Phenotypic and Genetic Variation Flashcards
define an individual.
a physiological integrated unit that developed as a zygote made by sexual reproduction
why would the definition of individual in bacteria, archaea, plants, and some protists have to be flexible?
a zygote can be asexual or can do cloning
what is a population?
a group of individuals of a given species living in the same place at the same time, and usually reproducing with one another (asexual reproduction kind of alters this a little bit). genetically and demographically cohesive.
why are boundaries between populations not as set in strong?
due to genetic exchange between individuals from different populations, by immigration or long distance gamete transport
what is a gene pool?
the entire collection of alleles in a population at a given time
what is a species?
a collection of populations containing individuals that could potentially interbreed successfully
what is a component of phenotypic variation that correlates with the environment?
variation in the environment that an individual experiences while developing could have an impact on phenotypic variation, but does not necessarily entail evolutionary change
q
where does a good portion of genotypic variation arise from?
the reshuffling of existing alleles that occur during sexual reproduction
what does a diploid genotype have?
one set of chromosomes from mother, one set from father, and the gametes that it makes recombination of maternal and parternal alleles through crossing over of homolgous chromosomes, and the independent assortment of alleles on diff. chromosomes
how can bran new alleles enter a population?
- means brand new DNA sequences
- genetic exchange with a different population
- referred to as gene flow
Explain gene flow. What does it include?
- could involve the long distance transfer of gametes between individuals in different populations
- could occur through the immigration of a reproductively mature individual into a population, that later reproduces with someone in the population
what is the main source of new DNA sequences in a species?
- mutation
- can involve lots of diff. mechanisms
- Ex. point mutations (single base pair), structural changes in chromosomes, duplication, new whole genomes
what is genetic polymorphism?
the inheritance of a trait controlled by a single genetic locus with two alleles
what is genetic polymorphism important in?
phenotypic variation
most trait variation is ____ rather than discrete
continuous
