Exam 3 classification and identification

Question 1

taxonomy

Answer 1

science of classifying organisms

-shows degree of similarity among organisms

Question 2

Study of phylogenetic relationships

Answer 2

-used to just be plants and animals
-then prokaryotes vs eukaryotes
-then fungi
used to be phenotypic classification
all species inventory

Question 3

3 domains

Answer 3

proposed by Woese

• Eukaryotes, Bacteria, and Archaea
• used sequence of nucleotides in 16s of prokaryote’s rRna and 18s of eukaryote’s
• Eukaryotes include kingdoms: fungi, plantae, animalia, and protists

Question 4

Why rRNA in classification?

Answer 4

• its in all living cells
• it has similar function in all cells
• it is well conserved
• doesn’t take mutations easily –> when it does, it makes an evolutionary shift

Question 5

Phylogenetic tree

Answer 5

• Grouping of organisms according to common properties
• fossils
• genomes (compare expected rate of mutation with observed rate)
• groups of organisms from common ancestor (each species retains some characteristic of ancestor)

Question 6

Taxonomic heirarchy

Answer 6

• Series of subdivisions developed by Linnaeus to classify plants and animals
• Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species

Question 7

Eukaryotic species

Answer 7

group of closely related organisms that breed among themseles

Question 8

Prokaryotic species

Answer 8

• don’t breed among selves and don’t have own kingdom

- population of cells with similar characteristics

Question 9

culture

Answer 9

bacteria grown in lab media

Question 10

clone

Answer 10

population of cells derived from single parent

Question 11

strain

Answer 11

genetically different cells within clone

-subspecies

Question 12

classification

Answer 12

placing organisms in groups of related species

-lists of characteristics of known species

Question 13

identification

Answer 13

matching characteristics of an unknown organism to the lists of known organisms

Question 14

Bergey’s Manual of systematic bacteriology

Answer 14

• doesn’t classify bacteria or show relationships
• based on physical and chemical characteristics, not evolution
• morphology
• staining
• biochemical tests (enzyme production, oxygen requirements, carbohydrate utilization)
• dichotomous key

Question 15

enterotube

Answer 15

one tube with media for 15 biochemical tests

-rub needle in bacteria, stick it in tube, incubate tube, calculate number of positive tests

Question 16

Serology

Answer 16

• the study of immune responses of bacteria in serum
• serum is a component in blood
• Slide agulation test, ELISA test, western blotting
• super specific –> can differentiate between subspecies

Question 17

Slide aggulation test

Answer 17

• bacteria clump together when mixed with the antibodies that’re created in response to the bacteria
• the antibodies that accumulate determine the bacteria

Question 18

Enzyme-linked immunosorbent assay (ELISA)

Answer 18

• known antibody and unknown bacteria are added to well
• add second antibody with enzyme attached
• enzyme substrate is added and induces a color change
• reaction + color change determines type of bacteria

Question 19

western blotting

Answer 19

• identifies antibodies in patient’s serum
• confirms HIV and Lyme
• get patient’s blood protein
• mix it with protein that attacks certain antibodies
• add glowing proteins to above protein

Question 20

Phage typing

Answer 20

• Test for determining which phages a bacteria is succeptible to
• create bacteria lawn on plate
• separate plate into grid
• add different phages to different grid sections
• if plaque (clearing) happens in grid square, then the phage lysed the bacteria
• super specific

Question 21

DNA fingerprinting

Answer 21

• uses restriction enzymes which are naturally found in bacteria
• cuts genome at specific base pair sites
• uses electrophoresis to separate fragments by size
• match fragments to known database
• negative phosphate backbone attracted to positive charge

Question 22

DNA sequencing

Answer 22

• compare GC%

- two organisms that’re closely related will have similar GC percentages

Question 23

Polymerase chain reaction

Answer 23

• amplifies small part of DNA
• includes target protein, DNA primers, taq polymerase , and nucleotides
• 95, 60, 72
• heat to denature, cool so primers can bind, heat a little so taq polymerase works

Question 24

DNA hybridation

Answer 24

• measures DNA’s ability to hybridize with other organisms’ DNA strands
• higher degree of hybridation = higher relatedness
• heat DNA so it separates into single strands
• mix with fourescent probes that are for specific bacteria, like salmonella
• flourescent probe will bind to single DNA strand of salmonella and light up
• can use microarray to do a bunch of these at once

Question 25

cladogram

Answer 25

maps that show evolutionary relationships among organisms

-based on rRNA sequence