Science (M-STEP)

Graphene is, basically, a single atomic layer of graphite; an abundant mineral which is an allotrope of carbon that is made up of very tightly bonded carbon atoms organized into a hexagonal lattice. It has the strongest tensile strength of any discovered material. Which area would this have a major impact?

Building bridges

A model of a specific event during meiosis is shown with various possible combinations. Which statement correctly cites evidence from the model to support the idea that meiosis increases genetic diversity?

Chromosomes can align in metaphase I in multiple possible arrangements in a process called independent assortment.

Which of these CORRECTLY explains one difference between the processes of photosynthesis and respiration?

The Calvin cycle takes place only in the chloroplast.

This flask originally held some copper wire and a clear solution of nitric acid. You and your partner want to know if a chemical reaction occurred. What evidence is there that a chemical change occurred in the flask?

production of a gas and the color change

The ocean acts as a trap for greenhouse gases like carbon dioxide. If no greenhouse gases, like carbon dioxide, were added to the atmosphere which graph represents the trend we would likely experience?

the correct graph is the one that shows over time the ocean would take in more carbon dioxide, and the global temperature would fall.

In a pond, the pollution of water by human-made pollutants, such as oil and grease, can cause chemical, biological, and ecological changes. As plants begin to die and decompose, carbon dioxide is released. What would happen to the fish in the pond?

the fish would die off

What is the action force responsible for seafloor spreading?

the intrusive of magma forced up toward the ocean ridge

The light pattern shown is a result from a beam of light being passed through a single slit. The pattern is created from constructive and destructive interference. This phenomenon is due to

the wave nature of light.

Nuclear decay, shown here, contributes what important form of energy to Earth?

heat

2CO(g) + O2(g) → 2CO2(g) If the reaction occurs in a closed chamber, _________________ will result in a decrease in the reaction rate.

increasing the size of the container

There are many positive feedback loops that accelerate global warming and cause climate change. For example, as polar ice melts due to global warming, there will be __________ sunlight reflected away and consequently, _______________________.

less, surface temperatures will increase

Surface tension for substances is directly related to the intermolecular force strengths for those substances. Determine the correct order for increasing strength of intermolecular forces.

methanol < ethylene glycol < formamide < water

Two containers of liquid are added to one another. The liquids are identical in composition. One container holds 100 milliliters of the liquid and has a temperature of 60°C. The other container has 50 milliliters of the liquid and a temperature of 30°C. What is a reasonable temperature after they are mixed together?

52°C

The function of a gas furnace is to convert the chemical energy of a fuel into thermal energy. The gas furnace in your house has an efficiency of 58 percent with an energy output of 522 BTU from a 900 BTU input of natural gas. If you replace this gas furnace with one that produces an energy output of 481 BTU from a 740 BTU input of natural gas, what is the efficiency of your new furnace?

65%

Brown rabbits have the genotype BB or Bb. White rabbits have the genotype bb. If two brown rabbits, with the genotypes seen in the Punnett square above, have baby rabbits, what is the probability that the baby rabbits will also be brown?

75%

During the past 40 years, close to 20 percent of the Amazon rain forest has been cut down, more than in all the previous 450 years since European colonization began. Scientists predict that an additional 20 percent of the trees will be lost over the next 20 years. The Amazon rainforest, like other rainforests, produces half its own rainfall through the moisture it releases into the atmosphere through transpiration. Eliminate enough of that rain through deforestation, and the remaining trees dry out and die. Other problems result from the deforestation of rainforests. One can be seen here. Deforestation leads to many negative situations on Earth, as illustrated by this satellite image. All BUT ONE is a consequence of the deforestation of the rainforest. That is:

Deforestation leads to a decrease in fossil fuels.

A tree of life depicting the hypothetical phylogeny of the three domains is shown above. At which letter is located the common ancestor that would contain membrane-bound organelles?

Eukaryota

Surgeons have been able to perform remote surgery using fiberoptic cables connected to robotic arms. This provides better healthcare to people in remote areas. What quality of fiberoptic cables led to this healthcare advance?

Fiberoptic cables transmit data rapidly and with very little distortion.

More massive objects have a large gravitational force or weight. Why do heavier objects accelerate to the ground at the same rate as lighter ones?

Heavier objects need a greater force to accelerate according to F=ma.

The carrying capacity of a biological species in an environment is the maximum population size of the species that the environment can sustain indefinitely, given the food, habitat, water, and other necessities available in the environment. What factors would increase a carrying capacity for a population?I. habitat lossII. increase in food sourcesIII. access to clean waterIV. increase in competitionV. increase in diseases

II and III

The dodo bird is now extinct. What factor would not have led to its extinction?

It was well adapted to living on the island of Mauritius.

According to the universe expansion model, objects in the universe are continually moving away from each other. According to the figure above, what evidence would support the universe expansion model?

Light moving away from the Earth would experience a red shift and the wavelengths would get longer.

Solar energy is utilized to convert inorganic carbon, in the form of carbon dioxide, into organic carbon compounds, such as glucose. This is part of the carbon cycle on Earth; a cycle which demonstrates the law of conservation of matter. What process is responsible for initiating this cycle?

Photosynthesis

A negatively charged particle is placed in a uniform electric field directed from South to North. What direction will the particle move?

South

More radiated heat is being reflected back to Earth and less is radiating into space. What is one reason for this change?

The burning of fossil fuels is increasing the production of carbon dioxide.

What is the MOST LIKELY effect on the energy pyramid if all producers are removed from the ecosystem?

The energy pyramid will be completely disturbed.

In a protected grassland preserve, there are herds of antelope and zebra and a pride of fifteen lionesses with cubs. A conservation program for lions plans to move the pride to a national park fifty miles north. What effect would this move have on the stability of this grassland preserve?

The herbivorous animals would initially thrive, but eventual overgrazing would lead to starvation or migration.

Following an activity on Earth's magnetic field, Margot's teacher asked the students to brainstorm and develop a model of the Earth's layers and its magnetic field lines. One group drew this model. How does the students' model add to your understanding of Earth's structure and resulting magnetic field?

The model includes a magnet in the center, representing Earth's magnetic core and includes the magnetic field it generates.

All BUT one of the following is a component of nucleic acids. Nucleic acids DO NOT contain

amino acids.

Why does light refract when it encounters the glass in a lens?

because it slows down, which causes it to bend

Inherited traits are passed down from our parents to us, their offspring, by the information that is coded in our parents'

chromosomes.

The CDM (cold dark matter) is a standard model. The Lambda CDM model contributes to the explanation of the accelerating expansion of the universe observed in light from distant galaxies and the universe. Which statement best describes the early universe?

cosmic inflation

Which layer of the earth contains granite and basalt in the GREATEST abundance?

crust

This reaction progress diagram shows the changes during a chemical reaction and the effects on energy. How has the energy changed from reactants to products?

energy is released

At the heart of the sun, the temperature and pressure is enough to drive ___________ reactions. These reactions release energy from the surface of the sun by emitting light or releasing high energy particles.

fusion

During application of a certain medical device a patient is exposed to a strong magnetic field. The tissues of the body include hydrogen atoms that contain one proton in the nucleus and these protons are always spinning. As a result, these protons produce a tiny magnet field, something like the electrons spiraling around the core of an electromagnet. In a magnet field the hydrogen protons act like tiny toy tops that wobble as they spin. The rate of the wobbling is called resonance. A short pulse of radio waves is sent through the body. When the frequency of the signal is the same as the resonance, the proton flips and spins on its opposite end. To do this the proton absorbs some of the energy of the radio wave. Doctors are able to determine what substance the hydrogen atom is in by monitoring and evaluating the combination of magnetic field strength and radio signal that flips the proton. The steps described are involved in what medical application?

MRI (Magnetic resonance imaging)

Students carry out an experiment to test how white button mushrooms grow best. They begin with identical trays that contain straw, wood chips, and compost, as well as the roots that will form the mushroom caps. The students' experiment and results are described in the table. Which statement is consistent with the students' results?

Mushrooms gain energy by breaking down once-living matter.

The ___________________ is an early theory which states that our solar system was formed by the gravitational collapse of a massive giant cloud.

Nebular Theory

According to the theory of Plate Tectonics, Earth's surface is made up of thin, rigid plates composed of oceanic crust, continental crust, or, in transitional areas, both. These plates are always in motion. The map shows plate motion based on Global Positioning System (GPS) satellite data from NASA. The vectors show direction and magnitude of motion. What is thought to be a powerful source of plate motion?

excess density of the oceanic lithosphere sinking in subduction zones.

The chart shows parts of a human being and a plant, at different levels of organization. Which pair is at the same level of structural organization?

S and X

Using only the information available in the periodic table, consider the elements sulfur and oxygen. From their location on the periodic table, identify the oxidation state and number of valence electrons for sulfur and oxygen. Then use this information to describe their reactivity. Which statement most accurately describes the compound formed by sulfur and oxygen?

Sulfur dioxide, SO2, is covalent, formed by the sharing of electrons between sulphur and oxygen.

If a positively charged particle moves into a magnetic field traveling in a straight line, how would you expect its motion to change?

The particle would travel in a curved path.

The image shows the cone forecast map of a hurricane. Location P is marked in the upper right part of the map. Which statement BEST describes the risk of damage due to the hurricane at P?

The risk is high as P lies near the border of the potential track area.

There are two plant populations (A and B) located in this wetland system. Population A lives within the wetlands, in the lowlands surrounding the pond. This habitat is characterized by high humidity and an abundance of plant species. Population B lives on higher ground; on the hills overlooking the pond and wetland. The plants in Population B are mostly one species of small trees. The transpiration rates of the two populations differ greatly, as seen in the data table. The research group collecting the transpiration data has hypothesized that the relative humidity in each location plays an important role in the transpiration rate. Another group suggested that transpiration rate varies with species and that the populations are composed of completely different species. You are part of the research group that hypothesized that relative humidity played a role in the transpiration differences. What additional evidence might you provide to support your hypothesis?

Population B shows an increased loss of water through transpiration because the environmental conditions are windier and less humid.

Since 1980 global surface temperatures have increased sharply. This is believed to be the Earth's response to increasing concentrations of greenhouse gases, such as carbon dioxide. In 1981 James Hansen, and his colleague at NASA, Andy Lacis, built a simple climate model to simulate how changes in the atmosphere cause Earth's average temperature to change over time that can be seen above. Hansen and Lacis adjusted the inputs to simulate the influence of all known human-made greenhouse gases except carbon dioxide, including CFCs, methane, nitrous oxide, and ozone, to see if their net effect could be felt on a global scale in Earth's climate system. Hansen and Lacis found that the warming effect of all those gases added together is comparable to the warming effect of carbon dioxide alone. On Earth, human activities are changing the natural greenhouse effect. Over the last century the burning of fossil fuels in the forms of coal and oil has increased the concentration of atmospheric carbon dioxide. Remember the combustion of carbon-based products produce carbon dioxide as a by-product. To a smaller extent, the clearing of land for agriculture, industry, and other human activities have increased concentrations of greenhouse gases. The EPA has published a report that indicates what economic sector these emissions come from:Because of the connection between greenhouse gases and climate change, there seems to be a concerted effort to reduce greenhouse gas emissions. What does this second graph, published by the EPA, tell us about how the Hansen and Lacis model will change?

The Hansen and Lacis model will continue as it is now, with an increase in the Earth's average temperature because the EPA model shows no real change in gaseous emissions.

Young stars, just beginning their life in the galaxy, would contain mostly

hydrogen and helium.

Axial tilt is the inclination of the Earth's axis in relation to its plane of orbit around the Sun. Oscillations in the degree of Earth's axial tilt occur on a periodicity of 41,000 years from 21.5 to 24.5 degrees. Today Earth's axial tilt is at 23.5 degrees. With less axial tilt the Sun's solar radiation is more evenly distributed between winter and summer. and it also increases the difference in incoming radiation between the equator and the polar regions. Imagine a smaller degree of axial tilt. This would influence Earth's climate in several ways. Which would not be the result of decreasing the tilt?

less snow fall

The best solution for preventing harm to people and pets from severe hurricanes involves determining and warning residents about which of these?

the hurricane's track and category rating

Conservation biology supports all but one of the following practices.

the introduction of alien species to an area outside their normal range

The picture shows a group of muscle cells in the heart. All of these muscle cells beat in unison to push blood in timing with the rhythm of the heart, at the direction of nearby nerve cells.These muscle cells could best be called a

tissue.