Microbiology 3050 Exam 1 Questions
with Latest Update
Microorganism - Answer-Organisms and acellular entities too small to be seen clearly
by an unaided eye;
=<1mm in diameter
often unicellular
Cellular - Answer-Fungi (yeasts + molds)
protists (algae, protozoa, slime molds)
bacteria (E. coli)
Archaea (methanogens)
Acellular - Answer-Viruses (protein + nucleic acids)
Viroids (RNA)
Satellites (Nucleic Acid + RNA)
Prions (infections proteins)
Importance of Microorganisms - Answer-most populous group of organisms
1.3:1 cells:bacteria ratio
50% of earths carbon is from microbes
90% of earths nitrogen is from bacteria
75% of earths oxygen is from algae
we can only culture less than 1% of earths bacterias
Prokaryotic - Answer-lack true membrane-bound nucleus; not absolute
cytoplasm with ribosomes
nucleoid region contains DNA
plasmid contains advantageous "traited" DNA
cytoplasmic membrane
cell wall
Eukaryotic - Answer-possess membrane-bound nucleus
other membrane-bound organelles
usually more complex than prokaryotes
usually larger than prokaryotes
chloroplast
mitochondria
etc.
Universal Phylogenetic Tree - Answer-a. isolate DNA
b. make copies of rRNA by PCR-polymerase chain reactions
c. Sequence DNA
d. Analyze sequence by pairing mismatches in the rRNA
, e. (# of unmatched) / (total genes) * 100% = % evolutionary distance
LUCA - Answer-all three branches of come from LUCA-the Last Universal Common
Ancestor
1. Bacteria
2. Archaea
3. Eukarya
Endo-symbiotic Hypothesis - Answer-Eukaryotic cells potentially came about from the
symbiosis of separate single-celled organisms forming several key organelles.
side notes:
1. Eukarya and bacteria evolved separately
2. Tree of life is very complex; always changing
Bacteria - Answer-PROKARYOTES
usually single-celled
majority have cell wall with PEPTIDOGLYCAN
in soil, water, air, in/on other organisms
some live in extreme enviornments
can cause disease in humans
do not have cell membrane with lipids
proteobacteria, mitochondrion, gram-positive bacteria cyanobacteria, chloroplasts,
hyperthermophiles
Archaea - Answer-PROKARYOTES
usually single-celled
Distinct SSU RNA sequences (grouping archea from bacteria based on difference)
no peptidoglycan
do not cause disease in humans
have cell membrane with lipids
some have unusual metabolic characteristics; methanogens make methane
MANY LIVE IN EXTREME ENVIRONMENTS
Crenarchaeota, Euryarchaeota, Methanogens, Extreme halophiles
Eukarya - Answer-EUKARYOTES
Protists-typically unicellular, but generally larger than members of Bacteria and Archaea
-Algae, protozoa, slime molds, and water molds
Fungi-unicellular to multicellular
-yeast
-molds+mildews: Hypha-filaments stretch and search for nutrients for growth-thats why
you can see molds+mildews
-mushrooms: kind of, not really accepted to be a full on microorganism due to their size
Animals, Fungi, Plants, Flagellates, Slime molds, etc.
with Latest Update
Microorganism - Answer-Organisms and acellular entities too small to be seen clearly
by an unaided eye;
=<1mm in diameter
often unicellular
Cellular - Answer-Fungi (yeasts + molds)
protists (algae, protozoa, slime molds)
bacteria (E. coli)
Archaea (methanogens)
Acellular - Answer-Viruses (protein + nucleic acids)
Viroids (RNA)
Satellites (Nucleic Acid + RNA)
Prions (infections proteins)
Importance of Microorganisms - Answer-most populous group of organisms
1.3:1 cells:bacteria ratio
50% of earths carbon is from microbes
90% of earths nitrogen is from bacteria
75% of earths oxygen is from algae
we can only culture less than 1% of earths bacterias
Prokaryotic - Answer-lack true membrane-bound nucleus; not absolute
cytoplasm with ribosomes
nucleoid region contains DNA
plasmid contains advantageous "traited" DNA
cytoplasmic membrane
cell wall
Eukaryotic - Answer-possess membrane-bound nucleus
other membrane-bound organelles
usually more complex than prokaryotes
usually larger than prokaryotes
chloroplast
mitochondria
etc.
Universal Phylogenetic Tree - Answer-a. isolate DNA
b. make copies of rRNA by PCR-polymerase chain reactions
c. Sequence DNA
d. Analyze sequence by pairing mismatches in the rRNA
, e. (# of unmatched) / (total genes) * 100% = % evolutionary distance
LUCA - Answer-all three branches of come from LUCA-the Last Universal Common
Ancestor
1. Bacteria
2. Archaea
3. Eukarya
Endo-symbiotic Hypothesis - Answer-Eukaryotic cells potentially came about from the
symbiosis of separate single-celled organisms forming several key organelles.
side notes:
1. Eukarya and bacteria evolved separately
2. Tree of life is very complex; always changing
Bacteria - Answer-PROKARYOTES
usually single-celled
majority have cell wall with PEPTIDOGLYCAN
in soil, water, air, in/on other organisms
some live in extreme enviornments
can cause disease in humans
do not have cell membrane with lipids
proteobacteria, mitochondrion, gram-positive bacteria cyanobacteria, chloroplasts,
hyperthermophiles
Archaea - Answer-PROKARYOTES
usually single-celled
Distinct SSU RNA sequences (grouping archea from bacteria based on difference)
no peptidoglycan
do not cause disease in humans
have cell membrane with lipids
some have unusual metabolic characteristics; methanogens make methane
MANY LIVE IN EXTREME ENVIRONMENTS
Crenarchaeota, Euryarchaeota, Methanogens, Extreme halophiles
Eukarya - Answer-EUKARYOTES
Protists-typically unicellular, but generally larger than members of Bacteria and Archaea
-Algae, protozoa, slime molds, and water molds
Fungi-unicellular to multicellular
-yeast
-molds+mildews: Hypha-filaments stretch and search for nutrients for growth-thats why
you can see molds+mildews
-mushrooms: kind of, not really accepted to be a full on microorganism due to their size
Animals, Fungi, Plants, Flagellates, Slime molds, etc.
