Quizes Review Flashcards
A population of frogs that gets separated into two groups by the formation of a natural dam eventually become two distinct species. This process by which this occurs is called
Allopatric speciation
A population of a moth species is introduced to a new area. Over time different members of this population specialize too distinct roles in the habitats. Over time, the varied demands of their new lifestyles lead to multiple speciation events originating from a single species. This is an example of
Adaptive radiation
Small circles of DNA called ____ exist in addition to the bacterial chromosomes
Plasmids
Penicillin works most effectively against gram-positive bacteria because
They have a thick peptidoglycan cell wall & penicillin affects the synthesis to peptidoglycans.
The placement of prokaryotes into major clades within the domains within the domains Archaea and Bacteria has been based on ___.
Molecular comparisons
A gram stain distinguishes bacteria based on a difference in
Cell walls
What shape is prokaryote cells?
Cocci (circular), spherical, long
What’s true in all prokaryotes (bacteria and archaea)
They are unicellular
Chemoautotrophs use _____.
Inorganic chemicals such as H2S as a carbon source.
Photoautotrophs use ______.
light as an energy and organic compounds (not atmospheric CO2) as a carbon source.
What’s not a source of genetic variation in bacterial population?
Mutation
___ is a form of genetic exchange in bacteria that involves contact between two cells.
conjugation
small circles of DNA called __ exist in addition to the bacterial chromosomes.
plasmids
Penicillin works most effectively against gram-pos bacteria because…..
They have a thick peptidoglycan cell wall & penicillin affects the synthesis of peptidoglycans.
The placement of prokaryotes into major clades within the domains Archaea & Bacteria has been based on ___.
Molecular Comparisons
bacterium associated with soil nitrification
Nitrosomonas
common bacterium used in biological research
Escherichia coli (E.Coli)
this bacterium is known to cause stomach ulcers.
Helicobacter pylori
This clade of bacteria is parasitic & can only live within animal host cells.
Chlamydias
These bacteria are gram-neg & generate
