MBIO 3401 EXAM 3 NEWEST 2025 ACTUAL EXAM COMPLETE
QUESTIONS AND CORRECT DETAILED ANSWERS (VERIFIED ANSWERS)
|ALREADY GRADED A+|BRAND NEW!!
What are the fundamental conditions require to sustain life? -
Answer-1.essential elements
2.continual source of energy (sun)
3.temperature range permitting liquid water
What is another name for "evidence of early life?" -
Answer-biosignature
what are three biosignatures -
Answer-1. isotope ratios
2. stromatolites
3. microfossils
What are the models for the first cells? -
Answer-1. prebiotic soup
2. early oxidation-reduction reactions
3. RNA world
What is a stromatolite? -
Answer-layers deposits (cyanobacteria) formed by the growth of blue-green algae
What is prebiotic soup? -
Answer-blend of gases forming a broth when exposed to light or head then forming the
building blocks of life
How did organisms diverge from each other? -
Answer-1. random mutations
2. natural selection
3. reductive (degenerative) evolution
What is a molecular clock? -
Answer-method used by researchers that uses mutation rates in DNA to estimate the
length of time that two species have been evolving independently
what is the most widely used molecular clock? -
Answer-The gene encoding the small subunit rRNA (SSU rRNA)
what does DNA sequence alignment compare? -
Answer-the similarity and identity of amino acids and DNA
what are the three domains of life? -
Answer-Bacteria, Archaea, Eukarya
,What is the criteria for a working definition of a species -
Answer-1. SSU rRNA greater/equal to 95%
2. avg. nucleotide identity of ortholog genes greater/equal to 95%
3. shared ecotype between organisms greater/equal to 95%
, What is vertical gene transfer? -
Answer-transmission of genes from parent to offspring
What is horizontal gene transfer? -
Answer-acquisition of genes from another organism in the same generation
What is symbiosis? -
Answer-the intimate association of two species
What is mutualism? -
Answer-both organisms benefit
What is parasitism? -
Answer-One organism benefits and the other is harmed
When does endosymbiosis occur? -
Answer-when one partner grows within the body of another
Streptomyces -
Answer--linear chromosome with telomeres
-major antibiotic producer
-looks like mold but is bacteria
what is an example of actinomycetes? -
Answer-streptomycin
Mycobacterium -
Answer--thick
cell walls containing mycolic acids (mycomembrane)
-appears gram-negative because of tightly packed mycolic acid cell wall
what are some examples of mycobacterium -
Answer-M. Tuberculosis, M. Leprae
What are the gram positive bacteria? -
Answer-Actinomycetes and Nonmycelial actinobacteria
Proteobacteria -
Answer--triple layered cell envelope
-DIVERSE METABOLISM
what is photoheterotropy? -
Answer-able to switch metabolic pathways
Alphaproteobacteria -
Answer--Oligotroph- capable of living in low-nutrient environments such as deep oceanic
sediments, glacial ice, or deep undersurface soil
QUESTIONS AND CORRECT DETAILED ANSWERS (VERIFIED ANSWERS)
|ALREADY GRADED A+|BRAND NEW!!
What are the fundamental conditions require to sustain life? -
Answer-1.essential elements
2.continual source of energy (sun)
3.temperature range permitting liquid water
What is another name for "evidence of early life?" -
Answer-biosignature
what are three biosignatures -
Answer-1. isotope ratios
2. stromatolites
3. microfossils
What are the models for the first cells? -
Answer-1. prebiotic soup
2. early oxidation-reduction reactions
3. RNA world
What is a stromatolite? -
Answer-layers deposits (cyanobacteria) formed by the growth of blue-green algae
What is prebiotic soup? -
Answer-blend of gases forming a broth when exposed to light or head then forming the
building blocks of life
How did organisms diverge from each other? -
Answer-1. random mutations
2. natural selection
3. reductive (degenerative) evolution
What is a molecular clock? -
Answer-method used by researchers that uses mutation rates in DNA to estimate the
length of time that two species have been evolving independently
what is the most widely used molecular clock? -
Answer-The gene encoding the small subunit rRNA (SSU rRNA)
what does DNA sequence alignment compare? -
Answer-the similarity and identity of amino acids and DNA
what are the three domains of life? -
Answer-Bacteria, Archaea, Eukarya
,What is the criteria for a working definition of a species -
Answer-1. SSU rRNA greater/equal to 95%
2. avg. nucleotide identity of ortholog genes greater/equal to 95%
3. shared ecotype between organisms greater/equal to 95%
, What is vertical gene transfer? -
Answer-transmission of genes from parent to offspring
What is horizontal gene transfer? -
Answer-acquisition of genes from another organism in the same generation
What is symbiosis? -
Answer-the intimate association of two species
What is mutualism? -
Answer-both organisms benefit
What is parasitism? -
Answer-One organism benefits and the other is harmed
When does endosymbiosis occur? -
Answer-when one partner grows within the body of another
Streptomyces -
Answer--linear chromosome with telomeres
-major antibiotic producer
-looks like mold but is bacteria
what is an example of actinomycetes? -
Answer-streptomycin
Mycobacterium -
Answer--thick
cell walls containing mycolic acids (mycomembrane)
-appears gram-negative because of tightly packed mycolic acid cell wall
what are some examples of mycobacterium -
Answer-M. Tuberculosis, M. Leprae
What are the gram positive bacteria? -
Answer-Actinomycetes and Nonmycelial actinobacteria
Proteobacteria -
Answer--triple layered cell envelope
-DIVERSE METABOLISM
what is photoheterotropy? -
Answer-able to switch metabolic pathways
Alphaproteobacteria -
Answer--Oligotroph- capable of living in low-nutrient environments such as deep oceanic
sediments, glacial ice, or deep undersurface soil
