biology 2 chapter 13

sexual reproduction

2pq

The presence of freckles is due to a dominant allele. Four percent of the individuals in a particular population lack freckles. Use the Hardy-Weinberg formula to calculate the percentage of individuals in this population who are homozygous dominant for freckles.

64%

environmental change, selective pressure, change in population

A drought causes a habitat to turn dry and brown. Green beetles are more visible to birds than brown beetles, so birds eat more green beetles. Brown beetles survive to reproduce more than green beetles do. The brown allele increases in frequency.

If the frequency of one allele in a population is 0.7 in a population with two alleles at a particular locus, what is the frequency of the alternate allele?

.30

In human gamete production there is an average of _____ crossover events per chromosome pair.

2-3

Loxodonta africana and Loxodonta cyclotis

Examine the relationships between the elephants in the figure below. Which one of the following pairs is most closely related?

Which of the following statements about early ideas of evolution is true?

Fossil discoveries in the early 1800s convinced many naturalists that species are not fixed and can change over time.

All the genes in a population are that population's

GENE POOL

The relationship of the genome to an organism is the same as that of the _____ to a population.

GENE POOL

Color is an inherited trait in beetles. If brown beetles move into a population from a nearby island, which of the following statements is correct?

Gene flow causes the frequency of the brown allele to increase.

As proposed by Darwin, what sorts of traits are favored by natural selection?

Heritable traits that help individuals survive and reproduce more successfully than others in the same population.

Which of the following events could NOT be caused by a population bottleneck?

Increased population size

The founder effect differs from a population bottleneck in that the founder effect

Involves the isolation of a small colony of individuals from a larger population

________ believed that use (or lack of use) of body parts enables individual to develop certain traits that it passes on to its offspring while ________ believed that species are fixed forms that do not change over time.

Lamarck Aristotle

The original source of genetic variation that serves as the raw material for natural selection is

MUTATION

The wing of a bat is homologous to the _____ of a whale. blowhole flipper tail rib cage baleen

The bones of a bat wing and a whale flipper are homologous

Which of the following is a characteristic of a population at Hardy-Weinberg equilibrium?

The population is not evolving.

Natural selection can be defined as

a process in which organisms with certain inherited traits are more likely to survive and reproduce than individuals with other traits

Modern travel along with migration reduces the probability of _____ having an effect on the evolution of humans.

genetic drift

Gene flow is accomplished by

Migration

Dr. Doebley and his team compared the DNA sequence of maize to that of a number of teosinte varieties from throughout Mexico. What did their analysis reveal?

maize originated from a variety of teosinte that existed about 9,000 years ago maize is most closely related to a teosinte variety in the Balsas region of Mexico

The study of comparative anatomy

provides information about the evolutionary history of species

According to the Hardy-Weinberg formula, the frequencies of alleles in a population will remain constant if _____ is the only process that affects the gene pool.

sexual reproduction

George Beadle concluded that teosinte is the likely ancestor of maize (corn), even though the two plants appear very different. What evidence did Dr. Beadle collect that led to his conclusion?

teosinte and maize have similar chromosomes, teosinte and maize can produce fertile hybrids

If color is an inherited trait in beetles, and birds are more likely to eat brown beetles than green beetles,

the frequency of the green allele will increase

Which of the following is a population?

the termites infesting your house

A mutation occurs when

there is a change in the DNA sequence of a gene

In which situation can just a few genes dramatically change an organism's entire appearance?

when the genes each control the expression of many other genes

Initially, the patients' HIV populations are genetically identical. By the time they develop full-blown AIDS, how would the viral populations of the fourpatients compare

Each patient's viral population would be unique, specifically adapted to deal with—and overcome—his or her unique immune system responses.

In the example described in the tutorial, the red amoebas survived the catastrophic event, and all future generations of amoebas were red because the red amoebas had a higher reproductive rate than the blue ones.

FALSE

Which one of the following will prevent significant genetic drift?

THE POPULATION SIZE IS LARGE

Which of the following statements about the amoeba population described at the end of the tutorial is true?

It is more vulnerable to extinction due to lack of genetic variation.

Which of the following statements about the voyage of the Beagle is TRUE?

It turned into a tremendous opportunity for Darwin to collect fossils, plants, and animals.

Which of the following is the most recent example of an evolutionary change in populations?

the development of pesticide-resistant insects

Which of the following is an example of natural selection that has been seen in our lifetime?

the evolution of antibiotic-resistant bacteria

Which of the following are homologous?

the forelimb of a dog and the forelimb of a cat

Imagine that a new population of humans is established on a new planet from ten randomly selected people in your biology class. Over thousands of years, the descendants of those ten people reproduce and prosper, but do not reflect well the diversity of humans on Earth. This change in the diversity of people on the new planet is an example of

the founder effect

. A construction company dumps a load of gravel in the bottom of the lake, giving it a mottled appearance. Which outcome would you predict?

The proportion of mottled fish in this population will increase over time.

There is a group of small fish living in a lake with a sandy bottom. Most of the fish are light brown, but about 10% are mottled. These fish are normally prey for large birds that live on the shore. A construction company dumps a load of gravel in the bottom of the lake, giving it a mottled appearance. Which of these statements presents the most accurate prediction?

The proportion of mottled fish will increase over time.

A challenge to traditional (pre-1860) ideas about species came from embryology, where it was discovered that

embryos of dissimilar organisms, such as sharks and humans, resemble each other

Which mechanism for evolution was proposed by Lamarck?

evolution by inheritance of acquired characteristics

In the Hardy-Weinberg formula, what does 2pq represent?

frequency of heterozygotes

Which of the following is NOT a requirement of natural selection?

gene flow

The total collection of alleles in a population at any one time makes up that population's

gene pool

Which of the following are causes of evolutionary change

genetic drift gene flow natural selection mutation

The evolution of populations due to chance is

genetic drift.

In a population with brown and green alleles for color, genetic drift

has more effect on the evolution of a small population.

Homologous pairs of chromosomes are lined up independently of other such pairs during __

metaphase I

Generation-to-generation change in the allele frequencies in a population is

microevolution

Which one of the following can create new alleles?

mutation

A process in which organisms with certain inherited characteristics are more likely to survive and reproduce than individuals with other characteristics is called

natural selection

Chytridiomycosis is a fungal disease first identified in 1998 as a cause of massive amphibian deaths. In some severely impacted populations, a few individuals have survived, perhaps because of some natural resistance. If these resistant individuals continue to survive and prosper, new resistant populations might emerge. This would be an example of

natural selection

The figure below shows what happens in insect populations when crops are sprayed with insecticides. This is an example of

natural selection

Crossing over, resulting in an increase in genetic variation, occurs between

nonsister chromatids of homologous chromosomes

What leads paleontologists to hypothesize that whales evolved from wolf-like carnivores?

observations of fossil teeth

While on the Beagle, Darwin was influenced by a book by Charles Lyell that suggested that Earth was ________ and sculpted by geologic processes that ________ today

old... continue

What do we call scientists who study fossils?

paleontologists

During his trip on the Beagle, Darwin found that

plants and animals living on a continent seemed more closely related to each other than to plants and animals living in similar regions on other continents

natural selection

results in evolutionary adaptation

Which of the following is most likely to decrease genetic variation?

stabilizing selection

Evolutionary biologists studying the evolution of lizard horn length found

that lizard horn length evolved as a defense mechanism against predators

Teosinte kernels are covered in a hard fruitcase, whereas maize kernels are "naked." What happened when Dr. Doebley's team introduced maize's version of the fruitcase gene into teosinte plants?

the teosinte kernels were partially exposed

Natural selection generally results in _

a population that is adapted to its current environment

In the Hardy-Weinberg formula, what does p2 represent?

frequency of the homozygotes for one allele

Organisms from the same phylum all belong to the same

kingdom

The common house mouse species, Mus musculus, has the following taxonomic classification: Mus, Muridae, Rodentia, Mammalia, Chordata, Animalia, Eukarya. Which part of the name is the Family?

muridae

Which of these individuals is a homozygous genotype?

AA

Suppose that every few years, all people over 6 feet tall do not have any children. How will this affect the human population?

Alleles that promote "tallness" will decrease in frequency.

Which of the following is a true statement?

Species with nucleotide sequences that match closely share a common ancestor.

Genetic drift is the result of

CHANCE

Which one of the following statements is TRUE?

Natural selection works on variation already present in a population

Which of the following is an example of sexual selection?

Peahens choose to mate with peacocks that have the most beautiful tails.

According to current evolutionary theory, which of the following is true?

Populations are the units of evolution

While on his voyage on the HMS Beagle, Darwin was strongly influenced by this book.

Principles of Geology by Charles Lyell

Which is NOT a benefit of the understanding of evolution to understanding the field of biology?

Understanding evolution helps us to understand why stars and galaxies change over time.

The digits of a cat are homologous to those of these whale bones.

Which of the following is(are) homologous to the bones in this image?

Natural selection is best described as

a filtering process that fine-tunes the traits of populations by sorting among existing, randomly produced variations

In 1859, Charles Darwin wrote, "The affinities of all the beings of the same class have sometimes been represented by a great tree... As buds give rise by growth to fresh buds, and these if vigorous, branch out and overtop on all sides many a feebler branch, so by generation I believe it has been with the great Tree of Life, which fills with its dead and broken branches the crust of the earth, and covers the surface with its ever branching and beautiful ramifications." At the base of the evolutionary tree of all life is

an organism that is a common ancestor to all living organisms.

HIV has become an important source of mortality for humans. If AIDS persists as a major factor for humans for many generations in the future, natural selection theory predicts that

any heritable traits that help humans survive and reproduce in the presence of AIDS should become more frequent over time

Which of the following is the study of the geographic distribution of species on Earth?

biogeography

Which of the following is a component of the fossil record?

bones of extinct whales

Homology is evidence of _

common ancestry

The similarity of the embryos of fish, frogs, birds, and humans is evidence of _

common ancestry

Genetic drift is a process based on

the role of chance

Scientists working in the fields of both genetics and archaeology have made discoveries that help us understand the origin of maize. Which statement(s) best reflect the way(s) each discipline's work support evidence generated by the other?

Genetics data pinpointed the likely location of the earliest maize domestication, which allowed archaeologists to find fossil evidence of early maize in caves. Geneticists used DNA data to determine how long ago maize was domesticated. Archaeologists then verified the conclusion by dating maize microfossils.

Remember that color is an inherited trait in beetles. Which of the following is an example of natural selection?

Green beetles leave more offspring than brown beetles because they are better at finding food.

The human immune system cannot effectively suppress the HIV virus on its own. What key feature of HIV makes it so hard to beat?

The HIV virus has an extremely high rate of mutation.