EOC Review Category 3: Biological Evolution and
Classification (Answered) 2025/2026. 100%
Verified.
Fossil Record:
This is a series of skulls and front leg fossils of organisms believed to be ancestors of the modern day
horse.
Use the fossil record of the horse Gand give two similarities between the skulls that might lead to
the conclusion that these are all related species.
jaw line, nose bone, location of the eye
Biogeography:
The study of the geographic distribution of organisms. Species that live in the same area are more
closely related to each other and to the fossils in that area. As continents drifted apart species
became separated.
Based on the diagram above, which of the following phylogenetic trees is correct?
Embryology:
studies the similarities between the early stages in development of organisms. Vertebrate animals
have embryos will pharyngeal pouches and tails.
Homologous structures
show individual variations on a common anatomical theme. These are seen in organisms that are
closely related. 5. homologous
, Analogous structures
have very different anatomies but similar functions. These are seen in organisms that are not
necessarily closely related, but live in similar environments and have similar adaptations. 4.
analogous
Vestigial structures
are anatomical remnants that were important in the organism's 3. vestigial
Molecular Biology:
studies the similarities between DNA and proteins in different species.
Cytochrome c is a
protein found in mitochondria. It is used in the study of evolutionary relationships because most
animals have this protein. Cytochrome c is made of 104 amino acids joined together. Below is a list
of the amino acids in part of a cytochrome protein molecule for 5 different animals. Any sequences
exactly the same for all animals have been skipped.
Which organisms are most closely related to each other?
Classification (Answered) 2025/2026. 100%
Verified.
Fossil Record:
This is a series of skulls and front leg fossils of organisms believed to be ancestors of the modern day
horse.
Use the fossil record of the horse Gand give two similarities between the skulls that might lead to
the conclusion that these are all related species.
jaw line, nose bone, location of the eye
Biogeography:
The study of the geographic distribution of organisms. Species that live in the same area are more
closely related to each other and to the fossils in that area. As continents drifted apart species
became separated.
Based on the diagram above, which of the following phylogenetic trees is correct?
Embryology:
studies the similarities between the early stages in development of organisms. Vertebrate animals
have embryos will pharyngeal pouches and tails.
Homologous structures
show individual variations on a common anatomical theme. These are seen in organisms that are
closely related. 5. homologous
, Analogous structures
have very different anatomies but similar functions. These are seen in organisms that are not
necessarily closely related, but live in similar environments and have similar adaptations. 4.
analogous
Vestigial structures
are anatomical remnants that were important in the organism's 3. vestigial
Molecular Biology:
studies the similarities between DNA and proteins in different species.
Cytochrome c is a
protein found in mitochondria. It is used in the study of evolutionary relationships because most
animals have this protein. Cytochrome c is made of 104 amino acids joined together. Below is a list
of the amino acids in part of a cytochrome protein molecule for 5 different animals. Any sequences
exactly the same for all animals have been skipped.
Which organisms are most closely related to each other?
