52 questions
Which human activity most directly causes a significant increase in the amount of carbon dioxide in the atmosphere?
growing corn for food
not using products containing plastics
driving cars long distances
planting large numbers of trees
An immune response is primarily due to the body’s white blood cells recognizing
a hormone imbalance
abiotic organisms
foreign antigens
known antibiotics
In an effort to reduce the number of deaths due to malaria, scientists have successfully introduced a gene into mosquitoes. The gene makes the mosquitoes unable to support the development of the parasite that causes malaria. The technique used to produce this new variety of mosquito is most likely
chromatography
genetic engineering
electrophoresis of genes
selective breeding
The organic compounds that scientists use to cut, copy, and move segments of DNA are
carbohydrates
enzymes
hormones
starches
Which statement most accurately predicts the result of interfering with populations in the web?
Removing the cricket population will have little effect on the balance of the food web.
Removing all the mountain lions from the food web will benefit the ecosystem.
Removing the cricket and rabbit populations would cause the number of trees to decrease.
Removing deer from the food web will affect the rabbit and grass populations.
A factor not shown in the diagram that provides energy for living organisms is
carbon dioxide
water
the Sun
oxygen
Scientists have found a gene that makes a protein called PKG that controls certain behaviors in many types of ants. The soldier ant will help collect food when it has a low level of PKG. When it has a high level of PKG, the soldier ant will protect and defend its colony. Soldier ants that are given PKG are more likely to ignore food sources and attack intruders. Which conclusion can best be made from this information?
PKG protein is synthesized only by the soldier ants.
Genes control which type of amino acids a cell can make.
Eating too much protein makes some organisms very aggressive.
The behavior of soldier ants is controlled in part by the PKG protein.
Genetic researchers have discovered a number of different gene mutations that have led to the development of cancer. These mutations affect how frequently a cell reproduces. Which process would be directly influenced by these mutations?
differentiation of cells in an embryo
meiotic cell division
division of sperm and egg cells
mitotic cell division
Lobsters are crustaceans related to crayfish, crabs, and shrimp. Most lobsters are a reddish-brown color, but on rare occasions, they can be orange, blue, or even multicolored. These color differences can be caused by
genetic variations
different numbers of offspring
overpopulation and excessive resources
the instability of the ecosystem
Which two factors could lead to the evolution of a species over time?
overproduction of offspring and no variation
changes in the genes of body cells and extinction
struggle for survival and fossilization
changes in the genes of sex cells and survival of the fittest
As human red blood cells mature, they lose their nuclei. As a result of this loss, which process would be impossible for mature red blood cells to carry out?
excretion
respiration
reproduction
transport
To clone a mammal, a cloned embryo is often put into an adult female of the same species to continue internal development. The structure in which the embryo will develop is the
ovary
placenta
uterus
egg
Nuclear power plants, which produce electrical energy, use large quantities of water for cooling. Often, small fi sh, larvae, and fish eggs are sucked in along with the cooling water and destroyed. This example illustrates how
industrialization can have positive and negative effects
removal of these organisms has no effect on an ecosystem
direct harvesting increases the natural fish population
energy is generated without producing wastes
Acid rain is a major problem in the Adirondack Mountains. Evidence that acid rain negatively affected the Adirondack ecosystem is that
this rain has increased the amount of water in Adirondack lakes
there has been a decrease in the variety of fish found in Adirondack lakes
the amount of carbon dioxide in the air over the Adirondack Mountains has drastically decreased in recent years
the number of heterotrophic organisms in Adirondack lakes has increased
Which system in a multi-cellular organism functions most like the cytoplasm in a single-celled organism?
immune
reproductive
nervous
circulatory
A common cycle in biology is represented below. The ATP molecule above is commonly used to
actively transport molecules in an organism
diffuse water across a membrane
move molecules from a high to a low concentration
balance the nutrients in an ecosystem
Fat molecules typically contain long chains of carbon atoms. Animals tend to store fats for use when food resources are scarce. This is an advantage to the animal because
much energy can be gained by breaking the bonds between atoms in the fats
fats give off carbon dioxide that can be used by the muscles
amino acids from fat synthesis are more easily digested than carbohydrates
energy can only be created by digesting fats
While looking at the bottom surface of a leaf with a compound light microscope, a student notices pairs of cells with openings between them on the surface of the leaf. The main purpose of these openings and the cells that surround them is
removing excess sugars
synthesis of carbon dioxide
regulating gas exchange
purification of water
An immune response to a usually harmless environmental substance is known as
an antigen
a vaccination
an allergy
a mutation
Scientists at Penn State have sequenced the DNA of the extinct woolly mammoth. The data suggested that the woolly mammoth was more closely related to present-day elephants than previously believed. Which statement could account for the similarities between the woolly mammoth and present-day elephants?
Common gene mutations were caused by agents such as industrial chemicals and radiation.
Present-day species developed from earlier, different species.
Selective breeding results in offspring better able to survive.
Both animals have identical genetic information.
Single-celled organisms are able to maintain homeostasis, even though they lack higher levels of organization such as organs and organ systems, because
single-celled organisms do not carry out the same life processes as multi-cellular organisms
multi-cellular organisms do not rely on tissues or organs to carry out life processes
cell structures work together to maintain homeostasis in single-celled organisms
single-celled organisms are able to coordinate organ functions to maintain homeostasis
Sharks are often followed by smaller fish that eat some of the scraps from the organisms eaten by the shark. These smaller fish are acting as
decomposers
scavengers
producers
herbivores
The photographs below are side-by-side images of twins A and B with identical genetic information. Twin A is a nonsmoker, while twin B is a longtime smoker. The best explanation for the differences in the appearance of the twins is that
twin B is older than twin A
they each inherited half of their DNA from each parent
the expression of genes is influenced by the environment
one twin resembles the mother and the other resembles the father
Under the supervision of experts, certain areas in a nature preserve are regularly exposed to frequent, low-intensity fires. These controlled fires maintain specific populations of plants by directly
increasing the consumption of finite resources
decreasing the carbon dioxide level in the atmosphere
stopping the process of evolution
interfering with the process of ecological succession
An invasive species, the spiny water fl ea, was recently found in a New York lake. These water fleas eat zooplankton, a food also consumed by native fishes. The fleas spread from lake to lake by attaching to fishing lines, anchor ropes, and boats. Which statement best describes the effect of the water fl ea on the lake?
It will not compete with animals in the local food chain.
It will feed on organisms that are important to other species.
The number of water fleas will decrease due to a lack of food.
There will be no effect on native species in the lake.
A stable ecosystem can have high biodiversity because each species in that ecosystem
occupies a different niche
inhabits a different environment
is part of a different community
lives in a different biosphere
Stability within an ecosystem is achieved partially by the presence of organisms that break down important molecules and make them available for other organisms to use. These organisms are
plants
herbivores
scavengers
decomposers
The diagram below represents a feedback mechanism. The hormone referred to in this feedback mechanism is
estrogen
insulin
progesterone
testosterone
After a lake dried up during a severe drought, a section of undisturbed rock layers was exposed. The layers are represented below. This sequence of rock layers best illustrates the concept that
the living and nonliving environment both change over time
it is important to preserve the diversity of species and habitats
new inheritable characteristics can result from the recombining of genes
living organisms have the capacity to produce populations of unlimited size
Some organisms in an ecosystem are represented in the pyramid below. In the pyramid, the arrows labeled X represent
the loss of organisms due to predation
a decrease in photosynthetic organisms
the loss of energy in the form of heat
a decrease in available oxygen
A student designed an experiment to determine if air temperature had an effect on the rate of photosynthesis in corn plants. Which tool is correctly paired with a procedure that could be used during this experiment?
an electronic balance to measure the volume of soil in which each corn plant is grown
a graduated cylinder to measure 30 mL of water for each plant daily
a metric ruler to determine the mass of each plant each week
a Celsius thermometer to determine the pH of the soil
A student designed an experiment to determine if air temperature had an effect on the rate of photosynthesis in corn plants. The independent variable in this experiment is the
air temperature at which the corn plants were grown
amount of carbon dioxide used by the corn plants
volume of oxygen produced by the corn plants
number of corn plants used
The graph shows the number of animals in a population throughout the course of a year. The population migrated into the area at the beginning of 2011. The graph can best be used to illustrate
a food chain
ecological succession
natural selection
carrying capacity
The graph shows the number of animals in a population throughout the course of a year. The population migrated into the area at the beginning of 2011. The approximate number of animals that were found in June 2012 was most likely
16
26
76
86
To prepare for an experiment, ten different sources of food were sterilized and kept in a sterile container. Bacteria of the same species were placed on each of the ten different food sources and kept at 26°C for two days. During this time, bacteria grew in nine of the containers. Based on this observation, the scientist could conclude that
all ten food sources used in the experiment are capable of supporting this species of bacteria
the temperature varied greatly in nine of the containers during this experiment
only the container that failed to grow any bacteria was prepared correctly
this species of bacteria synthesizes enzymes needed to digest the food in nine of the ten containers
The graph below shows three projections for future carbon dioxide (CO2) levels.
— The “Business as usual” line shows CO2 levels if emissions remain at current levels.
— The “Constant 1990 emissions” line shows CO2 levels if emissions are cut to the same level that they were in 1990.
— The “Half 1990 emissions” line shows CO2 levels if emissions are cut to half of the level that they were in 1990.
Which statement is supported by the graph?
Climate change will result in the melting of polar ice caps.
The increase in carbon dioxide levels will cause a decrease in global average temperature.
Human activities have no effect on atmospheric carbon dioxide levels.
Future generations can be affected by the choices of current generations.
Hydrogen peroxide (H2O2) is a toxic compound that is produced by plant and animal cells. These cells also produce the enzyme catalase, which converts H2O2 into water and oxygen gas, preventing the buildup of H2O2. A student designed an experiment to test the effect of an acidic pH on the rate of the reaction of H2O2 with catalase. The data below summarize the outcome of the experiment. Which graph most accurately represents the results obtained by this student?(don't choose the one with the graphs)
1
2
3
4
Hydrogen peroxide (H2O2) is a toxic compound that is produced by plant and animal cells. These cells also produce the enzyme catalase, which converts H2O2 into water and oxygen gas, preventing the buildup of H2O2. A student designed an experiment to test the effect of an acidic pH on the rate of the reaction of H2O2 with catalase. The data below summarize the outcome of the experiment. Which conclusion is valid based upon the data collected by the student?
The change in pH prevents catalase from breaking down water.
Catalase has the greatest activity at a pH of 7.
Oxygen production will increase if more water is added to the reaction.
Catalase caused the greatest production of oxygen at a pH of 3.
Hydrogen peroxide (H2O2) is a toxic compound that is produced by plant and animal cells. These cells also produce the enzyme catalase, which converts H2O2 into water and oxygen gas, preventing the buildup of H2O2. A student designed an experiment to test the effect of an acidic pH on the rate of the reaction of H2O2 with catalase. The data below summarize the outcome of the experiment. The best explanation for the change in catalase activity as the pH changed from 7 to 3 is that
strong acid digests the catalase, causing the reaction rate to increase
the student most likely cooled the H2O2 solution, causing the reaction rate to increase
in acidic solutions, the shape of catalase changes, causing the reaction rate to decrease
decreased oxygen production causes catalase to increase the rate of reaction
Which graph best illustrates the body temperature in an individual maintaining dynamic equilibrium?
1
2
3
4
Federal legislation establishes and updates energy-efficiency standards for consumer products, including refrigerators. The graph shows the average annual energy consumption of similar types of refrigerators and the year they were manufactured. The 2003 Energy Star models of refrigerators use an average of about 450 kilowatt hours of electrical energy annually. Approximately how much energy is saved by these models annually when compared to the models produced in 1972?
500 kilowatt hours
550 kilowatt hours
1500 kilowatt hours
1550 kilowatt hours
Federal legislation establishes and updates energy-efficiency standards for consumer products, including refrigerators. The graph shows the average annual energy consumption of similar types of refrigerators and the year they were manufactured. Which statement best represents an outcome of federal standards that require increasing the energy efficiency of appliances, such as refrigerators?
More technological improvements in appliances can help conserve finite resources.
Increased efficiency of appliances requires greater use of our energy resources.
Newer appliances are manufactured from a greater number of finite resources.
Manufacturing more efficient appliances will reduce the biodiversity of ecosystems.
A student placed a test tube containing elodea (an aquatic plant) and pond water 10 cm from a light source. He observed that the plant gave off bubbles of a gas and counted how many bubbles were released in one minute. He moved the plant farther away from the light source to see if distance from the source made a difference. The data table below shows his results. The gas that was being produced was most likely
carbon dioxide as a product of the process of respiration
carbon dioxide as a product of the process of photosynthesis
oxygen as a product of the process of respiration
oxygen as a product of the process of photosynthesis
Icefish Evolution
Over the last 50 million years, icefish evolved many adaptations that contributed to their success in surviving the decreasing water temperatures of the ocean surrounding Antarctica. For example, they have the ability to produce an antifreeze protein that prevents their blood from freezing in waters that are now below the normal freezing point of fresh water. Scientists have analyzed the icefish DNA and documented genetic changes that gave rise to the antifreeze gene. Their findings are represented in the diagram below. Process X is referred to as
mitosis
mutation
differentiation
meiosis
Icefish Evolution
Over the last 50 million years, icefish evolved many adaptations that contributed to their success in surviving the decreasing water temperatures of the ocean surrounding Antarctica. For example, they have the ability to produce an antifreeze protein that prevents their blood from freezing in waters that are now below the normal freezing point of fresh water. In addition to the appearance of the antifreeze gene, icefish have also been found to have DNA sequences similar to the DNA sequences in hemoglobin genes of other fish species. However, these DNA sequences are not complete and therefore not functional in icefish. This evidence makes it likely that
icefish ancestors had hemoglobin
icefish will soon produce offspring with hemoglobin
hemoglobin is a molecule made by some fish that do not have genes for it
soon all fish will stop producing hemoglobin
Green sea slugs are animals that live in water and have developed the ability to produce their own chlorophyll. These creatures can also pass this ability to make chlorophyll to their offspring. Once the offspring have one meal of algae, they are able to make food using sunlight. This one meal provides the baby slugs with the chloroplasts needed to make use of the chlorophyll, and they are able to produce their own food in the future. The best explanation for why sea slugs are able to pass on this ability to make food to their offspring is that
the gene for making algae is in all their body cells
the environment causes the slugs to become green
making food is beneficial, so the slugs needed to mutate
the gene for chlorophyll production is part of their DNA
The diagram below represents one of many microscopic air sacs in a human lung. The alveolus (air sac) is the place where oxygen (O2) and carbon dioxide (CO2) move into or out of the blood, as represented in the diagram. Which statement best explains why these gases are able to move in the directions shown in the diagram?
The CO2 moves out of the capillary and into the alveolus to make more room for the blood to carry O2.
The O2 is needed by the cells, so it is actively transported into the blood. The CO2, which is not needed, is actively transported out of the blood.
The blood coming to the lungs is low in CO2 and high in O2, so the gases each diffuse from a lower to a higher concentration in this area.
The blood coming to the lungs is high in CO2 and low in O2, so the gases each diffuse from a higher to a lower concentration in this area.
During the process of chromosome replication, a genetic error occurs. As a result, a sequence of events occurs as described below.
Event A: a protein with a new sequence of amino acids is produced
Event B: a DNA strand with an altered base sequence is formed
Event C: a new inheritable trait is expressed in an organism
Event D: an mRNA strand with a new sequence of bases is synthesized
The usual order in which these events would occur is
B — D — A — C
B — D — C — A
D — A — B — C
D — C — B — A
The evolutionary tree below represents possible relationships between several species of plants. According to the tree, species B and C are more closely related to each other than to species A. Which gel electrophoresis diagram would best support this statement?(look at the diagrams, don pick the diagrams)
1
2
3
4
The evolutionary tree below represents possible relationships between several species of plants. In addition to analyzing DNA, what other evidence could be used to best support the evolutionary relationship between species B and C?
Species B and C live in the same ecosystem.
Species B and C require the same amount of sunlight.
Species B and C possess many of the same enzymes.
Species B and C grow to the same maximum height as species A.
In his journey to the Galapagos Islands, Charles Darwin was amazed by the variation in the characteristics of plants and animals he encountered. In any habitat, food can be limited and the types of foods available may vary. One year, there was no rain on these islands. Many plants failed to bloom and produced no new seeds. This left mostly large, tough seeds for the finches to eat. The different tools (such as spoons, chopsticks, or pliers) used during The Beaks of Finches laboratory activity represented variations in
feeding adaptations
seed size
finch migration
island ecosystems
Respiratory Rates
A student completed a lab activity that demonstrated the connection between pulse rate, heart rate, and fl ow of blood during exercise. She left her class wondering if there is a connection between breathing rate and exercise. With the help of her track coach, she conducted an investigation to try and find an answer to her question. In the investigation, the respiratory rates of thirty athletes were measured before any exercise. To measure their rates, they counted the number of times they took a breath in one minute. Then, they ran one lap around the track, and their respiratory rates were determined again. Finally, they ran two laps around the track and checked their respiratory rates one last time. All of their data were recorded, and the averages were calculated. The data table shows the information obtained in this investigation. During this activity, what was the purpose of finding the respiratory rates of the students at rest?
to determine if the students were healthy
to practice using the timer
to use as a comparison
to use as the variable