BYS 120 Quiz Answers

A fruit fly population has a gene with two alleles, A1 and A2. Tests show that 70% of the gametes produced in the population contain the A1 allele. If the population is in Hardy-Weinberg equilibrium, what proportion of the flies carry both A1 and A2?

.42

Consider Figure 26.5 in your textbook. What does each branch point signify?

A node, and/or most recent common ancestor.

Which structure carries blood from the left ventricle to the body?

Aorta

Suppose you are studying two bird species that live in a forest and are not known to interbreed. One species feeds and mates in the treetops and the other on the ground. But in captivity, the birds can interbreed and produce viable, fertile offspring. What type of reproductive barrier most likely keeps these species separate in nature?

Behavioral isolation

According to Aristotle, are plants living or nonliving?

Between living and nonliving.

What was the local doctor's diagnosis of the patients' problems?

Bewitchment

You have excavated a sample you suspect is about 20,000 years old. What radioactive isotope will you use to date the sample?

Carbon-14

What type of ergotism do modern scientists suspect was the culprit in this case?

Convulsive

What structures circulate blood in the blood vessels of the heart?

Coronary arteries

What did early researchers hypothesize as the source of energy for making organic molecules?

Electricity from storms and/or UV radiation

What conditions needed to be kept constant in the experiment?

Exposure time

What did they conclude?

Food is contaminated regardless of exposure time.

Which of the following factors would not contribute to allopatric speciation?

Gene flow between the two populations is extensive.

How did Hutton's and Lyell's ideas influence Darwin's thinking about evolution?

Hutton and Lyell perceived that changes in Earth's surface can result from slow,continuous actions still operating at the present time.

What is the scientific question the Mythbusters were trying to answer?

If the 5-second rule is valid.

If a microbe grew optimally at a low pH, how might this affect its ability to act as a human pathogen?

It would only be effective as a pathogen in areas of the human body that have a low native pH.

How does Lamarckian evolution compare to the Darwinian model?

Lamarck proposed that species evolve resulting from use or disuse of a trait with immediate heritability. Darwinian evolution focuses on the success of a trait.

According to the punctuated equilibrium model

Most new species accumulate their unique features relatively rapidly as they come into existence, then change little for the rest of their duration as a species.

The upper forelimbs of humans and bats have fairly similar skeletal structures, whereas the corresponding bones in whales have very different shapes and proportions. However, genetic data suggest that all three kinds of organisms diverged from a common ancestor at about the same time. which of the following is the most likely explanation for these data?

Natural selection in the aquatic environment resulted in significant changes to whale forelimb anatomy.

What elements did researchers in the 1920s believe the early atmosphere contained?

Nitrogen, ammonia and methane, among others.

Of all the mutations that occur in a population, why do only a small fraction become widespread among the population's members?

Only a small fraction is advantageous to population's members.

Mancuso showed young sunflower plants exhibiting animal behavior. What behavior was that?

Playing

Which of the following is not an observation or inference on which natural selection is based?

Poorly adapted individuals never produce offspring.

Which of the following are assumptions that underlie the use of the molecular clock?

Regions of genomes being compared evolve at a constant rate.

If ergotism was indeed the cause, what was the source of the infection?

Rye

What is the largest organism on the planet?

Sequoia

Which structure carries blood from the upper body to the right atrium?

Superior vena cava

What is their hypothesis?

The 5-second rule is valid.

To what did Darwin compare the plant's radical tip?

The brain of a lower animal.

To what did Mancuso compare the plant's root apparatus?

The internet.

What is half-life?

The time required for half of a radioactive parent isotope to decay to its respective daughter isotope, on average.

Bird guides once listed the myrtle warbler and Audubon's warbler as distinct species. Recently, these birds have been classified as eastern and western forms of a single species, the yellow-rumped warbler. Which of the following pieces of evidence, if true, would be cause for this reclassification?

The two forms interbreed often in nature, and their offspring have good survival and reproduction.

An epitope associates with which part of an antibody?

The variable region

If a mass extinction were caused by a single, catastrophic event (such as asteroid impact), what pattern would you expect regarding the dates when formerly common species lost in the extinction are last observed in the fossil record?

Theoretically, these fossils should be observed right up to the extinction event.

What is the advantage to having memory cells when a pathogen is encountered for a second time?

Two of these answers are correct.

How could they have improved the experimental design?

Used different exposure time intervals.

Did this experiment have a control setup?

Yes

Which of the following represents a homology?

a cat's paw and a human's hand.

What is the major (most obvious) derived trait of humans?

bipedalism

Blood is classified as what type of tissue?

connective

Among the types of heat exchange, which one is the transfer of heat by the movement of air or liquid past a surface?

convection

What unique trait of the chordate will develop into the brain and spinal cord?

dorsal hollow nerve cord

The avian wing and feather were adaptations to facilitate what purpose?

flight

Which animal must eat a larger proportion of its weight in food each day: a house cat or an African lion caged in a zoo?

house cat

DNA sequences in many human genes are very similar to the sequences of corresponding genes in chimpanzees. The most likely explanation for this result is that:

humans and chimpanzees share a relatively recent common ancestor.

Natural selection changes allele frequencies because some ________ survive and reproduce more successfully than others.

individuals

If p is the frequency of allele A, which parts of the Hardy-Weinberg equation correspond to the frequency of individuals that have at least one A allele?

p + half of 2pq

What is a characteristic of early stages of local inflammation?

release of histamine

Which of the following results in long-term immunity?

the administration of the chicken pox vaccine

No two people are genetically identical, except for identical twins. The chief cause of genetic variation among human individuals is:

the reshuffling of alleles in sexual reproduction

What structures of the heart prevents backflow of blood?

valves