Portage Learning
1. Which of the following correctly lists the taxonomic hierarchy from most inclusive
to most specific?
A) Kingdom, Phylum, Class, Order, Family, Genus, Species
B) Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species
C) Domain, Phylum, Kingdom, Class, Order, Family, Genus, Species
D) Species, Genus, Family, Order, Class, Phylum, Kingdom, Domain
Correct Answer: Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species
Rationale: The correct taxonomic hierarchy from most inclusive to most specific is:
Domain → Kingdom → Phylum → Class → Order → Family → Genus → Species.
The addition of the Domain level, developed by Carl Woese, reflects evolutionary
relationships and includes the three domains: Bacteria, Archaea, and Eukarya.
2. A microbiology student observes a microorganism that lacks a true nucleus and
membrane-bound organelles. Under which domain should this organism be
classified?
A) Eukarya
B) Bacteria or Archaea
C) Protista
D) Fungi
Correct Answer: Bacteria or Archaea
Rationale: Organisms lacking a true nucleus and membrane-bound organelles are
prokaryotes. The two prokaryotic domains are Bacteria and Archaea. Domain
Eukarya contains all eukaryotes, which have a nucleus. Protista and Fungi are
kingdoms within Eukarya.
,3. A bacterial species name is correctly written as:
A) escherichia coli
B) Escherichia Coli
C) Escherichia coli
D) ESCHERICHIA COLI
Correct Answer: Escherichia coli
Rationale: Scientific names follow binomial nomenclature: the genus is capitalized,
the species is lowercase, and both are italicized (or underlined when handwritten).
Therefore, Escherichia coli is correct. After first use, the genus is abbreviated to its
first initial followed by a period, e.g., E. coli.
4. Which of the following characteristics distinguishes Archaea from Bacteria?
A) Presence of a cell wall
B) Unicellular organization
C) Lack of membrane-bound organelles
D) Ether-linked membrane lipids and absence of peptidoglycan
Correct Answer: Ether-linked membrane lipids and absence of peptidoglycan
Rationale: Both Bacteria and Archaea are unicellular prokaryotes that lack
membrane-bound organelles and often have cell walls. However, Archaea are
distinguished by having ether-linked membrane lipids and lacking peptidoglycan in
their cell walls (they may have pseudomurein). Bacteria have ester-linked lipids and
peptidoglycan.
5. True or False: A virus is classified as a microbe.
A) True
B) False
Correct Answer: True
,Rationale: While viruses are not living and are not considered microorganisms, they
are classified under the broader term "microbes," which includes both
microorganisms (cellular organisms) and viruses (acellular entities). This distinction
is crucial for understanding the scope of microbiology.
6. True or False: A virus is considered a microorganism.
A) True
B) False
Correct Answer: False
Rationale: Viruses are not living organisms and therefore are not considered
microorganisms. They lack cellular structure, cannot replicate independently, and do
not carry out metabolic processes. They are acellular (lacking cells) and must
replicate within a host.
7. What is the smallest biological unit of life?
A) The molecule
B) The atom
C) The cell
D) The tissue
Correct Answer: The cell
Rationale: The cell is the fundamental structural and functional unit of all living
organisms. It is the smallest entity that can carry out all life processes independently.
Molecules and atoms are chemical building blocks but are not alive.
8. Which of the following are the four main types of macromolecules?
A) Carbohydrates, Proteins, Nucleic Acids, and Lipids
B) Carbohydrates, Proteins, Nucleic Acids, and Minerals
, C) Proteins, Lipids, Vitamins, and Nucleic Acids
D) Carbohydrates, Lipids, Proteins, and Water
Correct Answer: Carbohydrates, Proteins, Nucleic Acids, and Lipids
Rationale: The four main macromolecules are carbohydrates, proteins, nucleic
acids, and lipids. These organic molecules are essential for all life forms, serving as
energy sources, structural components, genetic material, and more.
9. What is the primary difference between prokaryotic and eukaryotic cells?
A) The presence of a cell wall
B) The presence or absence of a true, membrane-bound nucleus
C) The presence of ribosomes
D) The ability to perform metabolism
Correct Answer: The presence or absence of a true, membrane-bound nucleus
Rationale: The primary difference between prokaryotic and eukaryotic cells is the
presence (in eukaryotes) or absence (in prokaryotes) of a true, membrane-bound
nucleus. Prokaryotes lack membrane-bound organelles, while eukaryotes possess
them.
10. Which of the following is NOT a characteristic of a prokaryotic cell?
A) Lack of a nucleus
B) Lack of membrane-bound organelles
C) Presence of a cell wall
D) Presence of membrane-bound organelles
Correct Answer: Presence of membrane-bound organelles