7a slides Flashcards
what is the endosymbiont theory
-prokaryote engulfed other prokaryotes
-gave rise to animal/fungi lineage and plant/algae lineage
why do prokaryotes and eukaryotes regulate gene expression
in response to cellular and environmental cues
in multicellular eukaryotes what does gene expression regulate
development and is responsible for differentiation of cell types
what is phenotype product of
inherited genotype and many environmental infleunces
genetic variation
differences in composition of genes between individuals
phenotype
observable physical and physiological traits of an orgabism which are determined by its genetic makeup
genotype
genetic makeup or set of alleles of an organism
what makes evolution possible
genetic variation
why is genetic vriation within a population a prerequisite for evolution
within a population genetic idfferences among indiduals provde the raw material on which natural selection and other mechanismsi can act. Without such differences, traits could not change oer time- and hence the population could not evolve
what are two ways new genes and alleles can arise
mutation or gene diplication
how cna sexual reproduction add to the genetic variation among individuals
by recombiing existing alleles
which mutations are passed to offspring
mutations occurring in gametes
what can extend genome length
duplication of genes de to errors in meiosis
true or false
duplicated genes can take on new functions by further mutation
true
in organisms that reproduce sexually how does most genetic variation result
recombination of alleles