Deck 4: The Processes of Evolution

Question 1

Sickle cell anemia is found

A)only in blacks.
B)only in tropical regions.
C)only in people who have had malaria.
D)in whoever inherits the mutant genes.

Answer 1

in whoever inherits the mutant genes.

Question 2

The form of genetic drift that involves alleles passed on to new generations in frequencies unlike those of the parents' generation is called

A)gamete sampling.
B)gene flow.
C)the founder effect.
D)fission.

Answer 2

gamete sampling.

Question 3

Mutations

A)occur at random.
B)happen when they are needed for better adaptation.
C)would not occur if there were no radiation,pollution,and the like.
D)are always deleterious.

Answer 3

occur at random.

Question 4

Clustered groups within a species are called

A)races.
B)subspecies.
C)varieties.
D)breeding populations.

Question 5

We sometimes have difficulty determining the identity of species because

A)species are continually evolving and changing relative to one another.
B)we don't know enough about genetic differences to make this determination.
C)species are not real natural units anyway.
D)species are just human constructions,classified for our convenience.

Question 6

Fission produces new populations that

A)are genetically identical.
B)eventually will become separate species.
C)are less well adapted that the original population.
D)have different genetic make-ups.

Question 7

When a population splits into two or more new populations,the process is

A)fission.
B)gene flow.
C)founder effect.
D)gamete sampling.

Question 8

The adaptive fitness of a mutation is based on

A)the number of loci involved.
B)the extent of its phenotypic effects.
C)how often it occurs.
D)the environment in which the species lives.

Question 9

Mutations are

A)always harmful.
B)always more beneficial than previous forms of the gene.
C)the source of new genetic variation.
D)produced only when there is too much radiation or chemical pollutants.

Question 10

Evolution takes place within

A)individuals.
B)cells.
C)the DNA of the cell nuclei.
D)populations.

Question 11

Genetic drift is more effective in

A)large populations.
B)populations of single-celled organisms.
C)human groups.
D)small populations.

Question 12

In the example of Darwin's finches,there were changes in beak size because

A)some finches changed their beak size in response to environmental changes.
B)environmental variables directly affected how large beaks would grow.
C)finches with larger beaks had an advantage in obtaining food during an environmental crisis.
D)a mutation occurred that gave the finches a needed change in beak size.

Question 13

The abnormal allele for sickle cell is

A)dominant.
B)recessive.
C)codominant.
D)neutral.

Question 14

Members of the same species

A)all look the same.
B)all have exactly the same adaptations.
C)can interbreed and produce fertile offspring.
D)all have identical alleles.

Question 15

When new sets of allele frequencies result from population fissioning,the result is called

A)gene flow.
B)the founder effect.
C)genetic drift.
D)the production of new species.

Question 16

The mutation that leads to sickle cell anemia is an example of

A)a chromosomal mutation.
B)a point mutation.
C)a mutation of many genetic loci.
D)a neutral mutation.

Question 17

In terms of evolutionary success,sickle cell anemia may be considered

A)always beneficial.
B)virtually 100% fatal.
C)deleterious only to those exposed to malaria.
D)a problem only to blacks.

Question 18

Gene flow occurs when

A)a population splits in two or more parts.
B)allele frequencies change over long spans of time.
C)genes are shared among two or more populations.
D)reproduction passes on nonrepresentative samples of parents' genes.

Question 19

The true measure of adaptive success in natural selection is

A)whether an individual lives or dies.
B)how many offspring are produced.
C)how well adapted the individual is.
D)how well adapted the species is.

Question 20

When the gene pools of two populations mix,producing a gene pool with new allele frequencies,the process is called

A)genetic drift.
B)gene flow.
C)fission.
D)the founder effect.

Question 21

Even though sickle cell confers no advantage in the malaria-free U.S.,African Americans have a relative high incidence of the gene.This is an example of

A)the results of poor nutrition and medical care.
B)how the different races are differently adapted.
C)the founder effect.
D)gene flow.

Question 22

The frequency of the sickle cell allele is related to culture in that

A)quality of medical care differs in different parts of the world.
B)irrigation farming provides breeding grounds for mosquitoes.
C)different levels of cultural complexity can affect the genes one has.
D)the disease affects the level of cultural sophistication a society may achieve.

Question 23

The sickle cell gene,a genetic lethal,is found in high frequency in some areas because

A)the mutation has occurred only among those people.
B)the people in those areas are immune to sickle cell anemia.
C)the gene can confer a resistance to malaria.
D)modern medicine has perfected a cure.