MBIO 3401 TTU Exam 3 Exam
Questions & Answers (Grade A+)
What is the metagenome? -
correct answer ✅The sum total of all DNA in an environmental
sample.
What is the small subunit (SSU) rRNA sequence? -
correct answer ✅The standard for identifying environmental taxa.
How are microbes identified? -
correct answer ✅Compare SSU rRNA
What is the SSU rRNA for prokayotes? -
correct answer ✅16S rRNA
What is the SSU rRNA for eukaryotes? -
correct answer ✅18S rRNA
What are operational taxonomic units (OTUs)? -
correct answer ✅A working metagenomic definition of "species"
What is a rarefaction curve? -
correct answer ✅Plots out the OTUs (species) as a function of
increasing sample size.
,MBIO 3401 TTU Exam 3 Exam
Questions & Answers (Grade A+)
Ending "-ales" of bacteria typically indicates... -
correct answer ✅Bacterial order
What are the loop sites on bacterial 16S rRNA? -
correct answer ✅Sites that are free to mutate and evolve faster.
What are the stem sites on bacterial 16S rRNA? -
correct answer ✅Sites that rarely mutate and are conserved.
What are deep-branching thermophiles? -
correct answer ✅Bacteria that diverged earliest from ancestral
archaea.
Fastest doubling rates of all cells.
High mutation rate.
What are the deep-branching thermophiles? -
correct answer ✅Chloroflexi
Deinococcus-Thermus
,MBIO 3401 TTU Exam 3 Exam
Questions & Answers (Grade A+)
Chloroflexi: -
correct answer ✅Photoheterotrophic, moderate thermophile
Green nonsulfur bacteria
Contain chlorosomes
Forms filamentous mats with cyanobacteria.
Deinococcus-Thermus (phylum) -
correct answer ✅Contain ornithine (amino acid) in peptidoglycan
cross-bridges.
Thermus (species) -
correct answer ✅Moderate thermophiles
Heterotrophs
Deinococcus (species) -
correct answer ✅Not thermophilic
Resistant to high radiation/desiccation
Thick cell wall and S-layer
What are cyanobacteria? -
correct answer ✅Only oxygenic phototrophic prokaryotes.
, MBIO 3401 TTU Exam 3 Exam
Questions & Answers (Grade A+)
(contain chlorophyll/pigments)
Photosynthesis in the thylakoids
Fix CO2 in carboxysomes
Float with gas vesicles
Fix N2 in heterocysts
What are the phylum of Gram +? -
correct answer ✅Firmicutes (low GC) and Actinobacteria (high GC)
Contain thick cell walls, reinforced by teichoic acids.
What are the spore-forming firmicutes? -
correct answer ✅Bacillus and Clostridium
Questions & Answers (Grade A+)
What is the metagenome? -
correct answer ✅The sum total of all DNA in an environmental
sample.
What is the small subunit (SSU) rRNA sequence? -
correct answer ✅The standard for identifying environmental taxa.
How are microbes identified? -
correct answer ✅Compare SSU rRNA
What is the SSU rRNA for prokayotes? -
correct answer ✅16S rRNA
What is the SSU rRNA for eukaryotes? -
correct answer ✅18S rRNA
What are operational taxonomic units (OTUs)? -
correct answer ✅A working metagenomic definition of "species"
What is a rarefaction curve? -
correct answer ✅Plots out the OTUs (species) as a function of
increasing sample size.
,MBIO 3401 TTU Exam 3 Exam
Questions & Answers (Grade A+)
Ending "-ales" of bacteria typically indicates... -
correct answer ✅Bacterial order
What are the loop sites on bacterial 16S rRNA? -
correct answer ✅Sites that are free to mutate and evolve faster.
What are the stem sites on bacterial 16S rRNA? -
correct answer ✅Sites that rarely mutate and are conserved.
What are deep-branching thermophiles? -
correct answer ✅Bacteria that diverged earliest from ancestral
archaea.
Fastest doubling rates of all cells.
High mutation rate.
What are the deep-branching thermophiles? -
correct answer ✅Chloroflexi
Deinococcus-Thermus
,MBIO 3401 TTU Exam 3 Exam
Questions & Answers (Grade A+)
Chloroflexi: -
correct answer ✅Photoheterotrophic, moderate thermophile
Green nonsulfur bacteria
Contain chlorosomes
Forms filamentous mats with cyanobacteria.
Deinococcus-Thermus (phylum) -
correct answer ✅Contain ornithine (amino acid) in peptidoglycan
cross-bridges.
Thermus (species) -
correct answer ✅Moderate thermophiles
Heterotrophs
Deinococcus (species) -
correct answer ✅Not thermophilic
Resistant to high radiation/desiccation
Thick cell wall and S-layer
What are cyanobacteria? -
correct answer ✅Only oxygenic phototrophic prokaryotes.
, MBIO 3401 TTU Exam 3 Exam
Questions & Answers (Grade A+)
(contain chlorophyll/pigments)
Photosynthesis in the thylakoids
Fix CO2 in carboxysomes
Float with gas vesicles
Fix N2 in heterocysts
What are the phylum of Gram +? -
correct answer ✅Firmicutes (low GC) and Actinobacteria (high GC)
Contain thick cell walls, reinforced by teichoic acids.
What are the spore-forming firmicutes? -
correct answer ✅Bacillus and Clostridium
