Quiz 7
________ is necessary for a population to survive over successive generations in response to environmental changes
Adaptation
The gene pool for a particular gene would include
All the alleles for a particular gene in all the indivduals in a popualtoin
For the Galapose Island Finches species Geospiza fortis, drought conditions produced a change in the population in which the next generation had larger beaks than the previous ones. What produced this change in the population
Birds with larger beaks had higher fitness, so they could produce more offspring that inheritated the same traits
African black bellied seedcracker finches have beaks that are either large or small. Only large beaked birds can crack open hard seeds, and small beaked are more adept at handling small seeds. Both have an advantage over intermediate sized beaks. This is an example of
Disruptive Selection
The only know population of a reptile species lives on an African mountain. the population is relativley large but no close relatives of this species are known. Suppose you could stop all mutations within a popuation and all emigration out of a population. Which statement best describes the probable future of this population
Evolution will continue as natural selection acts on the gentic varibility that exsists in the popualtion
How successful as an indivdal is at passing on its genes to the next generation is known as
Fitness
Shrews have been documented to travel across frozen lakes and establish population on previously uninhabited islands: thus the shrews have a limited gene pool. If this limited gene pool has allele frequencies that are very different from alleles frequencies found in the original population, then this would be an example of
Founder effect
The genetic makeup of any organism is its _____, which determines the physical characterisitcs called its _____
Genotype, phenotype
What is the difference between mircoevolution and macroevolution
Microevoltion describes change within a population over a short period of time, whereas macroevoltion describes larger change such as the formation of new species over longer periods of time
Which of the following statements about evolution is true
Population evlove
How have caesaren sections and intensive neontal (near birth) medical care likey affected the average birth weight of average American babies
Stablizing selection for bith weight no longer has as much of an influence
If every sexually reproducing organism has only two alleles for each gene, how can there be a range of traits for a physical chacteristic
There can be more than two variation of a gene in a population
Which of the human is the "fitest" as far as natural selection is concerned
a person with seven children who was killed in a car accident at age 40
The term "natural selection" is not interchangable with the term "evolution" because
a population may evolve in ways other than through natural selection
A population is
all the members of a species that live in a defined geographic region at the same time
At its most basic level, evolution is
change in the frequency of alleles in a population
You are studying leaf size in a natural population of plants. The secone season is particulay dry, and the following year the average leaf size in the population is smaller than the year before. But the amount of overall variation is the same, and the population size hasn't changed. Also you have done experiments that shows the small leaves are better to adapt to dry conditions than the large leaves. Which of the following has occurred
directional selection
Habitats set aside for endangered species are often sectioned into areas by roads, producing separate small populations. This causes problems in conversation because it reduces
gene flow between popuations
A bottleneck may be dangerous to a population because
genetic variability is diminished
Mutations:
may do nothing, may be harmful, or maybe beneficial
As world travel becomes easier and human popuation intermix, the occurance of what phenomeon will probably decrease
mutation
Which of the following is ultimately responsible for introducing new alleles into a popuation
mutation
Which of the following processes is not an agent of microevlotion
polygenic inheritance
Extreme hunting pressures has caused northern elephant seals to become less genetically diverse because of
population bottleneck
Imagine a popluation of monkeys in South America whose habitiat has been reduced to the point where only 25 monkeys survive. This would be an exaple of
population bottleneck
the mate attracting elaborate plumage of the male peacock is a result od
sexual selection
Evolution by genetic drift is most obvious in
small popualtions
Organisms that can interbreed with each other in nature but are genetically isolated from all others orgamisms are a
species
Disruptive selection operates whenever
the extremes in a distribution of phenotypes are more fit than the average
In order for migration to alter allels frequencies in another popualtion
the gene pool of the migrating popluation must be different from the population it is joining