Biology 121 Exam 1 UPDATED ACTUAL
Exam Questions and CORRECT Answers
What is the definition of Phylogeny? - CORRECT ANSWER - The evolutionary history of
a species or group of species
What is the definition of Systematics? - CORRECT ANSWER - A discipline focused on
classifying organisms and determining their evolutionary relationships
What is the definition of Taxonomy? - CORRECT ANSWER - A scientific discipline
concerned with naming & classifying the diverse forms of life
What do you know about Binomial Nomenclature? - CORRECT ANSWER - - Invented
by Carolus Linneaus
- It is a 2 part naming system comprised of the Genus (to which the species belongs; first part of
the binomial) and species (specific epithet, species within the genus, second part of binomial)
What do you know about Hierarchical Classification? - CORRECT ANSWER --
Hierarchy of increasingly inclusive categories
- Domain -> Kingdom -> Phylum -> Class -> Order -> Family -> Genus -> Species
- Taxon - the named taxonomic unit at any level of the hierarchy
How is phylogeny reconstructed using morphological characteristics? - CORRECT
ANSWER - Ancestral - a characteristic that originated in an ancestor of the taxon
Derived - an evolutionary novelty unique to a clade
What is the definition of Monophyletic? - CORRECT ANSWER - (Single Tribe) Consists
of an ancestral species and all of its descendants
What is the definition of Paraphyletic? - CORRECT ANSWER - (Beside the tribe)
Consists of an ancestral species & some but not all of its descendants
,What is the definition of Polyphyletic? - CORRECT ANSWER - (Many tribes) Includes
taxa with different ancestors
What is the history of Taxonomy? - CORRECT ANSWER - 1. Two Kingdoms - Animals
and Plants
*Early taxonomists classified all organisms into two kingdoms: plants and anaimals. Even
though they do not do photosynthesis (not photoautotrophic), fungi and bacteria were classified
as plants because they all have cell walls (although Bacteria and Fungi cell walls are quite
different from plant cell walls) Eukaryotic unicellular organisms with chloroplasts (which are
photoautotrophic) were placed in the plant kingdom. Eukaryotic unicellular organismss that
moved and ingested food (heterotrophic ingestive) were classified as animals. Organisms that
moved and were photosynthetic were a problem and claimed by both groups.
2. Five Kingdoms - Robert Whittaker 1969
Prokaryotic: Monera (lack membrane enclosed nucleus and organelles, Bacteria)
Eukaryotic: Protista (single-celled protists -> Algae, catch all), Fungi, Animalia, Plantae
*Despite its problems, the two kingdom system was not replaced until the late 1960's when Dr.
Robert H. Whittaker from Cornell University argued for a 5 kingdom system. Whittaker
recognized two fundamentally different types of cells, prokaryotic and eukaryotic. He named the
prokaryotes (bacteria) Kingdom Monera. He kept the plant kingdom for eukaryotic multicellular
photoautotrophic organisms and the animal kingdom for eukaryotic multicellular heterotrophic
ingestive organisms. He introduced the new Kingdom Fungi for multicellular heterotrophic
absorptive organisms. The remaining eukaryotic organisms, which did not fit into animal, plant,
or fungi kingdoms, were placed in the fifth kingdom, Protista. These organisms were mostly
single celled, but included the multicellular red, green, and brown algae. In general they are
"mixotrophs" which means that some are autotrophic and some heterotrophic.
3. Three Domain System - Eukarya, Archaea, Bacteria
Each c
How were Archaea/Bacteria separated? - CORRECT ANSWER - Archaea does not have
peptidoglycan while Bacteria does
What is the definition of Phylogenetic trees? - CORRECT ANSWER - Branching "trees"
that depict evolutionary relationships
,How is phylogeny reconstructed using molecular methods? - CORRECT ANSWER --
Based on molecular sequence of DNA
- Bacteria/Archaea Classification based on sequence comparisons of rRNA genes (conserved;
code for RNA components of ribosomes)
Each _____________ represents the divergence of two species. - CORRECT ANSWER -
Branch point
______________ are groups that share an immediate common ancestor. - CORRECT
ANSWER - Sister taxa
A ________________ includes a branch to represent the last common ancestor of all taxa in the
tree. - CORRECT ANSWER - Rooted tree
A _____________ diverges early in the history of a group and originates near the common
ancestor of the group. - CORRECT ANSWER - Basal taxon
A ____________ is a branch from which more than two groups emerge. - CORRECT
ANSWER - Polytomy
What is the difference between phylogeny, systematics, and taxonomy? What kind of evidence is
used to construct phylogenies? - CORRECT ANSWER - Phylogeny is the evolutionary
history of a species or group of species. Systematics is a discipline focused on classifying
organisms and determining their evolutionary relationships. Taxonomy is the naming and
classifying of the diverse forms of life. Phylogenies are constructed using systematics;
specifically, fossils, molecules, and genes.
What is binomial nomenclature? Who is credited with developing this idea? Why is it useful? -
CORRECT ANSWER - Binomial nomenclature is a two-part naming system used to name
organisms. It names things based on their genus and species. Carolus Linnaeus is credited with
developing this. Binomial nomenclature can be useful because common names can be
misleading, and often refer to more than one species.
, What is hierarchical classification? What are the different levels? - CORRECT
ANSWER - Hierarchical classification is a way to identify an organism based on its
taxons.
Domain -> Kingdom -> Phylum -> Class -> Order -> Family -> Genus -> Species
What is a phylogenetic tree? What are branch points? What are common ancestors? - CORRECT
ANSWER - A phylogenetic tree is a branching diagram representing the evolutionary
history of a group of organisms. Branch points are relationships depicted as a two-way
connection. Each branch point represents the divergence of 2 evolutionary lineages from a
common ancestor. Common ancestors are the starting points for phylogenetic trees.
What is a clade? - CORRECT ANSWER - A clade is a group that includes an ancestral
species and all of its descendants?
What are the differences between mono, para, and polyphyletic groupings? - CORRECT
ANSWER - A monophyletic refers to an ancestral species and all of its descendants. A
paraphyletic refers to an ancestral species and some of its descendants. A polyphyletic refers to
many different ancestors.
What are shared derived vs. shared ancestral characteristics? - CORRECT ANSWER -A
shared derived characteristic is an evolutionary novelty unique to a clade; while a shared
ancestral characteristic originated in an ancestor.
What is the three domain system? - CORRECT ANSWER - The three domains are
Bacteria, Archaea, and Eukarya. Every organism fits into a specific domain.
How does horizontal gene transfer differ from vertical gene transfer? - CORRECT
ANSWER - The horizontal gene transfer is a process in which genes are transferred from
one genome to another through mechanisms; specifically, viral infections
ex. colds
Vertical gene transfer is the transmission of DNA from parent to offspring
ex. have baby
Exam Questions and CORRECT Answers
What is the definition of Phylogeny? - CORRECT ANSWER - The evolutionary history of
a species or group of species
What is the definition of Systematics? - CORRECT ANSWER - A discipline focused on
classifying organisms and determining their evolutionary relationships
What is the definition of Taxonomy? - CORRECT ANSWER - A scientific discipline
concerned with naming & classifying the diverse forms of life
What do you know about Binomial Nomenclature? - CORRECT ANSWER - - Invented
by Carolus Linneaus
- It is a 2 part naming system comprised of the Genus (to which the species belongs; first part of
the binomial) and species (specific epithet, species within the genus, second part of binomial)
What do you know about Hierarchical Classification? - CORRECT ANSWER --
Hierarchy of increasingly inclusive categories
- Domain -> Kingdom -> Phylum -> Class -> Order -> Family -> Genus -> Species
- Taxon - the named taxonomic unit at any level of the hierarchy
How is phylogeny reconstructed using morphological characteristics? - CORRECT
ANSWER - Ancestral - a characteristic that originated in an ancestor of the taxon
Derived - an evolutionary novelty unique to a clade
What is the definition of Monophyletic? - CORRECT ANSWER - (Single Tribe) Consists
of an ancestral species and all of its descendants
What is the definition of Paraphyletic? - CORRECT ANSWER - (Beside the tribe)
Consists of an ancestral species & some but not all of its descendants
,What is the definition of Polyphyletic? - CORRECT ANSWER - (Many tribes) Includes
taxa with different ancestors
What is the history of Taxonomy? - CORRECT ANSWER - 1. Two Kingdoms - Animals
and Plants
*Early taxonomists classified all organisms into two kingdoms: plants and anaimals. Even
though they do not do photosynthesis (not photoautotrophic), fungi and bacteria were classified
as plants because they all have cell walls (although Bacteria and Fungi cell walls are quite
different from plant cell walls) Eukaryotic unicellular organisms with chloroplasts (which are
photoautotrophic) were placed in the plant kingdom. Eukaryotic unicellular organismss that
moved and ingested food (heterotrophic ingestive) were classified as animals. Organisms that
moved and were photosynthetic were a problem and claimed by both groups.
2. Five Kingdoms - Robert Whittaker 1969
Prokaryotic: Monera (lack membrane enclosed nucleus and organelles, Bacteria)
Eukaryotic: Protista (single-celled protists -> Algae, catch all), Fungi, Animalia, Plantae
*Despite its problems, the two kingdom system was not replaced until the late 1960's when Dr.
Robert H. Whittaker from Cornell University argued for a 5 kingdom system. Whittaker
recognized two fundamentally different types of cells, prokaryotic and eukaryotic. He named the
prokaryotes (bacteria) Kingdom Monera. He kept the plant kingdom for eukaryotic multicellular
photoautotrophic organisms and the animal kingdom for eukaryotic multicellular heterotrophic
ingestive organisms. He introduced the new Kingdom Fungi for multicellular heterotrophic
absorptive organisms. The remaining eukaryotic organisms, which did not fit into animal, plant,
or fungi kingdoms, were placed in the fifth kingdom, Protista. These organisms were mostly
single celled, but included the multicellular red, green, and brown algae. In general they are
"mixotrophs" which means that some are autotrophic and some heterotrophic.
3. Three Domain System - Eukarya, Archaea, Bacteria
Each c
How were Archaea/Bacteria separated? - CORRECT ANSWER - Archaea does not have
peptidoglycan while Bacteria does
What is the definition of Phylogenetic trees? - CORRECT ANSWER - Branching "trees"
that depict evolutionary relationships
,How is phylogeny reconstructed using molecular methods? - CORRECT ANSWER --
Based on molecular sequence of DNA
- Bacteria/Archaea Classification based on sequence comparisons of rRNA genes (conserved;
code for RNA components of ribosomes)
Each _____________ represents the divergence of two species. - CORRECT ANSWER -
Branch point
______________ are groups that share an immediate common ancestor. - CORRECT
ANSWER - Sister taxa
A ________________ includes a branch to represent the last common ancestor of all taxa in the
tree. - CORRECT ANSWER - Rooted tree
A _____________ diverges early in the history of a group and originates near the common
ancestor of the group. - CORRECT ANSWER - Basal taxon
A ____________ is a branch from which more than two groups emerge. - CORRECT
ANSWER - Polytomy
What is the difference between phylogeny, systematics, and taxonomy? What kind of evidence is
used to construct phylogenies? - CORRECT ANSWER - Phylogeny is the evolutionary
history of a species or group of species. Systematics is a discipline focused on classifying
organisms and determining their evolutionary relationships. Taxonomy is the naming and
classifying of the diverse forms of life. Phylogenies are constructed using systematics;
specifically, fossils, molecules, and genes.
What is binomial nomenclature? Who is credited with developing this idea? Why is it useful? -
CORRECT ANSWER - Binomial nomenclature is a two-part naming system used to name
organisms. It names things based on their genus and species. Carolus Linnaeus is credited with
developing this. Binomial nomenclature can be useful because common names can be
misleading, and often refer to more than one species.
, What is hierarchical classification? What are the different levels? - CORRECT
ANSWER - Hierarchical classification is a way to identify an organism based on its
taxons.
Domain -> Kingdom -> Phylum -> Class -> Order -> Family -> Genus -> Species
What is a phylogenetic tree? What are branch points? What are common ancestors? - CORRECT
ANSWER - A phylogenetic tree is a branching diagram representing the evolutionary
history of a group of organisms. Branch points are relationships depicted as a two-way
connection. Each branch point represents the divergence of 2 evolutionary lineages from a
common ancestor. Common ancestors are the starting points for phylogenetic trees.
What is a clade? - CORRECT ANSWER - A clade is a group that includes an ancestral
species and all of its descendants?
What are the differences between mono, para, and polyphyletic groupings? - CORRECT
ANSWER - A monophyletic refers to an ancestral species and all of its descendants. A
paraphyletic refers to an ancestral species and some of its descendants. A polyphyletic refers to
many different ancestors.
What are shared derived vs. shared ancestral characteristics? - CORRECT ANSWER -A
shared derived characteristic is an evolutionary novelty unique to a clade; while a shared
ancestral characteristic originated in an ancestor.
What is the three domain system? - CORRECT ANSWER - The three domains are
Bacteria, Archaea, and Eukarya. Every organism fits into a specific domain.
How does horizontal gene transfer differ from vertical gene transfer? - CORRECT
ANSWER - The horizontal gene transfer is a process in which genes are transferred from
one genome to another through mechanisms; specifically, viral infections
ex. colds
Vertical gene transfer is the transmission of DNA from parent to offspring
ex. have baby
