MCB 3020C Microbiology EXAM 1 Questions
and Answers (Graded A)
What are the two types of microbial cells? - ANSWER - Prokaryotic and eukaryotic
What is the 3 domains that are based on the comparison of rRNA? - ANSWER - -Bacteria
-Archaea
-Eukarya
B.A.E.
Domain Bacteria - ANSWER - Has:
-peptidoglycan
-can have plasmids
-Can perform Horizontal Gene transfer (HGT)
-Beta (1,4) Glycosidic
-Hopanoids
-Nucleoid
-Can be Gram (+) or (-)
-Lacks a membrane-bound nucleus
Domain Archaea - ANSWER - Has:
-Unique rRNA
-Can have monolayer or bilayer plasma membrane
-Pseudomurein in cell wall
,-All have L-peptides
-Methanogenesis
-Hami = Hook
-Canulae
-could just have S-layer
-Beta (1,3) Glycosidic
-Lack peptidoglycan
-unique lipids
Domain Eukarya - ANSWER - Consists of Protists and Fungi:
*Generally larger than prokaryotes
Protists: W.A.S.P.
-Water Molds
-Algae
-Slime Molds
-Protozoa
Fungi:
*Macro & microorganisms
-Yeast=Unicellular
-Molds=Multicellular
SSU rRNA - ANSWER - small subunit ribosomal RNA
,-sequences of 16s &18s rRNA
What is the universal phylogenetic tree based off of? - ANSWER - -based on comparisons of SSU rRNA
(Small subunit rRNA)
-provides relatedness, but not time of divergence.
Which two domains evolved independently of the other domain? - ANSWER - Archaea & Eukarya
evolved independently of Bacteria
Which two domains diverged from a common ancestor? - ANSWER - Archaea &Eukarya
When comparing rRNA sequences between two organisms, their relatedness is represented by...? -
ANSWER - Percent Sequence Homology
-70% is cutoff value for species definition
Viruses - ANSWER - -Smallest of all microbes
-Requires host to replicate
-NON-LIVING
-causes range of disease, some cancers
-Virions is the complete virus
-transfers gene between bacteria and others
What are viroids and virusoids? - ANSWER - infectious agents composed of RNA
Prions - ANSWER - infectious proteins
-Proteinaceous infectious particles
, - causes a variety of degenerative diseases
a)scrapie in sheep
b)Bovine spongiform Encephalopathy (BSE) or mad cow disease
c)Cruetzfeldt-jakob disease (CJD)
d)Kuru in humans
Definition of life: - ANSWER - -cells and organization
-response to environmental changes
-growth and development
-biological evolution
-energy use and metabolism
-regulation and homeostasis
-reproduction
LUCA - ANSWER - last universal common ancestor
Endosymbiotic Hypothesis - ANSWER - origin of mitochondria, chloroplasts, and hydrogenosomes from
endosymbiont
Steps in Endosymbiotic Hypothesis - ANSWER - -Ancestral Eukaryotic cell had lost cell wall
-Engulfment of an endosymbiont occurred
-Produced needed product such as ATP.
-Genome reduction occurs
What led to selected traits? - ANSWER - Mutations of genetic material.
Mosaic of Genetic Info - ANSWER - The new genes & genotypes that evolved
and Answers (Graded A)
What are the two types of microbial cells? - ANSWER - Prokaryotic and eukaryotic
What is the 3 domains that are based on the comparison of rRNA? - ANSWER - -Bacteria
-Archaea
-Eukarya
B.A.E.
Domain Bacteria - ANSWER - Has:
-peptidoglycan
-can have plasmids
-Can perform Horizontal Gene transfer (HGT)
-Beta (1,4) Glycosidic
-Hopanoids
-Nucleoid
-Can be Gram (+) or (-)
-Lacks a membrane-bound nucleus
Domain Archaea - ANSWER - Has:
-Unique rRNA
-Can have monolayer or bilayer plasma membrane
-Pseudomurein in cell wall
,-All have L-peptides
-Methanogenesis
-Hami = Hook
-Canulae
-could just have S-layer
-Beta (1,3) Glycosidic
-Lack peptidoglycan
-unique lipids
Domain Eukarya - ANSWER - Consists of Protists and Fungi:
*Generally larger than prokaryotes
Protists: W.A.S.P.
-Water Molds
-Algae
-Slime Molds
-Protozoa
Fungi:
*Macro & microorganisms
-Yeast=Unicellular
-Molds=Multicellular
SSU rRNA - ANSWER - small subunit ribosomal RNA
,-sequences of 16s &18s rRNA
What is the universal phylogenetic tree based off of? - ANSWER - -based on comparisons of SSU rRNA
(Small subunit rRNA)
-provides relatedness, but not time of divergence.
Which two domains evolved independently of the other domain? - ANSWER - Archaea & Eukarya
evolved independently of Bacteria
Which two domains diverged from a common ancestor? - ANSWER - Archaea &Eukarya
When comparing rRNA sequences between two organisms, their relatedness is represented by...? -
ANSWER - Percent Sequence Homology
-70% is cutoff value for species definition
Viruses - ANSWER - -Smallest of all microbes
-Requires host to replicate
-NON-LIVING
-causes range of disease, some cancers
-Virions is the complete virus
-transfers gene between bacteria and others
What are viroids and virusoids? - ANSWER - infectious agents composed of RNA
Prions - ANSWER - infectious proteins
-Proteinaceous infectious particles
, - causes a variety of degenerative diseases
a)scrapie in sheep
b)Bovine spongiform Encephalopathy (BSE) or mad cow disease
c)Cruetzfeldt-jakob disease (CJD)
d)Kuru in humans
Definition of life: - ANSWER - -cells and organization
-response to environmental changes
-growth and development
-biological evolution
-energy use and metabolism
-regulation and homeostasis
-reproduction
LUCA - ANSWER - last universal common ancestor
Endosymbiotic Hypothesis - ANSWER - origin of mitochondria, chloroplasts, and hydrogenosomes from
endosymbiont
Steps in Endosymbiotic Hypothesis - ANSWER - -Ancestral Eukaryotic cell had lost cell wall
-Engulfment of an endosymbiont occurred
-Produced needed product such as ATP.
-Genome reduction occurs
What led to selected traits? - ANSWER - Mutations of genetic material.
Mosaic of Genetic Info - ANSWER - The new genes & genotypes that evolved
