Exam 4 Bio 101 Jason Jones UNA

Which population is more likely to be affected by genetic drift?

12 squirrels

Lobsters, shrimp, crabs, and their relatives belong to which of the following arthropod groups?

Crustaceans

Approximately how many species of living organisms have currently been formally described?

2 million

Approximately how many species are estimated to currently be present on Earth?

30 million

How many legs do insects have?

6

An allele's abundance within a population is referred to as ____ frequency

Allele frequency

Which animal phylum is the most diverse, in terms of number of described species?

Arthropoda

Which of the following animal phyla is likely the most abundant (in terms of numbers of individuals, not number of species) on Earth?

Arthropoda

Overhunting of species, such as tigers, reduces their numbers and their genetic diversity. This is an example of _____.

Bottleneck

Which of the following locations has the greatest diversity of freshwater mussels?

California

Which of the following cephalopods is the only one with an external shell?

Chambered nautilus

In a tropical forest some leaves are dark green and some are light green. In a population of caterpillars, homozygous dominant dark green caterpillars thrive eating the dark green foliage, while homozygous recessive light green caterpillars thrive eating light green foliage. However, heterozygous caterpillars of an intermediate color green are easily seen by birds and eaten, thus their numbers are far less than the dominants or recessives. This is an example of ____ selection.

Disruptive

In Cameroon, seedcrackers have either small bills (adapted for feeding on soft sedge seeds) or large bills (adapted for feeding on hard sedge seeds). During competition for scarce resources, these birds primarily feed on the seeds for which they are best adapted. This is an example of ____ selection.

Disruptive (birds)

Which of the following groups of mollusks is the most diverse, and is the only group found commonly on land?

Gastropods

Which disease, spread by drinking water containing infected copepods, has almost been eliminated in Africa due to education, water treatment, and provision of filters?

Guinea worm

The Old Order Amish in Lancaster County is descended from one man and woman and has an unusually high frequency of a recessive allele that causes Ellis-van Creveld syndrome. This is an example of ____.

Inbreeding

What is the original source of new alleles?

Mutation

Tapeworms belong to which of the following animal phyla?

Platyhelminthes

____ selection occurs when individuals choose mates with a particular desirable trait.

Sexual

Many male birds will expend a great deal of energy building nests. Females will mate with the males who build the best nests. This is best described as an example of ____.

Sexual selection

Which of the following animals is not an arthropod?

Spider

Fatter sociable weaver birds spend more time foraging where they are vulnerable to predation, are more attractive to predators, and are less likely to escape an attack. Conversely, thin birds risk starvation. Therefore, sociable weaver of an intermediate weight have a selective advantage. This is an example of ____ selection.

Stabilizing

Puppies born too large experience difficulties during birthing and tend to have respiratory and other problems. Puppies born too small often can't compete with their siblings for their mother's milk. Thus, puppies of intermediate size have a survival advantage. This is an example of ____ selection.

Stabilizing

Over evolutionary time, flowering plants have evolved colors, odors, and nectar that attract pollinating insects and the insects have evolved mechanisms that detect the changes in plants and to better collect pollen. This is an example of ____.

coevolution

The fastest lions are able to catch prey, such as zebras; similarly, the fastest zebras are able to escape predatory lions. Over time, the lion and zebra populations become composed of faster and faster individuals. This is an example of ____.

coevolution.

Which of the following is a trait shared by both cnidarians and flatworms?

a digestive system with a single opening

What is the best definition of a population?

a group of interbreeding individuals of the same species in a given area

Hawaiian honeycreepers exhibit diverse beaks that allow them to feed on insects, flowers, and seeds in their different habitats. This is an example of ____.

a key innovation

The emergence of hundreds of Hawaiian honeycreeper species from a single flock introduced to this island archipelago millions of years ago is an example of ____.

adaptive radiation

With the extinction of the dinosaurs 65 million years ago, multiple niches that the dinosaurs once filled opened up and allowed mammals the opportunity to evolve and exploit those niches. This is an example of ____.

adaptive radiation

In the 16th century, a Spanish ship explored a Pacific Island that had a small mountain range separating it. Mice that were on the ship escaped onto the island on both sides of the mountain range. After decades of separation the two populations developed different numbers of chromosomes, resulting in reproductive isolation that prevented any future interbreeding. This speciation event is an example of ____.

allopatric speciation

When a physical barrier separates a population, leading to the evolution of new species on either side of the barrier, ____ has occurred.

allopatric speciation

The branch points on a cladogram represent ____.

ancestor common

In 2000, 87% of the wild rat populations in Stadtlohn, Germany was resistant to the poison bromadiolone. This indicates that ____was/were commonly used as a rat poison(s) here, and the rat's resistance is an example of ____ selection.

bromadiolone; directional

How are new combinations of alleles introduced into chromosomes?

crossing over at Meiosis 1

Alligators more closely resemble lizards than birds; however, alligators and birds have four-chambered hearts, which lizards do not have. In this example, the four-chambered heart is a ____, which indicates that alligators are ____ related to birds than to lizards.

derived character; more closely

One hallmark of speciation is ___

end of gene flow between populations

Phylogeny is most analogous to a ____.

family genealogy

The migratory patterns of many animals encourage ____.

gene flow

The movement of alleles among populations is called _____.

gene flow.

All of the alleles in a population make up the ____.

gene pool

Natural selection drives changes in allele frequencies by influencing traits with a ____ basis.

genetic

A random change in allele frequency over time that is brought about by chance alone is known as ____.

genetic drift

The increased variability in the frequency of the b+ allele in the smaller flour beetle population in the graph above is an example of ____.

genetic drift (b+)

What is one result of the bottleneck effect?

homozygosity

Peahens prefer to mate with peacocks that have the brightest and largest tail displays. The peacock's tail is a disadvantage to the males, because it is large and cumbersome and hinders them from escaping from predators. Given these facts, why isn't the peacock's tail selected against by natural selection?

in spite of the disadvantage, peacocks with larger tails leave more offspring

Environmental pressures result in a(n) ____ of adaptive alleles.

increase in the frequency

A ____ is a structural modification that enables an individual to exploit their habitat more efficiently.

key innovation

Mutations that result in the death of the individual are known as ____.

lethal mutations

A major change in evolutionary patterns over long periods of time is best described as ____.

macroevolution

A female horse can mate with a male donkey but they will produce a mule that is sterile. This is an example of what type of isolation mechanism?

mechanical/ postzygotic Isolating

Any change in allele frequencies in a gene pool is called ____.

microevolution

A cladogram can be viewed as "sets within sets" of derived traits. Which features distinguish the clade containing mice and humans from the other clades in this cladogram?

multicellular with a back, legs, and hair

With ____ selection, the frequency of a favored allele will increase as a phenotypic variation becomes more adaptive.

natural selection

____ increases the frequency of adaptive mutations in a population over time.

natural selection

A ____ mutation changes the DNA sequence but has no impact on the fitness of the individual.

neutral

____ is the study of a species' evolutionary history.

phylogeny

Which animal phylum develops from only two initial germ layers?

phylum Cnidaria

Traits with more than two distinct forms are ____.

polymorphic

In the universal ABO blood grouping system, there are four phenotypes -A, B, AB, and O -which are determined by three different alleles. The presence of three alleles in the ABO blood grouping system is an example of ____.

polymorphism

As part of their body plan, snails and other gastropods exhibit torsion. What is a direct result of this phenomenon?

poop on their head

What type of symmetry is exhibited by cnidarians?

radial symmetry

The process of speciation always includes ____ isolation.

reproductive

The observation that female lions prefer male lions with darker manes is an example of ____.

sexual selection

In Lake Victoria, hundreds of cichlid fish species arose after the lake last dried up 12,400 years ago. This is an example of ____.

sympatric speciation

Two species of toads have been successfully interbred in a laboratory but do not hybridize in nature because one species mates in summer and the other mates in the fall. This is an example of ____ isolation.

temporal

A small Dutch population settled in South Africa in the 17th century and became known as Afrikaners. By chance, a few Dutch settlers carried the gene for Huntington's disease. Today, Huntington's disease occurs at a relatively high frequency in this population. This is an example of ____.

the founder effect