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environmental science a - unit 4: exam

Terms in this set (25)

which statement best describes natural selection?
it is the process by which populations of living organisms adapt and change.
which option describes a condition required for natural selection to occur?
production of more offspring than can survive
how does genetic variation help individuals in a population?
it increases the chances of survival and reproduction in a changing environment.
what best defines the fitness of an organism? select all that apply.
ability to survive
ability to reproduce
a region has rabbits with two different coat colors—brown and white. the white rabbits are easily spotted in the grassy field by a hawk from above.

how will natural selection affect the frequency of the trait in the rabbit population?
brown-colored rabbits will increase in number due to lack of predation.
what is biodiversity?
the term describes the variety of life on earth.
what defines a mutation?
any change in the nucleotide sequence of the genome
in north america, apple maggots and hawthorn maggots are commonly observed. the apple-feeding organism developed from the hawthorn-feeding species somewhere between 1800 and 1850 after the introduction of apples in north america. now both organisms are found in the same area but do not feed on the same food items.

which type of speciation is present in these organisms?
sympatric
in inbreeding, closely related individuals reproduce, which reduces the overall genetic variation.

what is the likely significance of low genetic variation in a population?
the population cannot evolve in response to changing environments.
what best defines a genetic disorder? select all that apply.
mutation in a gene
abnormality of a chromosome
what are the causes of biodiversity loss in a given area? select all that apply.
invasive species
change in climate
habitat fragmentation
what is habitat fragmentation?
the process in which a larger habitat gets divided into smaller habitats.
the red-eyed tree frog is found in the canopy of rainforests throughout central america, southern mexico, and south america. it feeds on flies and moths.

what will reduce the population of this frog?
clearing of forest land
what option best defines invasive species?
an organism that is not native to a particular area
kudzu is a plant of the pea family that is native to japan. it was introduced in the united states as a great tool for soil erosion. however, kudzu is now overtaking and displacing other plants of the southeastern united states such as sweetshrub, bee balm, big bluestem, and many more.

which of these is an invasive species?
kudzu
the zebra mussel is a species native to europe that was accidentally introduced to other regions, including the united states.

how has the introduction of this invasive species impacted the ecosystem of the great lakes?
it increases algal blooms
in seneca lake, plankton are the producers that are consumed by many fish. when the fish die, they are decomposed by bacteria. this process releases vital nutrients into the water for producers. zebra mussels are an invasive species that also feed on plankton.

what will be the effect of zebra mussels on the food web if they are introduced into seneca lake?
XXX the number of nutrients in the lake will decrease.
what does it mean to hybridize an organism?
the act of breeding individuals of two different species.
what categorizes a species as endangered?
the species is likely to become extinct either in a specific area or worldwide
when there are less than 2,500 mature individuals of a species, then that species is classified as endangered. the table shows the list of species and their current numbers in the world.

which of these is an endangered species?
cross river gorilla
what is the endangered species act?
it is a program for the conservation of endangered species and their habitats.
what is a gene drive?
it is a genetic engineering technology that guarantees the inheritance of a specific gene in the next generation.
what are the potential uses of a gene drive? select all that apply.
eliminating an invasive species
eliminating the use of pesticides
how does a gene drive work?
it increases the chances of a gene being passed on to the next generation by creating an organism that is homozygous for a desired gene.
how are genes inherited in organisms that are diploid?
a set of genes is passed from each parent organism to the resulting offspring.
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