids.
serology tests

Answer 11

Combine known antiserum plus unknown bacterium
Examples
Slide agglutination test
Enzyme-linked immunosorbent assay (ELISA)
Known antibodies 
Unknown type of bacterium
Antibodies linked to enzyme
Enzyme substrate

Question 12

slide agglutination result

Answer 12

positive = specs clumping

negative plain no clumping

Question 13

ELISA is a test that uses antibodies and color change to identify a substance.

Answer 13

Enzyme’s substrate is added, and reaction produces a product that causes a visible color change for positive direct and indirrect

Question 14

Western Blot

Answer 14

is a widely used analytical technique used to detect specific proteins in a sample of tissue homogenate or extract. It uses gel electrophoresis to separate native proteins by 3-D structure or denatured proteins by the length of the polypeptide.

Question 15

Flow Cytometry

Answer 15

Uses differences in electrical conductivity between species
Fluorescence of some species
Cells selectively stained with antibody plus fluorescent dye

Question 16

The fluorescence-activated cell sorter (FACS)

Answer 16

Fluorescence-activated cell sorting (FACS) is a specialized type of flow cytometry. It provides a method for sorting a heterogeneous mixture of biological cells into two or more containers, one cell at a time, based upon the specific light scattering and fluorescent characteristics of each cell. I

Question 17

Genetics

Answer 17

DNA base composition

Guanine + cytosine moles% (GC)

Question 18

DNA fingerprinting how does it work

Answer 18

Electrophoresis of restriction enzyme digests

Question 19

DNA hybridization

Answer 19

Probes
Microarrays
FISH

Question 20

A DNA probe used to identify bacteria

Answer 20

Cloned DNA fragments are marked with fluorescent dye and separated into single strands, forming DNA probes.

Question 21

DNA chip microarray

Answer 21

A DNA chip can be manufactured to contain hundreds of thousands of synthetic single-stranded DNA sequences. Assume that each DNA sequence was unique to a different gene.

Question 22

Fluorescent in situ hybridization

Answer 22

Add DNA probe for S. aureus

Question 23

cladogram

Answer 23

Determine the sequence of

bases in an rRNA molecule for each organism. Only a short sequence of bases is shown for this example.