2nd Evolution Quiz Flashcards
population
organisms of the same species but in a different geographical region
-numbers of organisms in a particular place at a particular time
species
all of the same kinds of organisms capable of reproducing
- morphological species concept
- biological species concept
- scientists compare physical traits to identify species
- organisms of different species don’t interchange genetic info
features of a population
- morphological trait: physical descriptions
- physiological traits: how cells and body parts work during growth and reproduction
- behavioral traits: how organisms respond to basic stimuli
morphs
distinct forms of traits
-polymorphism: lots of variation
gene pool
- all of the genes in a population
- a pool of genetic resources shared by all members of a population and their descendants
- large population = large gene pool = usually good
which allele ends up in which gamete depends on…
1) gene mutations
2) crossing over in meiosis 1
3) independent assortment
4) fertilization
- combined alleles from 2 parents
5) chromosomal mutations
- i.e. down syndrome
- all of this leads to genetic diversity
genetic diversity
genetic differences among members of a population
- high genetic diversity = many different alleles for each characteristic
- to have large genetic diversity, you need a large gene pool
allele frequencies
the abundance of each kind of allele in a population
- you can track the rate of genetic change by observing allele frequencies in each generation
- allele frequencies range from 0 to 1
Genetic Distinct Populations 1: Adaptation to Local Environmental Conditions
individual organisms within a population are not genetically identical, so some individuals have genetic combinations that are valuable for survival in the local environment
Genetic Distinct Populations 2: Founder Effect
when some organisms leave a population and start their own colony, all of the fit ire generations of that colony will have the same genetic makeup as the colony’s founders, not the population the founders came from
Genetic Distinct Populations 3: Genetic Bottleneck
caused by a natural disaster that wipes out a lot of the population, even the stronger organisms
-the generations afterwards will have genetic makeup like the survivors, not those before them that died
Genetic Distinct Populations 4: Barriers to Movement
when populations are divided by natural barriers (mountains, etc), they’ll grow and colonize separately and have different allele frequencies
Genetic Diversity Factor 1: Mutations
they introduce new genetic information into a population by changing alleles that are already present
-the helpful ones get passed down
Genetic Diversity Factor 2: Sexual Reproduction
sex makes new combinations of alleles, so the future generations get more and more superior
Genetic Diversity Factor 3: Migration
-when organisms leave, genetic information is subtracted
-when they come, genetic information is added
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Genetic Diversity Factor 4: Population Size
small population = less genetic diversity
big population = more genetic diversity
genetic flow and genetic drift
-genetic flow: moving people from 1 population to another, eventually causing genetic drift
genetic drift: the changing of allele frequencies
evolution
the change in frequency of genetically determined characteristics within a population over time
microevolution and macroevolution
microevolution: small scale
macroevolution: large scale
