©PREP4EXAMS@2024 [REAL-EXAM-DUMPS] Monday, July 29, 2024 12:15 PM
BIO-107 test 1 Questions and Answers (100% Pass)
Microevolution - ✔️✔️Evolutionary change below the species level; Change in allele
frequencies over generations. It is called micro evolution because it focuses on
evolution in population, which is the smallest scale. (individuals do not evolve.)
3 mechanisms that cause allele change - ✔️✔️Natural seletion, genetic drift( chance
events that alter allele frequencies), and gene flow (the transfer of alleles between
populations).
Population - ✔️✔️is a group of individuals of the same species that live in the same area
and interbreed, producing fertile offspring.
Gene pool - ✔️✔️We can characterize a population's genetic makeup by describing its
gene pool, which consists of all copies of every type of allele at every locus in all
members of the population.
Fixed - ✔️✔️if only one allele exists for a particular locus in a population.
What does a population geneticist mean when he/she states that the allele for dorsal fin
shape is fixed in a population of great white sharks? - ✔️✔️Means there is no
homozygous/heterozygous makeup for that allele makeup. There is only one allele in
the population to contribute to the shark's dorsal fin shape.
Differential reproduction - ✔️✔️The idea that there is variation in the number of offspring
that individuals within a population produce, is known as Differential Reproduction or
Differential Reproductive Success
Genetic Drift - ✔️✔️Chance events can also cause allele frequencies to fluctuate
unpredictably from one generation to the next, especially in smaller population.
2 kinds of genetic drift. Bottleneck effect and founder effect
1
, ©PREP4EXAMS@2024 [REAL-EXAM-DUMPS] Monday, July 29, 2024 12:15 PM
Explain the role of population size in genetic drift. - ✔️✔️Think of coin flip example 700
heads vs 300 tails is suspicious but 7 heads 3 tails is not. The smaller the number of
coin flips the more likely that chance alone will cause deviation from a predicted result.
Bottleneck effect - ✔️✔️Sudden change in environment, such as a fire or flood, may
drastically reduce population size. This sever drop in pop. Size causes the bottleneck
effect. By chance alone certain alleles may be overrepresented in the survivors and
others may be absent altogether or underrepresented.
Founder effect - ✔️✔️When a few individuals become isolated from a larger population,
this smaller group may establish a new population whose gene pool differs from the
source pop.
For ex. When few members from a pop. Are blown by a storm to an island.
Gene flow - ✔️✔️The transfer of alleles into or out of a population due to the movement of
fertile individuals or their gametes.
Describe how gene flow can act to reduce genetic differences between adjacent
populations. - ✔️✔️Example is the plant fly ex. Suppose there is two wildflower population
near each other and one consists primarily of white flowered, insects carrying pollen
from these plants may pollinate the original population and introduce the CW alleles and
modify the original allele frequencies for the next generation of wildflowers.
b/c alleles are exchanged b/w populations, it tends to reduce genetic differences b/w
populations. Can result in two populations combining into a single one.
Genetic Variation - ✔️✔️differences among individuals in the composition of their genes
or other DNA segments. It is the raw material that natural selection "works on"
Geographic variation - ✔️✔️differences in the genetic composition of separate
populations.
2
BIO-107 test 1 Questions and Answers (100% Pass)
Microevolution - ✔️✔️Evolutionary change below the species level; Change in allele
frequencies over generations. It is called micro evolution because it focuses on
evolution in population, which is the smallest scale. (individuals do not evolve.)
3 mechanisms that cause allele change - ✔️✔️Natural seletion, genetic drift( chance
events that alter allele frequencies), and gene flow (the transfer of alleles between
populations).
Population - ✔️✔️is a group of individuals of the same species that live in the same area
and interbreed, producing fertile offspring.
Gene pool - ✔️✔️We can characterize a population's genetic makeup by describing its
gene pool, which consists of all copies of every type of allele at every locus in all
members of the population.
Fixed - ✔️✔️if only one allele exists for a particular locus in a population.
What does a population geneticist mean when he/she states that the allele for dorsal fin
shape is fixed in a population of great white sharks? - ✔️✔️Means there is no
homozygous/heterozygous makeup for that allele makeup. There is only one allele in
the population to contribute to the shark's dorsal fin shape.
Differential reproduction - ✔️✔️The idea that there is variation in the number of offspring
that individuals within a population produce, is known as Differential Reproduction or
Differential Reproductive Success
Genetic Drift - ✔️✔️Chance events can also cause allele frequencies to fluctuate
unpredictably from one generation to the next, especially in smaller population.
2 kinds of genetic drift. Bottleneck effect and founder effect
1
, ©PREP4EXAMS@2024 [REAL-EXAM-DUMPS] Monday, July 29, 2024 12:15 PM
Explain the role of population size in genetic drift. - ✔️✔️Think of coin flip example 700
heads vs 300 tails is suspicious but 7 heads 3 tails is not. The smaller the number of
coin flips the more likely that chance alone will cause deviation from a predicted result.
Bottleneck effect - ✔️✔️Sudden change in environment, such as a fire or flood, may
drastically reduce population size. This sever drop in pop. Size causes the bottleneck
effect. By chance alone certain alleles may be overrepresented in the survivors and
others may be absent altogether or underrepresented.
Founder effect - ✔️✔️When a few individuals become isolated from a larger population,
this smaller group may establish a new population whose gene pool differs from the
source pop.
For ex. When few members from a pop. Are blown by a storm to an island.
Gene flow - ✔️✔️The transfer of alleles into or out of a population due to the movement of
fertile individuals or their gametes.
Describe how gene flow can act to reduce genetic differences between adjacent
populations. - ✔️✔️Example is the plant fly ex. Suppose there is two wildflower population
near each other and one consists primarily of white flowered, insects carrying pollen
from these plants may pollinate the original population and introduce the CW alleles and
modify the original allele frequencies for the next generation of wildflowers.
b/c alleles are exchanged b/w populations, it tends to reduce genetic differences b/w
populations. Can result in two populations combining into a single one.
Genetic Variation - ✔️✔️differences among individuals in the composition of their genes
or other DNA segments. It is the raw material that natural selection "works on"
Geographic variation - ✔️✔️differences in the genetic composition of separate
populations.
2
