BLG 144 MIDTERM 1 2026 FINAL REVIEW PACK
COMPLETE QUESTION SET AND CORE
CONCEPT SUMMARY
◉ Population. Answer: All the organisms of a particular species
living in the same place at the same time
◉ Gene Pool. Answer: All the alleles of all the genes in a species or
population
◉ Natural Selection. Answer: Differential reproduction based on
heritable traits
◉ Biological fitness. Answer: The ability of an individual to produce
surviving, fertile offspring relative to that ability in other individuals
in the population
◉ Facts of Natural selection. Answer: - requires varied population
-does not create new traits or alleles
-mutations do not occur to solve problems
-adaptations do not occur because organisms want or need them
-evolution is not progressive
,-nat. sel. does not change an organism over its lifetime
-does not make perfect organisms
-A fitness trade-off is a compromise between traits in terms of how
those traits perform in the environment
◉ Fossil Record. Answer: -imprints or remains of organisms that
lived in the past
-reveals the appearance (and disappearance) of organisms in a
historical sequence
◉ Biogeography. Answer: -the study of the geographic distribution
of species that first suggested to Darwin that today's organisms
evolved from ancestral
-species in the same area tend to be more closely related to one
another
-must also consider Continental Drift
◉ Homologous structures. Answer: -comparative anatomy reveals
this
-similarity due to shared ancestry
-different functions, different shape on outside, BUT similar bones
inside
,◉ Vestigial traits. Answer: similar in structure but no longer
functional
◉ Comparative Embryology. Answer: early stages of development
are very similar
-developmental homology
-embryos of vertebrates begin similarly but then develop differently
◉ Molecular biology. Answer: studies look to DNA, RNA, and
proteins for differences and similarities between organisms to
determine how long they may have shared a common ancestor
◉ Anatomy. Answer: the study of an organism's physical structure
◉ Physiology. Answer: the study of how the physical structures in an
organism function
◉ Five causes of Evolution. Answer: 1. Genetic Drift
a. Bottleneck
b. Founder Effect
2. Gene Flow
3. Mutation
4. Natural Selection
, 5. Nonrandom mating (including
sexual selection)
◉ Genetic Drift. Answer: - any change in allele frequencies in a
population due to chance
- random with respect to fitness
>especially prevalent in small
populations
◉ Two cases of Genetic Drift. Answer: - Founder Effect
-Bottleneck Event
◉ Bottleneck Event. Answer: sharp reduction in the size of a
population due to environmental events (such as earthquakes,
floods, fires, disease, or droughts) or human activities (such as
genocide)
◉ Founder Effect. Answer: when a new colony is founded by a small
number of individuals
-Example: Deafness in Martha's
vineyard
>37 to 230 times more
common than rest of US
COMPLETE QUESTION SET AND CORE
CONCEPT SUMMARY
◉ Population. Answer: All the organisms of a particular species
living in the same place at the same time
◉ Gene Pool. Answer: All the alleles of all the genes in a species or
population
◉ Natural Selection. Answer: Differential reproduction based on
heritable traits
◉ Biological fitness. Answer: The ability of an individual to produce
surviving, fertile offspring relative to that ability in other individuals
in the population
◉ Facts of Natural selection. Answer: - requires varied population
-does not create new traits or alleles
-mutations do not occur to solve problems
-adaptations do not occur because organisms want or need them
-evolution is not progressive
,-nat. sel. does not change an organism over its lifetime
-does not make perfect organisms
-A fitness trade-off is a compromise between traits in terms of how
those traits perform in the environment
◉ Fossil Record. Answer: -imprints or remains of organisms that
lived in the past
-reveals the appearance (and disappearance) of organisms in a
historical sequence
◉ Biogeography. Answer: -the study of the geographic distribution
of species that first suggested to Darwin that today's organisms
evolved from ancestral
-species in the same area tend to be more closely related to one
another
-must also consider Continental Drift
◉ Homologous structures. Answer: -comparative anatomy reveals
this
-similarity due to shared ancestry
-different functions, different shape on outside, BUT similar bones
inside
,◉ Vestigial traits. Answer: similar in structure but no longer
functional
◉ Comparative Embryology. Answer: early stages of development
are very similar
-developmental homology
-embryos of vertebrates begin similarly but then develop differently
◉ Molecular biology. Answer: studies look to DNA, RNA, and
proteins for differences and similarities between organisms to
determine how long they may have shared a common ancestor
◉ Anatomy. Answer: the study of an organism's physical structure
◉ Physiology. Answer: the study of how the physical structures in an
organism function
◉ Five causes of Evolution. Answer: 1. Genetic Drift
a. Bottleneck
b. Founder Effect
2. Gene Flow
3. Mutation
4. Natural Selection
, 5. Nonrandom mating (including
sexual selection)
◉ Genetic Drift. Answer: - any change in allele frequencies in a
population due to chance
- random with respect to fitness
>especially prevalent in small
populations
◉ Two cases of Genetic Drift. Answer: - Founder Effect
-Bottleneck Event
◉ Bottleneck Event. Answer: sharp reduction in the size of a
population due to environmental events (such as earthquakes,
floods, fires, disease, or droughts) or human activities (such as
genocide)
◉ Founder Effect. Answer: when a new colony is founded by a small
number of individuals
-Example: Deafness in Martha's
vineyard
>37 to 230 times more
common than rest of US
