BIOL 240 Midterm 1 || A+ GRADED SOLUTIONS.
What is microbiology? correct answers the study of microbes, examines how they interact
with humans&food as well as how they can be used by humans
basis for molecular biology and biotechnology
Microbes vs Microorganisms correct answers Microorganisms are archaea, eukaryotes, and
bacteria. Microbes include microorganisms as well as viruses
Classifying microbes correct answers was a challenge historically because of the difficulties
in observing distinguishing characteristics of different categories.
Prokaryotic and Eukaryotic cells
Eukaryotic Macroorganisms correct answers animals and plants
Eukaryotic Microorganisms correct answers fungi, protozoa, algae
Prokaryotic Macroorganisms correct answers None known
Prokaryotic microorganisms correct answers Bacteria and Archaea
Who was the first to see a microorganism? correct answers Robert Hooke
Who initially made improvements in lens construction of a microscope which allowed for the
first description of bacteria? correct answers Antoine Van Leeuwenhoek
What evolved from microorganisms? How? correct answers Multicellular organisms.
Through the biosphere they created
How much of the Earth's biomass is comprised of microorganisms? correct answers More
than 50%
What are some examples of things that would happen if there were no microbes? correct
answers Leaves would fall, crops would die, things would smell different, food would rot,
oxygen would eventually run out, no wine/beer/bread/etc, and there would be no diseases
Why should we study microbiology? correct answers - Our understanding of life has arisen
largely from studies of microorganisms despite us still not knowing much about them.
-Easy to study because they're easy to grow and are cheap. Also because most of them have a
small number of genes. Genetic manipulation is easy to do. They also produce enzymes and
other molecules for industrial and medical uses.
Ex: Studying the genetics of microbes can benefit humans, like the mass production of
molecules
What are microorganisms in soils, water, and our body doing? correct answers Eating,
reproducing, producing waste products, and surviving
,What is the basis of life? correct answers - Metabolism
- Growth
- Reproduction
How are the 3 basis of life achieved? correct answers - genetic variation/evolution (mutation,
recombination, etc during meiosis)
- response/adaptation
- Homeostasis (maintaining internal organization and order, usually be expending energy to
do so)
Heterotroph correct answers organism that obtains energy from the foods it consumes; also
called a consumer
Autotroph correct answers An organism that makes its own organic molecules
Autotrophic metabolism started before heterotrophic
How are organic molecules broken down? correct answers Through fermentation and aerobic
respiration
Why are organic molecules broken down? correct answers So they can be used by microbes
to harness chemical energy (ATP)
Fermentation correct answers A catabolic process that makes a limited amount of ATP from
glucose without an electron transport chain and that produces a characteristic end product,
such as ethyl alcohol + CO2 or lactic acid.
Process by which cells release energy in the absence of oxygen
aerobic respiration correct answers Respiration that requires oxygen and forms up to 36 ATP
in the end.
glucose + oxygen -> CO2 + H2O
Glycolysis -> Acetyl CoA -> Krebs cycle -> Chemiosmosis
How can microbes help in biogeochemical cycling? correct answers They interact with the
environment by cycling inorganic molecules to organic molecules and back
Macromolcules correct answers Polypeptides (proteins/amino acids), nucleic acids
(DNA/RNA), Lipids (fat), Polysaccharides (Carbohydrates/sugar)
Where does 90% of RNA come from? correct answers ribosomes
Which macromolecule contains the most amount of dry weight of cell? correct answers
Polypeptides (50-55%)
Which macromolecule contains the least amount of dry weight of cell? correct answers DNA
(2-5%)
, What is the dry weight % of RNA, Lipids, and Polysaccharides? correct answers RNA: 15-
20%
Lipids: 10%
Polysaccharides: 6-7%
Functions of amino acids correct answers Enzymes catalyze most biochemical reactions,
other proteins are structural components
Functions of DNA correct answers provides the instructions for assembly and reproduction of
the cell
Functions of RNA correct answers Involved in the production of polypeptides. Some have
structural or catalytic functions
Functions of Lipids correct answers Make up cell membranes that form physical boundary
between the inside of the cell and surroundings as well as membranes of internal organelles
Functions of Polysaccharides correct answers Structural (cellulose and chitin) and energy
storage (glycogen and starch)
The Phylogenic tree correct answers A branching diagram that represents a hypothesis about
the evolutionary history of a group of organisms. Based on rRNA sequences.
Divided into three domains: Bacteria, archaea, eukarya
Which domain contains a nuclear membrane? correct answers Eukarya
Which domain does not contain histones? correct answers Bacteria - have histone like
proteins
Which domain has a unique plasma membrane? correct answers Archaea
Eukarya and Bacteria have similar plasma membranes
Which domain has 3 main polymerases? correct answers Eukarya
Bacteria and Archaea have a single polymerase. Archaea have Eukaryal-like RNA pol II
Which domain contains membrane bound organelles? correct answers Eukarya
Bacteria and Archaea rarely have them and they would be found in a few species
What does the cell wall in bacteria look like? correct answers Found in nearly all species and
is constructed of peptidoglycan
What does the cell wall in archaea look like? correct answers Found in nearly all species and
is constructed of various materials
What does the cell wall in eukarya look like? correct answers Found in some species and is
constructed of various materials
What is microbiology? correct answers the study of microbes, examines how they interact
with humans&food as well as how they can be used by humans
basis for molecular biology and biotechnology
Microbes vs Microorganisms correct answers Microorganisms are archaea, eukaryotes, and
bacteria. Microbes include microorganisms as well as viruses
Classifying microbes correct answers was a challenge historically because of the difficulties
in observing distinguishing characteristics of different categories.
Prokaryotic and Eukaryotic cells
Eukaryotic Macroorganisms correct answers animals and plants
Eukaryotic Microorganisms correct answers fungi, protozoa, algae
Prokaryotic Macroorganisms correct answers None known
Prokaryotic microorganisms correct answers Bacteria and Archaea
Who was the first to see a microorganism? correct answers Robert Hooke
Who initially made improvements in lens construction of a microscope which allowed for the
first description of bacteria? correct answers Antoine Van Leeuwenhoek
What evolved from microorganisms? How? correct answers Multicellular organisms.
Through the biosphere they created
How much of the Earth's biomass is comprised of microorganisms? correct answers More
than 50%
What are some examples of things that would happen if there were no microbes? correct
answers Leaves would fall, crops would die, things would smell different, food would rot,
oxygen would eventually run out, no wine/beer/bread/etc, and there would be no diseases
Why should we study microbiology? correct answers - Our understanding of life has arisen
largely from studies of microorganisms despite us still not knowing much about them.
-Easy to study because they're easy to grow and are cheap. Also because most of them have a
small number of genes. Genetic manipulation is easy to do. They also produce enzymes and
other molecules for industrial and medical uses.
Ex: Studying the genetics of microbes can benefit humans, like the mass production of
molecules
What are microorganisms in soils, water, and our body doing? correct answers Eating,
reproducing, producing waste products, and surviving
,What is the basis of life? correct answers - Metabolism
- Growth
- Reproduction
How are the 3 basis of life achieved? correct answers - genetic variation/evolution (mutation,
recombination, etc during meiosis)
- response/adaptation
- Homeostasis (maintaining internal organization and order, usually be expending energy to
do so)
Heterotroph correct answers organism that obtains energy from the foods it consumes; also
called a consumer
Autotroph correct answers An organism that makes its own organic molecules
Autotrophic metabolism started before heterotrophic
How are organic molecules broken down? correct answers Through fermentation and aerobic
respiration
Why are organic molecules broken down? correct answers So they can be used by microbes
to harness chemical energy (ATP)
Fermentation correct answers A catabolic process that makes a limited amount of ATP from
glucose without an electron transport chain and that produces a characteristic end product,
such as ethyl alcohol + CO2 or lactic acid.
Process by which cells release energy in the absence of oxygen
aerobic respiration correct answers Respiration that requires oxygen and forms up to 36 ATP
in the end.
glucose + oxygen -> CO2 + H2O
Glycolysis -> Acetyl CoA -> Krebs cycle -> Chemiosmosis
How can microbes help in biogeochemical cycling? correct answers They interact with the
environment by cycling inorganic molecules to organic molecules and back
Macromolcules correct answers Polypeptides (proteins/amino acids), nucleic acids
(DNA/RNA), Lipids (fat), Polysaccharides (Carbohydrates/sugar)
Where does 90% of RNA come from? correct answers ribosomes
Which macromolecule contains the most amount of dry weight of cell? correct answers
Polypeptides (50-55%)
Which macromolecule contains the least amount of dry weight of cell? correct answers DNA
(2-5%)
, What is the dry weight % of RNA, Lipids, and Polysaccharides? correct answers RNA: 15-
20%
Lipids: 10%
Polysaccharides: 6-7%
Functions of amino acids correct answers Enzymes catalyze most biochemical reactions,
other proteins are structural components
Functions of DNA correct answers provides the instructions for assembly and reproduction of
the cell
Functions of RNA correct answers Involved in the production of polypeptides. Some have
structural or catalytic functions
Functions of Lipids correct answers Make up cell membranes that form physical boundary
between the inside of the cell and surroundings as well as membranes of internal organelles
Functions of Polysaccharides correct answers Structural (cellulose and chitin) and energy
storage (glycogen and starch)
The Phylogenic tree correct answers A branching diagram that represents a hypothesis about
the evolutionary history of a group of organisms. Based on rRNA sequences.
Divided into three domains: Bacteria, archaea, eukarya
Which domain contains a nuclear membrane? correct answers Eukarya
Which domain does not contain histones? correct answers Bacteria - have histone like
proteins
Which domain has a unique plasma membrane? correct answers Archaea
Eukarya and Bacteria have similar plasma membranes
Which domain has 3 main polymerases? correct answers Eukarya
Bacteria and Archaea have a single polymerase. Archaea have Eukaryal-like RNA pol II
Which domain contains membrane bound organelles? correct answers Eukarya
Bacteria and Archaea rarely have them and they would be found in a few species
What does the cell wall in bacteria look like? correct answers Found in nearly all species and
is constructed of peptidoglycan
What does the cell wall in archaea look like? correct answers Found in nearly all species and
is constructed of various materials
What does the cell wall in eukarya look like? correct answers Found in some species and is
constructed of various materials
