Exam 1
Humans simulate the process of natural selection when they use ________ to develop new varieties of crop plants that better meet the needs of farmers.
artificial selection
Humans are
biotic factors within the biosphere.
In marine ecosystems, net primary productivity tends to be
greater along shorelines where terrestrial nutrients enter the marine environment.
The top of the "S" in an S-shaped curve indicates that the population
has reached its carrying capacity.
Living organisms maintain a constant internal environment by sensing and responding to their internal conditions. This stable maintenance of internal conditions is known as
homeostasis
Both humans and whales evolved from a common ancestor. Although our forelimbs are quite different, they are made of the same bones. This is an example of a(n)
homologous structure.
When scientists generate a single informed, logical, and plausible explanation for a question and observations of the natural world, they are proposing a scientific
hypothesis.
Tails are found
in embryos of a wide variety of organisms, some of which have a tail as adults and others do not.
The Amazon rainforest
is part of the biosphere.
The fossils of organisms that existed when the continents were connected are distributed across ________ continents than the fossils of organisms that evolved after the continents separated.
more
The proteins and DNA of organisms that share a recent common ancestor are ________ the proteins and DNA of organisms that do not share a recent common ancestor.
more similar than
Which of the following are examples of primary producers in a beech-maple woodland?
mosses, grasses, beech trees, maple trees
Clown fish have evolved to live safely between the stinging tentacles of certain sea anemones. The fish receive protection from predators, whereas anemone receive some food from the fish. This relationship is an example of
mutualism
Every healthy human digestive system is home to countless microorganisms. In a normal digestive system, what type of relationship would you say this is?
mutualistic
The result of ________ over evolutionary time spans is that alleles that allow organisms to survive and reproduce at a higher rate than other individuals become more common in the population.
natural selection
Peppered moths are generally light in color and blend into the trunks of the trees they live on. Populations of peppered moths found in areas where soot has blackened the tree trunks are dark in color. This example demonstrates
natural selection.
Into which category would a human be assigned when eating pepperoni pizza?
primary and secondary consumers
A measurement of how common one species is compared to another species is referred to as
relative species abundance.
Which of the following would be abiotic components of an arctic, marine ecosystem?
saltwater, ice, snow, sun, wind, rocks, sand
Evolution is
strongly supported by scientific evidence.
The process that establishes new communities and restores disturbed communities is termed
succession
The process that establishes new communities and restores disturbed communities is termed
succession.
The graph below indicates that global temperatures have
tended to increase, especially in the last 100 years.
A scientific hypothesis must be ________; if not, science cannot evaluate it.
testable
When an isolated population reaches its carrying capacity
the birth rate = the death rate.
Which of the following is NOT a major factor in shaping the climate of a local region?
the dominant herbivorous organisms of a region
Tuna are predatory fish that consume smaller, carnivorous fish that have fed on zooplankton. The zooplankton had fed on phytoplankton. You eat tuna, you are what level of the food chain?
the fifth trophic level
Tuna are predatory fish that consume smaller, carnivorous fish that have fed on zooplankton. The zooplankton had fed on phytoplankton. When you eat tuna, you are consuming what level of the food chain?
the fourth trophic level
Whenever we ________, we are proceeding scientifically.
try to solve a problem by systematically evaluating the plausibility of various solutions
A species of cave beetle that lives in total darkness is blind but has remnants of what looks like eyes. These "eyes" are
vestigial.
In 1978, a drought on the Galapagos Islands caused a reduction in the production of seeds that one of Darwin's finches, a kind of bird, fed upon. This caused a decrease from 1,400 to 200 birds. This population change factor
was density-independent.
By imposing the one-child policy, China's government is attempting to manipulate which of the following factors?
birth rate
Which of the following are likely biotic components of a desert ecosystem?
cacti, sage brush, scorpions, and snakes
Human activities
can alter nutrient cycles on local and global scales.
The maximum population size that can be supported by its habitat is known as
carrying capacity.
Pathogens are considered a special type of parasite because they
cause disease in their hosts.
Observational studies typically point out correlations between aspects of the natural world, but they do not establish solid ________ relationships.
cause-effect
Although the terms climate and weather are often used interchangeably, they are not the same thing. Climate differs from weather in that
climate describes long-term patterns, whereas weather describes short-term fluctuations.
In comparing the two communities shown,
community A has a higher relative species abundance.
Rabbits, foxes, tapeworms, and fungi are all examples of
consumers
Which of these changes would decrease one's food footprint the most?
cooking vegetables instead of steak
In the absence of ________, nutrient recycling within the ecosystem would completely stop.
decomposers
Which of the following is NOT a consequence of climate change?
decreased flooding
The decrease in the availability of food or cover that accompanies increasing population size illustrates the concept of a(n)
density-dependent factor.
A community of organisms together with the physical environment in which they live is known as a(n)
ecosystem
A community of organisms together with the physical environment in which they live is known as a(n)
ecosystem.
The size of a population can be decreased by
emigration.
Ecologists often define an ecosystem by describing how ________ and ________ are acquired and distributed by the biotic community.
energy; nutrients
Areas of the ocean that are very cloudy due to large amounts of stirred sediment or eroded soil are likely to
experience decreased primary productivity levels.
Which of the following symbols represents a mutualistic relationship?
+/+
The carrying capacity for Paramecia caudatum as shown in this figure is
200/ml of medium.
Which of the following has the highest population density?
1,500 oysters living in an area of 1,500 square meters
On average, what percentage of the energy from one trophic level of an energy pyramid is transferred to the next trophic level?
10 percent
This graph shows the growth of a population of Paramecium caudatum. The greatest amount of daily growth occurred when the population was at approximately ________ percent of its carrying capacity.
100
According to the figure shown, human populations began to experience exponential growth around
1800
If there are 50 kcal of energy in the tertiary consumer trophic level, how many kcal would you expect to find in the primary consumer level?
5,000
This graph shows the growth of a population of Paramecium caudatum. The greatest amount of daily growth occurred when the population was at approximately ________ percent of its carrying capacity.
50
Which of the following communities would be considered to have the greatest species richness?
An elk gut with 240 species of microorganisms where 95 percent of the microorganisms are bacteria.
In the diagram below, how do nutrient and energy flow differ?
Energy flow is one-way, whereas nutrients are recycled.
Which of the following is/are part of accepted cell theory?
Every living organism is composed of one or more cells, and all living cells arise from preexisting cells.
Bears have thinner bones than whales. Hippopotami have intermediate bone thickness. What hypothesis does this support?
Hippopotami spend part of their time living in water and part living on land.
What will happen in the future if humans continue to impact natural systems at the same rates as today?
Human societies may experience severe disruptions in the services ecosystems provide that human societies depend on.
A scientific hypothesis must be constructed with which of the following characteristics?
It provides a reasonable explanation to a question and is consistent with current observations; it must also be testable and falsifiable.
The activity of predators has caused their prey to evolve a variety of protective characteristics. How are prey able to acquire new features?
Natural selection acts on genetic variability already present in the prey population.
Victoria, who is 10 years old, wants to be a zoologist when she grows up because she loves animals. So, she decided to begin her training by "doing something scientific." Specifically, she weighed and measured the lengths of all the earthworms she could find in her yard and recorded the data in a notebook. She then made a graph showing the maximum, minimum, and average weights and heights of the earthworms. Was she doing something scientific?
No, because she had no hypothesis to direct her data collection or interpretation.
Recently, beekeepers have noticed an alarming and sudden disappearance of honeybees from their hives. Some beekeepers and environmentalists worry that crops genetically engineered to contain the gene for the Bt insecticidal toxin may be killing the bees. Without data from a scientific experiment, is it reasonable to state that Bt-containing crops are responsible for the loss of honeybees?
No, because there could be some other unknown or unmentioned factor affecting the survival of honeybees.
Once a climax community develops, is it likely to remain that way indefinitely?
No, over long-term timescales climate change will probably occur, causing the community to eventually change.
The figure shown 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 best explains the gradual reduction of the pine?
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.
This figure shows that the human population was small and relatively stable for nearly 12,000 years but has increased dramatically in the past 200 years. How might this increase in population growth be explained?
Prior human populations were at existing carrying capacities but newly developed technologies have raised the carrying capacity and permitted the recent expansion.
Which of the following experiments would help to identify a keystone species?
Remove the suspected species from the area and observe the effects on other community members.
A new species is introduced into a given area. The population size begins to grow slowly, then at a very rapid rate, and finally levels off at a stable number. This growth pattern is best represented by a(n)
S-shaped population curve.
Why do human embryos develop gill slits?
The ancestor of humans had gills.
Which of the following would probably NOT occur if a single species was removed from an ecological community?
The community would cease to exist.
Which of the following statements accurately describes information shown in this figure?
The population density is highest along the eastern coast of China.
Which of the following statements is true?
The scientific method or process can help people make informed medical and environmental decisions.
You are relaxing on an island beach enjoying the warm air and sunshine when you notice the striking pure blue color of the water in the deep crater of the island's bay. The water in the surrounding ocean is more of a green color. Which of the following is a logical hypothesis?
The water in the bay has a low level of phytoplankton while there is a higher concentration of phytoplankton in the surrounding ocean.
Which of the following statements about communities is true?
There can be complex interactions between the organisms that make up a community.
What characteristic is NOT shared by all living organisms?
They make their own energy.
Why do scientists repeat their experiments over and over again?
They must make sure the results were not an accident and that they are repeatable.
Two fossils of the same species are found in both Africa and South America. What does this indicate?
This organism evolved before the separation of Pangaea.
Some whales have teeth as embryos but do not as adults. What is the most likely explanation of this phenomenon?
Whales evolved from organisms that have teeth.
Is it possible for scientists to study events that happened or animals/plants that lived millions of years ago?
Yes. Apply the laws of physics and nature that we know exist today to evaluate the evidence of past events. For example, observe modern animal behavior, structure, and function, and compare them to the structures of fossilized animals to deduce the function of the fossilized structures.
Is it important for scientists to communicate their results to fellow scientists?
Yes. The quality and accuracy of the scientific work can be enhanced by input, further review, and possibly even repetition by other scientists working in the same field.
You are coughing and producing a wheezing sound as you breathe; you also have a fever. You go to the doctor who listens to your chest, takes X-rays of your chest, and determines that you probably have something called croup. Which of the following are the facts in this scenario?
You are coughing, wheezing, and have a fever.
Cutting down trees in a forest can affect the flow of a river. This is an example of
a biotic factor affecting an abiotic factor.
Greenhouse gases warm the planet by
absorbing and reemitting infrared radiation.
Which of the following would best be considered an aspect of climate?
average rainfall
Which of the following types of organisms are commonly single-celled (unicellular)?
bacteria, some fungi (yeast), and many protozoans