Bio 41 Exam #2

How was the distribution of humans (after they evolved) affected by continental drift?

D. The supercontinent of Pangaea split apart and the resulting continents were in their present-day locations by the time modern humans evolved. This would have slowed the distribution of humans until they developed ways of easily traveling the oceans.

In a fictional movie set in a land dominated by flowering plants, advancing and retreating glaciers, and a cast that includes a human, a wooly mammoth, a saber-toothed cat, and dinosaurs, the ________ would be most out of place in the setting according to the geological time line of life on Earth.

D. dinosaurs

In comparison to past estimates, extinction rates are currently high. Which of the following is the MOST plausible explanation?

D.Humans are affecting many aspects of the global environment.

The mass extinction at the end of the Ordovician period killed

a.50 percent of marine animal families, including many trilobites.

What would happen to nutrient cycling in a forest ecosystem if all of the bacteria, protozoans, fungi, and worms were eliminated?

a.Dead plant and animal matter would accumulate more quickly than it is decomposed, and the soil would become depleted of nutrients.

Why would a food web rather than a food chain be the preferred way to represent the movement of food through the community?

a.Food chains are oversimplified and suggest that a consumer eats only a single food item.

The correct two-word Latin scientific name for modern humans is

a.Homo sapiens.

Once a climax community develops, is it likely to remain that way indefinitely?

a.No; over long-term timescales climate change will probably occur, causing the community to eventually change.

Atmospheric scientists anticipate a 3.5°C temperature rise in the next century. What impacts would such a change bring?

a.Some plant and animal species would migrate to cooler locations, whereas others would become extinct.

The mass extinction at the end of the Cretaceous period about 65 mya is believed to have been caused by a massive comet or asteroid smashing into what is now known as the Yucatan Peninsula in the Gulf of Mexico. The debris arising from this impact would have blocked the sun's rays from reaching Earth. How would this cause a mass extinction?

a.With no sunlight, the plants would not be able to photosynthesize and they would die. Any animals that fed on those plants would also die and this chain reaction would continue up the food chain.

In which of the following environments would archaea be expected but not bacteria?

a.a hydrothermal vent

Which of the following communities would be considered to have the greatest species richness?

a.an elk gut with 240 species of microorganisms, where 95 percent of the microorganisms are bacteria

Many of the 7,000 crops cultivated or collected by humans for food contain seeds encased in a fruit like the one seen in the image below. These types of crops are ________ in kingdom ________.

a.angiosperms; Plantae

Archaeans are often referred to as "extremophiles" because they are

a.capable of living in extreme environments where other organisms cannot function.

Which of the following organisms are extant eutherian mammals and most closely related to humans?

a.chimpanzees

Between late 1997 and mid-2008, satellites observed that warmer-than-average ocean temperatures led to below-average chlorophyll concentrations in the oceans. This finding suggests that continued warming of Earth's oceans could lead to a(n) ________ in net primary productivity in the oceans, and the oceans would, therefore, remove ________ carbon dioxide from the atmosphere.

a.decrease; less

Ecologists often define an ecosystem by describing how ________ and ________ are acquired and distributed by the biotic community.

a.energy; nutrients

A single-celled organism has linear DNA enclosed within a nucleus. This organism must be a(n)

a.eukaryote because it has a nucleus.

Burning forests will ________ carbon levels in the atmosphere, which will ________ climate change.

a.increase; increase

In a neighborhood with an area of 500 acres, there are 3,000 mosquitoes. The population density in this neighborhood

a.is 6 mosquitoes per acre.

Branches on the evolutionary tree are sometimes rearranged by scientists because

a.new, related fossils or new information about existing fossils changes the understanding of the relationships.

Prokaryotes that are observed attaching onto nonliving surfaces most likely possess

a.pili.

The bacterium that causes strep throat would be a ________ that belongs to ________.

a.prokaryote; domain Bacteria

The figure below shows the number of living taxonomic families that existed on Earth during the last 540 million years. The sudden decreases in family numbers at 445, 360, 250, 200, and 65 million years ago represent Earth's five mass extinction events. Based on this data, which mass extinction had the biggest impact on the overall diversity of life on Earth?

b.250 million years ago

Which of the following situations illustrates a link between the effects of density-dependent and density-independent factors?

b.A drought occurs; a small herd of deer survives, whereas a larger herd in the same area perishes.

Study the food web shown below. What would be a reasonable outcome following the complete disappearance of wolves?

b.Coyotes may increase because one of their primary predators is gone.

It is possible that modern humans may have comingled with which of these other ancestors?

b.Homoneanderthalensis

The figure shown below illustrates how, although pines first established themselves as the dominant tree in the Lake Michigan sand dune community, black oaks ultimately become the dominant species. What bestexplains the gradual reduction of the pine?

b.Pine needles and the shade from existing pines improve the soil composition and moisture, allowing oaks to become established and preventing new pines from surviving.

The sea star Pisaster ochraceus is a keystone species. Ten years after P. ochraceus is removed from selected intertidal communities along the Washington coast, how might those communities compare to control communities?

b.Sea star prey, such as mussels, might increase in abundance and crowd out other community members.

Which of the following statements about communities is true?

b.There can be complex interactions between the organisms that make up a community.

Not all gases are greenhouse gases. A greenhouse gas is a gas that

b.absorbs heat that radiates away from Earth's surface.

In the late spring, Miles moves into a new house with a small tree growing in the yard. The flowers on this tree have five white petals tinged with pink. Later in the summer, he notices a small fruit where each of the flowers had bloomed. Miles does not take long to realize this is an apple tree, Malus pumila. This apple tree is a(n) ________ from kingdom Plantae.

b.angiosperm

Photosynthetic ________ would NOT have chloroplasts.

b.bacteria

Like the first plants that evolved to live on land, the ________ (liverworts and mosses) living today thrive as very simple plants with extremely flat, thin bodies that can directly absorb water into their cells.

b.bryophytes

Human activities

b.can alter nutrient cycles on local and global scales.

A predictable pattern in which the population sizes of two species increase and decrease in response to each other's densities is called a(n)

b.cyclical fluctuation.

There were 5.2 people per acre in 2012. A census in 2017 found there were 1.2 people per acre. This change represents a(n) ________ in population ________.

b.decrease; density

Bacterial conjugation is the process in which a bacterium

b.exchanges DNA directly with another bacterium.

A J-shaped population growth pattern indicates that a population is

b.growing at its maximum rate and birth rates are higher than death rates.

Species that will most likely prosper as projected climate change occurs will

b.have broad tolerances and can live in a variety of habitats.

Monotremes, like the duck-billed platypus, are egg-laying mammals covered in hair, have mammary and skin glands, have three ear ossicles, are diphyodont, and possess dentary-squamosal jaw articulation. Marsupials, such as kangaroos and koalas, are pouched mammals that have a vertical tympanic membrane in addition to possessing characteristics observed in monotremes.

b.having a vertical tympanic membrane

Consider that fossils of Homoerectus dating between 1.66 and 1.85 mya have been found scattered across Eastern Europe through China and Southeast Asia and dating back to 2.4 mya in Africa.

b.hominins migrated north from Africa, spreading out across Europe and Asia at least twice.

Carbon dioxide levels are increasing because

b.humans have begun releasing carbon that was formerly sequestered in fossil fuels into the atmosphere.

A species of bat is removed from a community after it is hunted to extinction. Within two years scientists notice seeds from several plants are no longer germinating. The bat was a

b.keystone species.

Your spacecraft crash-lands on an airless, lifeless moon. All that survives, along with the crew and you, are some chickens, cornflakes, and vitamins. The air and water recyclers are functioning. To maximize the food supply until a rescue craft arrives, you and the crew should

b.kill all the chickens immediately, eat them first, and then eat the cornflakes.

Heterotrophic bacteria and archaeans that are decomposers are important in

b.nutrient cycling.

Into which category would a human be assigned when eating pepperoni pizza?

b.primary and secondary consumer

Over one particular week in August, the average air temperature is 36°C in the Midwestern United States. This is a reference to

b.weather.

Grapes harvested and crushed into juice will often produce a fermented beverage containing alcohol. Grains (such as wheat, barley, rye, or corn) will also produce an alcoholic beverage if they are soaked and allowed to ferment. Which of the following organisms, naturally present in the environment, is the likely cause of the fermentation?

b.yeasts

The following numbered sets each represent a distinct group of organisms:(1) three toes per foot, cold-blooded, feathers, no finger adaptations(2) three toes per foot, warm-blooded, body hair, opposable thumbs(3) three toes per foot, warm-blooded, feathers, no finger adaptation(4) three toes per foot, warm-blooded, body hair, no finger adaptations

c.1, 3, 4, 2

An archaeological dig in Africa discovers a collection of stone tools along with several skeletons in a cave.

c.Australopithecusafarensis

Scientists use existing fossils to predict what the transitional forms between organisms might look like. Why might it be so hard for scientists to find fossils of these transitional forms?

c.Fossils of transitional species may have never formed due to environmental conditions, or if they did form, natural processes like erosion may have destroyed them.

A giant puffball mushroom can produce and release trillions of spores. With this many spores produced, why do giant puffball mushrooms undergo logistic growth in established habitats?

c.Limiting resources, such as food, water, and space, control the maximum population size of all species.

When researchers found a fossilized jawbone from a late (about 43,000-45,000 years ago) Italian Neanderthal, they noted that the shape of the jawbone suggested the individual had an intermediate chin instead of no chin like most Neanderthals.

c.Modern Homosapiens and Homoneanderthalensis successfully bred with each other while both were present on the Italian peninsula of Europe.

Is it reasonable to expect that all habitats suitable for a given organism will have the same carrying capacity for that organism?

c.No; an organism may be able to live in many locations, but the resources it requires may be available in varying amounts.

Rafael is relaxing on the veranda of his beachfront home on the Gulf of Mexico when he notices a small (about 5 inches long) green quadruped clinging to the ceiling.

c.Reptilia

The levels of carbon dioxide in the atmosphere

c.are estimated to be higher than at any time in the past 420,000 years.

As a group, prokaryotes

c.are single-celled and lack a nucleus.

Cutting down trees in a forest can affect the flow of a river. This is an example of a(n) ________ factor affecting a(n) ________ factor.

c.biotic; abiotic

Ribosomes can be found in ________ cells.

c.both prokaryotic and eukaryotic

In the absence of ________, nutrient recycling within the ecosystem would completely stop.

c.decomposers

The size of a population can be decreased by

c.emigration.

The top of the "S" in an S-shaped curve indicates that the population

c.has reached its carrying capacity.

Escherichia coli, a bacterium that normally lives in the gut of humans, will have the shortest generation time when it is found

c.in an incubator set close to human body temperature.

Yeasts provide leavening in bread by metabolizing the starches and sugars present in flour. Carbon dioxide bubbles are produced when the ________ present in yeast cells use(s) the sugars for cellular respiration to produce energy for the cell.

c.mitochondria

Evidence indicates that archaic Homosapiens gave rise to which of the following?

c.modern humans and Homoneanderthalensis

Citizen science projects contribute to scientific research by the public

c.participating in the collection of data.

Gymnosperms and angiosperms are believed to be more closely related to one another than the other major plant groups because

c.they provide their embryos with stored food in seeds.

Which of the following has the highest population density?

d.1,500 oysters living in an area of 1,500 square meters

A population is counted at 100 individuals in 1998. In 2006, a new count found 1,600 individuals. The doubling time for the population is ________ year(s).

d.2

Which of the following populations would be MOST vulnerable to an outbreak of disease?

d.250,000 people living in an area of 100,000 square meters

Which of the following is NOT an easily testable hypothesis regarding net primary productivity?

d.An increase of water in a marine ecosystem will likely result in tastier products of NPP.

Why is the existence of food webs important even though food chains also exist?

d.Food webs tie together many more organisms than a food chain does. If one organism in a food chain disappears, a food web may allow the organisms in the chain to survive based on their interactions with other organisms.

Which of the following is the strongest evidence that suggests Homosapiens may have intermingled with other species such as H. heidelbergensis and H. neanderthalensis?

d.Fossils from all or some of these Homo species dating to the same time period and found in overlapping geographic areas, showing phenotypes intermediate to at least two of the other species as well as evidence of DNA shared between the species, would suggest that they may have intermingled with each other.

What best describes the relationship between cutting down forests and changes in atmospheric carbon dioxide levels?

d.In the absence of forest plants, there would be less carbon dioxide removed from the atmosphere for use during photosynthesis.

Biodiesel fuel is produced from oils synthesized by and harvested from living plants. How does the use of biodiesel fuel compare to the use of fossil fuels with respect to the amount of carbon dioxide released into the atmosphere?

d.It is beneficial; because living plants are the source of the biodiesel, burning it simply represents nutrient recycling.

Resolving the relationship between the various kingdoms has been challenging because species often resemble one another. For example, the kingdom ________ contains some organisms that are animal-like and others that are plant-like.

d.Protista

Which of the following is an advantage of bipedalism in hominins?

d.The hands are free to carry food, tools, and weapons.

Is it possible for Homo sapiens and Neanderthals to be related even if humans are not the direct descendants of Neanderthals?

d.Yes, because humans and Neanderthals share a common ancestor.

Evolutionary tree diagrams representing the relationships between various organisms can be drawn only when those organisms share a

d.common ancestor.

The success of ending the spread of Zika virus through the use of genetically modified (GM) mosquitoes is NOT dependent on

d.development of a Zika vaccine.

Predators CANNOT

d.drive their prey to extinction.

Cells that lack membrane-enclosed organelles and have a single loop of DNA may be

d.either bacteria or archaea.

Increased carbon dioxide levels in the atmosphere have contributed to acidification of the oceans.This change of the water's pH due to a change in CO2 concentrations is an example of how ________ has/have affected a(n) ________ factor in the biosphere.

d.human activities; abiotic

Historically, an unusual aspect of the recent rise in CO2 levels is that

d.it has occurred relatively rapidly.

Microbes that make up the domains Bacteria and Archaea are most similar in their

d.lack of membrane-enclosed organelles.

Protists and other organisms that use energy and carbon from a variety of sources to fuel their growth and reproduction are most appropriately referred to as

d.mixotrophs.

Which of the following groups of organisms would NOT be considered consumers?

d.photosynthesizers

Based upon the evolutionary traits visible in blooming rose bushes in a garden, a reasonable deduction would be that the

d.presence of flowers means they are angiosperms.

Energy does not cycle through an ecosystem. This is because energy enters an ecosystem through photosynthesis as it changes to chemical energy. This is then used to fuel metabolic activities in

d.producers, consumers, and decomposers, and all of the excess energy is lost as metabolic heat.

It is particularly important for pregnant women to carefully wash their hands and take other precautions if they have a pet cat and are changing the litter box. An organism occasionally carried by cats, pig, and sheep can infect humans and pass from mother to child in utero, resulting in severe symptoms in the growing child.

d.protist, Toxoplama gondii.

Which of the following series best represents the energy flow in an ecosystem?

d.sun → producer → consumer → metabolic heat

What criteria best characterize membership in the kingdom Protista?

d.the inability to meet the characteristics that define each of the remaining eukaryotic kingdoms

If a disease quickly spreads through a desert and kills moths that are the sole pollinators of long-lived yucca plants, the most likely outcome would be that

d.the yucca plants would not be pollinated and would eventually go extinct.

According to the phylogenetic tree shown below,

d.zygomycetes have an equally close relationship to basidiomycetes and ascomycetes.

In comparing the two communities shown below, community.

A has a higher relative species abundance.

When comparing the peaks on both of the graphs below the lynx population reaches its maximum

a.slightly after the hare population reaches its

At the base of the evolutionary tree of all life is the ________ ancestor.

a.universal

If there are 20,000 kcal available in the primary producer level of an ecosystem, how many kcal would be available in the secondary consumer level?

a.200

In comparing the two communities shown below, community.

b.B has a higher species richness.