BIOB51 2 EXAM QUESTIONS AND ANSWERS WITH COMPLETE
SOLUTIONS VERIFIED
What is a species?
smallest independent evolving unit that follows its own evolutionary path
Why do we have such a difficult time defining species?
because they are no clearly defined lines and hard to compartmentalize for humans
how are extinct species classified(2)
hybridization and morphological differences
how are extant species classified(2)
behaviour, DNA, location
What is the phylogenetic species concept?
smallest group of populations recognizable by unique shared trait
What is the biological species concept?
group of potentially interbreeding populations that are reproductively isolated
What is the general lineage species concept?
metapopulations that evolve indepnedently from other metapopulations
a group of spatially separated populations of one species that interact with each
other
metapopulation
Why do barriers to reproduction often lead to speciation
because after the groups come together, they wont interbreed
, What are geographic barriers?
extrinsic landscape properties that prevent gene flow
What are reproductive barriers
intrinsic properties of organisms that stop them from interbreeding even in sympatry
What is allopatry?
populations that are geographically separated
What is sympatry?
occurs when populations are in the same geographic area
What is allochrony?
species that are reproductively isolated by time
Why are Montastraea corals a good example of allochrony
the timing of gamete release between species is separated by 1.5-3 hrs
How can pollinators serve as premating barriers
different flowers adapt to the preference/behaviour of their pollinators
What is a postmating, prezygotic barrier
barriers associated with the formation of a zygote
What are some examples
physical damage: damage to female rep tract
and gametic incompatibility: failure of sperm/pollen to penetrate or fuse with egg/ovule
What are postzygotic barriers?
reproductive barriers that occur after fertilization and prevent formation of healthy, viable
offspring
four classes of postzygotic barriers
SOLUTIONS VERIFIED
What is a species?
smallest independent evolving unit that follows its own evolutionary path
Why do we have such a difficult time defining species?
because they are no clearly defined lines and hard to compartmentalize for humans
how are extinct species classified(2)
hybridization and morphological differences
how are extant species classified(2)
behaviour, DNA, location
What is the phylogenetic species concept?
smallest group of populations recognizable by unique shared trait
What is the biological species concept?
group of potentially interbreeding populations that are reproductively isolated
What is the general lineage species concept?
metapopulations that evolve indepnedently from other metapopulations
a group of spatially separated populations of one species that interact with each
other
metapopulation
Why do barriers to reproduction often lead to speciation
because after the groups come together, they wont interbreed
, What are geographic barriers?
extrinsic landscape properties that prevent gene flow
What are reproductive barriers
intrinsic properties of organisms that stop them from interbreeding even in sympatry
What is allopatry?
populations that are geographically separated
What is sympatry?
occurs when populations are in the same geographic area
What is allochrony?
species that are reproductively isolated by time
Why are Montastraea corals a good example of allochrony
the timing of gamete release between species is separated by 1.5-3 hrs
How can pollinators serve as premating barriers
different flowers adapt to the preference/behaviour of their pollinators
What is a postmating, prezygotic barrier
barriers associated with the formation of a zygote
What are some examples
physical damage: damage to female rep tract
and gametic incompatibility: failure of sperm/pollen to penetrate or fuse with egg/ovule
What are postzygotic barriers?
reproductive barriers that occur after fertilization and prevent formation of healthy, viable
offspring
four classes of postzygotic barriers
