BIOL 240 MIDTERM 1 QUESTIONS &
ANSWERS|| 2025 LATEST UPDATE
What is microbiology? - ANSWERthe 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 - ANSWERMicroorganisms are archaea, eukaryotes, and
bacteria. Microbes include microorganisms as well as viruses
Classifying microbes - ANSWERwas a challenge historically because of the difficulties
in observing distinguishing characteristics of different categories.
Prokaryotic and Eukaryotic cells
Eukaryotic Macroorganisms - ANSWERanimals and plants
Eukaryotic Microorganisms - ANSWERfungi, protozoa, algae
Prokaryotic Macroorganisms - ANSWERNone known
Prokaryotic microorganisms - ANSWERBacteria and Archaea
Who was the first to see a microorganism? - ANSWERRobert Hooke
Who initially made improvements in lens construction of a microscope which allowed for
the first description of bacteria? - ANSWERAntoine Van Leeuwenhoek
What evolved from microorganisms? How? - ANSWERMulticellular organisms. Through
the biosphere they created
How much of the Earth's biomass is comprised of microorganisms? - ANSWERMore
than 50%
What are some examples of things that would happen if there were no microbes? -
ANSWERLeaves 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? - ANSWER- 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? - ANSWEREating,
reproducing, producing waste products, and surviving
What is the basis of life? - ANSWER- Metabolism
- Growth
- Reproduction
How are the 3 basis of life achieved? - ANSWER- genetic variation/evolution (mutation,
recombination, etc during meiosis)
- response/adaptation
- Homeostasis (maintaining internal organization and order, usually be expending
energy to do so)
Heterotroph - ANSWERorganism that obtains energy from the foods it consumes; also
called a consumer
Autotroph - ANSWERAn organism that makes its own organic molecules
Autotrophic metabolism started before heterotrophic
How are organic molecules broken down? - ANSWERThrough fermentation and aerobic
respiration
Why are organic molecules broken down? - ANSWERSo they can be used by microbes
to harness chemical energy (ATP)
Fermentation - ANSWERA 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 - ANSWERRespiration 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? - ANSWERThey interact with the
environment by cycling inorganic molecules to organic molecules and back
Macromolcules - ANSWERPolypeptides (proteins/amino acids), nucleic acids
(DNA/RNA), Lipids (fat), Polysaccharides (Carbohydrates/sugar)
Where does 90% of RNA come from? - ANSWERribosomes
Which macromolecule contains the most amount of dry weight of cell? -
ANSWERPolypeptides (50-55%)
Which macromolecule contains the least amount of dry weight of cell? - ANSWERDNA
(2-5%)
What is the dry weight % of RNA, Lipids, and Polysaccharides? - ANSWERRNA: 15-
20%
Lipids: 10%
Polysaccharides: 6-7%
Functions of amino acids - ANSWEREnzymes catalyze most biochemical reactions,
other proteins are structural components
Functions of DNA - ANSWERprovides the instructions for assembly and reproduction of
the cell
Functions of RNA - ANSWERInvolved in the production of polypeptides. Some have
structural or catalytic functions
Functions of Lipids - ANSWERMake 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 - ANSWERStructural (cellulose and chitin) and energy
storage (glycogen and starch)
The Phylogenic tree - ANSWERA 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? - ANSWEREukarya
Which domain does not contain histones? - ANSWERBacteria - have histone like
proteins
Which domain has a unique plasma membrane? - ANSWERArchaea
ANSWERS|| 2025 LATEST UPDATE
What is microbiology? - ANSWERthe 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 - ANSWERMicroorganisms are archaea, eukaryotes, and
bacteria. Microbes include microorganisms as well as viruses
Classifying microbes - ANSWERwas a challenge historically because of the difficulties
in observing distinguishing characteristics of different categories.
Prokaryotic and Eukaryotic cells
Eukaryotic Macroorganisms - ANSWERanimals and plants
Eukaryotic Microorganisms - ANSWERfungi, protozoa, algae
Prokaryotic Macroorganisms - ANSWERNone known
Prokaryotic microorganisms - ANSWERBacteria and Archaea
Who was the first to see a microorganism? - ANSWERRobert Hooke
Who initially made improvements in lens construction of a microscope which allowed for
the first description of bacteria? - ANSWERAntoine Van Leeuwenhoek
What evolved from microorganisms? How? - ANSWERMulticellular organisms. Through
the biosphere they created
How much of the Earth's biomass is comprised of microorganisms? - ANSWERMore
than 50%
What are some examples of things that would happen if there were no microbes? -
ANSWERLeaves 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? - ANSWER- 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? - ANSWEREating,
reproducing, producing waste products, and surviving
What is the basis of life? - ANSWER- Metabolism
- Growth
- Reproduction
How are the 3 basis of life achieved? - ANSWER- genetic variation/evolution (mutation,
recombination, etc during meiosis)
- response/adaptation
- Homeostasis (maintaining internal organization and order, usually be expending
energy to do so)
Heterotroph - ANSWERorganism that obtains energy from the foods it consumes; also
called a consumer
Autotroph - ANSWERAn organism that makes its own organic molecules
Autotrophic metabolism started before heterotrophic
How are organic molecules broken down? - ANSWERThrough fermentation and aerobic
respiration
Why are organic molecules broken down? - ANSWERSo they can be used by microbes
to harness chemical energy (ATP)
Fermentation - ANSWERA 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 - ANSWERRespiration 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? - ANSWERThey interact with the
environment by cycling inorganic molecules to organic molecules and back
Macromolcules - ANSWERPolypeptides (proteins/amino acids), nucleic acids
(DNA/RNA), Lipids (fat), Polysaccharides (Carbohydrates/sugar)
Where does 90% of RNA come from? - ANSWERribosomes
Which macromolecule contains the most amount of dry weight of cell? -
ANSWERPolypeptides (50-55%)
Which macromolecule contains the least amount of dry weight of cell? - ANSWERDNA
(2-5%)
What is the dry weight % of RNA, Lipids, and Polysaccharides? - ANSWERRNA: 15-
20%
Lipids: 10%
Polysaccharides: 6-7%
Functions of amino acids - ANSWEREnzymes catalyze most biochemical reactions,
other proteins are structural components
Functions of DNA - ANSWERprovides the instructions for assembly and reproduction of
the cell
Functions of RNA - ANSWERInvolved in the production of polypeptides. Some have
structural or catalytic functions
Functions of Lipids - ANSWERMake 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 - ANSWERStructural (cellulose and chitin) and energy
storage (glycogen and starch)
The Phylogenic tree - ANSWERA 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? - ANSWEREukarya
Which domain does not contain histones? - ANSWERBacteria - have histone like
proteins
Which domain has a unique plasma membrane? - ANSWERArchaea
