Correct Answers 2026-2027
Evolution - CORRECT ANSWER -
Descent with modifications; the idea that living species are descendants of ancestral specie
s that were different from the present day ones.
Natural Selection - CORRECT ANSWER -
A process in which individuals that have certain inherited traits tend to survive and reprod
uce at higher rates than other individuals because of those traits.
Evolutionary Adaptation - CORRECT ANSWER -
A genotype of inherited traits that enhance an individuals ability to survive and reproduce i
n a particular movement.
Homology - CORRECT ANSWER -Similarity in characteristics resulting from a shared ancestry.
Vestigial Structures - CORRECT ANSWER -
A feature of an organism that is a historical remnant of a structure that served a function i
n the organism's ancestors. Ex. pelvis and leg bones in some snakes
Convergent Evolution (Analogous Structure) - CORRECT ANSWER -
The evolution of similar features in independent evolutionary lineages. In such examples in
which species share features because of convergent evolution, the resemblance is said to b
e analogous, not homologous. Analogous features share similar function but not common a
ncestry.
Biogeography - CORRECT ANSWER -
The scientific study of the past and present geographic distributions of species.
,Endemic - CORRECT ANSWER -
Referring to a species that is confined to a specific geographic area.
Microevolution - CORRECT ANSWER -
Evolutionary change below the species level; change in the allele frequencies in a populatio
n over generations.
Modern Synthesis - CORRECT ANSWER -
A consolidation of the results of various lines of investigation from the 1920s through the 1
950s that supported and reconciled the Darwinian theory of evolution and the Mendelian l
aws of inheritance in terms of natural selection acting on genetic variation
Genetic Drift - CORRECT ANSWER -
A process in which chance events cause unpredictable fluctuations in allele frequencies fro
m one generation to the next. Effects of genetic drift are more pronounced in small popula
tions.
Gene Flow - CORRECT ANSWER -
The transfer of alleles from one population to another, resulting from the movement of fert
ile individuals or their gametes.
Mutation (Point mutation and chromosomal changes) - CORRECT ANSWER -
A change in the nucleotide sequence of an organism's DNA or in the DNA or RNA of a viru
s.
P.M. - A change in a single nucleotide pair (base pair) of a gene. Ex. Sickle cell anemia
C.C. - Deletion, insertion or rearrangement of already present loci. Frequently harmful.
Population - CORRECT ANSWER -
A group of individuals of the same species that live in the same area and interbreed, prod
ucing fertile offspring.
, Gene Pool - CORRECT ANSWER -
The aggregate of all copies of every type of allele at all loci in every individual in a populat
ion. The term is also used in a more restricted sense as the aggregate of alleles for just on
e or a few loci in a population.
H.W.E. & Association Assumptions - CORRECT ANSWER -
The state of a population in which frequencies of alleles and genotypes remain constant fr
om generation to generation, provided that only Mendelian segregation and recombination
of alleles are at work.
Founder Effect - CORRECT ANSWER -
A few individuals become isolated from larger population and establish a new population w
hose gene pool differs from the source population. Ex. the remarkably high deaf population
of Martha's Vineyard, which resulted in the development of Martha's Vineyard Sign Langu
age
Bottleneck Effect - CORRECT ANSWER -
Size of population is reduced by a sudden change in environment and the surviving gene p
ool differs from original population. Ex. Illinois Greater Prairie Chicken
Modes of Selection - Directional
Disruptive
Stabilizing - CORRECT ANSWER -Directional -
Common in environments that undergo fluctuations or where migration is common. Ex. Eu
ropean black bears - increase in size during glacial periods
Disruptive - Extreme traits favored. Ex. Cameroon black-bellied seed-cracker finches.
Stabilizing -
Moderate is favored. Ex. Gall forming insects. *If gall is too large, obvious to predators (bir
ds) if gall is too small, inhabitant is vulnerable to parasites.