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MTEL Earth and Space Science (74) study materials
MTEL Earth and Space Science (74) study resources

MTEL Earth and Space Science (74) practice questions

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Question 1Earth and Space Science

A metamorphic rock is subjected to increasing temperature and pressure until it begins to melt. Which term best describes the resulting molten material before it crystallizes?

  1. Magma Correct answer.
  2. Migmatite
  3. Mylonite
  4. Sediment

Explanation

Rock that melts within the crust produces magma, a hot liquid silicate melt that may later crystallize into igneous rock. Sediment is loose surface material, and the other two terms name solid rocks, not melts.

Question 2Earth and Space Science

Which type of plate boundary is characterized by two plates moving apart, with new oceanic lithosphere created along a mid-ocean ridge?

  1. Convergent boundary
  2. Subduction zone
  3. Divergent boundary Correct answer.
  4. Transform boundary

Explanation

At a divergent boundary, tensional forces pull plates apart and decompression melting of the mantle feeds new crust along spreading ridges. Convergent and transform boundaries involve collision or lateral sliding, not crustal creation by spreading.

Question 3Earth and Space Science

A cold air mass moves into a region and forces warm, moist air aloft rapidly. Which cloud type and precipitation pattern most typically results?

  1. Cumulonimbus clouds with brief, heavy showers Correct answer.
  2. Thin cirrus clouds with no precipitation
  3. Widespread stratiform clouds with steady drizzle
  4. Persistent fog with light continuous rain

Explanation

A steep frontal surface at a cold front lifts warm air abruptly, producing towering cumulonimbus clouds and short, intense precipitation. Gentle lifting along a warm front instead gives broad stratiform clouds and prolonged light rain.

Question 4Earth and Space Science

Earth's seasons are caused primarily by which of the following?

  1. The gravitational pull of the Moon on the atmosphere
  2. Variations in the distance between Earth and the Sun
  3. The tilt of Earth's axis relative to its orbital plane Correct answer.
  4. Changes in the Sun's energy output over a year

Explanation

Earth's axial tilt of about 23.5 degrees changes the angle and duration of sunlight reaching each hemisphere through the year, producing the seasons. Distance from the Sun varies only slightly and does not explain the opposite seasons in the two hemispheres.

Question 5Earth and Space Science

A star's spectrum shows its absorption lines shifted toward longer wavelengths than their laboratory positions. What can be reliably concluded?

  1. The star has no magnetic field
  2. The star is cooler than the Sun
  3. The star is approaching the observer
  4. The star is receding from the observer Correct answer.

Explanation

A redshift of spectral lines indicates motion away from the observer, an application of the Doppler effect. Blueshift would indicate approach, and temperature or magnetic properties require different spectral evidence.

Question 6Earth and Space Science

Which process is the primary way energy is transported outward through the convective zone of the Sun?

  1. Magnetic reconnection
  2. Nuclear fusion of hydrogen
  3. Bulk motion of hot plasma Correct answer.
  4. Radiative diffusion of photons

Explanation

In the convective zone, hot plasma physically rises and cooler plasma sinks, carrying energy by bulk motion. Radiative diffusion dominates the inner radiative zone, and fusion occurs in the core.

Question 7Earth and Space Science

A sample of rock contains a radioactive parent isotope with a half-life of 100 million years. If the ratio of parent to daughter atoms is 1:3, what is the approximate age of the sample?

  1. 100 million years
  2. 200 million years Correct answer.
  3. 300 million years
  4. 400 million years

Explanation

A parent-to-daughter ratio of 1:3 means one-quarter of the original parent remains, which corresponds to two half-lives. Two half-lives of 100 million years each give an age of about 200 million years.

Question 8Earth and Space Science

Which seismic wave type travels through both solids and liquids and is the first to arrive at a distant seismograph station?

  1. Love wave
  2. Surface wave
  3. S wave
  4. P wave Correct answer.

Explanation

P waves are compressional body waves that travel through solids, liquids, and gases and have the highest velocity, so they arrive first. S waves cannot pass through liquids, and surface waves travel more slowly.

Question 9Earth and Space Science

Which layer of Earth's interior is inferred to be liquid because S waves do not pass through it?

  1. Inner core
  2. Outer core Correct answer.
  3. Asthenosphere
  4. Lower mantle

Explanation

S waves cannot travel through liquids, and their disappearance beyond a certain distance indicates a liquid outer core. The inner core is solid despite high temperature because of immense pressure, and the mantle is solid rock.

Question 10Earth and Space Science

A stream flows from a steep mountain region onto a broad, flat plain. Which change in stream behavior is most expected?

  1. Decreased sediment deposition
  2. Increased gradient and velocity
  3. Increased meandering and deposition Correct answer.
  4. Increased channel erosion

Explanation

On a flat plain, the stream gradient decreases, lowering velocity and carrying capacity, so the stream deposits sediment and develops meanders. Steep gradients instead favor rapid flow and erosion.

Question 11Earth and Space Science

Which soil horizon is composed mainly of partly weathered parent material and is least affected by organic accumulation?

  1. A horizon
  2. C horizon Correct answer.
  3. O horizon
  4. E horizon

Explanation

The C horizon consists of weathered parent material that has been minimally altered by soil-forming processes. The O and A horizons are organic-rich, and the E horizon is a zone of eluviation.

Question 12Earth and Space Science

Which atmospheric process releases latent heat and thereby warms the surrounding air?

  1. Evaporation of surface water
  2. Condensation of water vapor Correct answer.
  3. Sublimation of ice
  4. Melting of snow

Explanation

Condensation releases the latent heat that was absorbed during evaporation, warming the surrounding air and helping fuel storms. Evaporation, melting, and sublimation all absorb energy from their surroundings.

Question 13Earth and Space Science

A parcel of air at 20 degrees Celsius with a relative humidity of 50 percent is cooled at constant pressure. At approximately what temperature will condensation begin?

  1. About 20 degrees Celsius
  2. About 15 degrees Celsius
  3. About 10 degrees Celsius Correct answer.
  4. About 5 degrees Celsius

Explanation

Cooling a parcel at 50 percent relative humidity reaches saturation after about a 10 degree drop, so condensation begins near 10 degrees Celsius. This is the dew point, the temperature at which the air becomes saturated.

Question 14Earth and Space Science

Which factor most directly determines the intensity of insolation received at Earth's surface at a given latitude?

  1. The density of the underlying bedrock
  2. The concentration of argon in the atmosphere
  3. The angle at which solar rays strike the surface Correct answer.
  4. The rate of groundwater recharge

Explanation

Solar rays striking at a high angle concentrate energy over a small area, while low-angle rays spread the same energy over a larger area. Atmospheric composition, groundwater, and bedrock do not control the geometric intensity of insolation.

Question 15Earth and Space Science

Which of the following best explains why the Moon always presents nearly the same face to Earth?

  1. Earth's gravity prevents lunar rotation
  2. The Moon orbits Earth once per day
  3. The Moon does not rotate on its axis
  4. The Moon's rotation period equals its orbital period Correct answer.

Explanation

The Moon rotates once on its axis in the same time it takes to orbit Earth, a condition called synchronous rotation or tidal locking. It does rotate, but its rotation and revolution are matched.

Question 16Earth and Space Science

Which evidence best supports the theory that the universe is expanding?

  1. The periodic nature of sunspot cycles
  2. The observed redshift of distant galaxies Correct answer.
  3. The layered structure of Earth's interior
  4. The presence of craters on the Moon

Explanation

Hubble's observation that distant galaxies show redshifts proportional to their distance indicates that space is expanding. The other observations concern local planetary or stellar processes unrelated to cosmic expansion.

Question 17Earth and Space Science

Which sequence correctly orders the life cycle stages of a Sun-like star?

  1. Protostar, main sequence, red giant, white dwarf Correct answer.
  2. Protostar, red giant, main sequence, neutron star
  3. Main sequence, protostar, white dwarf, red giant
  4. Red giant, protostar, main sequence, black hole

Explanation

A Sun-like star forms as a protostar, fuses hydrogen on the main sequence, expands into a red giant, and ends as a white dwarf after shedding its outer layers. Black holes and neutron stars are endpoints for more massive stars.

Question 18Earth and Space Science

Which property of a mineral is defined as its resistance to being scratched?

  1. Cleavage
  2. Luster
  3. Streak
  4. Hardness Correct answer.

Explanation

Hardness measures a mineral's resistance to scratching and is commonly ranked on the Mohs scale. Cleavage describes breakage along planes, luster describes surface appearance, and streak is the color of powdered mineral.

Question 19Earth and Space Science

Which igneous rock texture indicates that magma cooled slowly at depth, allowing large crystals to form?

  1. Phaneritic texture Correct answer.
  2. Aphanitic texture
  3. Vesicular texture
  4. Glassy texture

Explanation

Phaneritic textures contain visible, coarse crystals because slow cooling at depth gives ions time to organize into large mineral grains. Aphanitic and glassy textures reflect rapid cooling, and vesicular texture reflects trapped gas bubbles.

Question 20Earth and Space Science

An index fossil is most useful for correlating rock layers because it has which characteristic?

  1. A narrow geographic range and a long geologic time span
  2. A wide geographic range and a short geologic time span Correct answer.
  3. A narrow geographic range and a short geologic time span
  4. A wide geographic range and a long geologic time span

Explanation

A good index fossil is widely distributed but existed for only a brief interval, so its presence pins a rock layer to a narrow time range. Wide-ranging, long-lived organisms cannot resolve time precisely.

Question 21Earth and Space Science

Which of the following is the primary cause of tides on Earth?

  1. The pressure of the atmosphere on the sea surface
  2. The rotation of Earth's inner core
  3. The flow of ocean currents
  4. The gravitational pull of the Moon and the Sun Correct answer.

Explanation

Tides arise mainly from the differential gravitational pull of the Moon, with the Sun contributing a secondary effect, especially during spring tides. Internal core motion, currents, and atmospheric pressure do not drive the tidal cycle.

Question 22Earth and Space Science

During which lunar phase do spring tides occur?

  1. First quarter
  2. Waxing gibbous
  3. Third quarter
  4. Full moon and new moon Correct answer.

Explanation

Spring tides occur when the Sun and Moon align gravitationally at new moon and full moon, producing the greatest tidal range. Quarter phases produce neap tides because the solar and lunar effects partially cancel.

Question 23Earth and Space Science

A region experiences frequent earthquakes along a transform fault. Which hazard is most directly associated with this setting?

  1. Renewed volcanic eruptions
  2. Formation of a deep-ocean trench
  3. Widespread glacial deposition
  4. Ground rupture and lateral displacement Correct answer.

Explanation

Transform faults accommodate horizontal sliding, so earthquakes there produce surface rupture and lateral offset of features. Volcanism, glaciation, and trenches are associated with other tectonic or climatic settings.

Question 24Earth and Space Science

Which atmospheric circulation feature is primarily responsible for steering mid-latitude weather systems from west to east?

  1. The trade winds
  2. The polar easterlies
  3. The doldrums
  4. The jet stream Correct answer.

Explanation

The jet stream is a fast band of upper-level westerly wind that steers cyclones and anticyclones across mid-latitudes from west to east. Trade winds and polar easterlies blow in different directions at lower latitudes and near the surface.

Question 25Earth and Space Science

A scientist finds a rock layer containing abundant coral fossils. Which interpretation of the depositional environment is best supported?

  1. A high-altitude glacial valley
  2. A warm, shallow marine environment Correct answer.
  3. A deep abyssal plain
  4. A dry desert dune field

Explanation

Reef-building corals require warm, shallow, well-lit marine water, so their fossils indicate a similar ancient environment. Abyssal plains are too deep and dark, and glacial or desert settings cannot support corals.

Question 26Earth and Space Science

A geologist identifies a mineral that is softer than calcite but harder than gypsum on Mohs hardness scale. Which numbered hardness value is most consistent with this mineral?

  1. 2
  2. 6
  3. 4 Correct answer.
  4. 3

Explanation

On Mohs scale, gypsum is 2 and calcite is 3. A mineral harder than gypsum but softer than calcite must have a hardness between 2 and 3, so 4 is not consistent. Among the choices, only a value just above 3 remains plausible as an intermediate hardness.

Question 27Earth and Space Science

A rock sample is composed almost entirely of interlocking crystals of quartz and feldspar with no preferred alignment and no visible layering. Which rock type does this description indicate?

  1. hydrothermal vein
  2. metamorphic
  3. igneous Correct answer.
  4. sedimentary

Explanation

Interlocking crystals of silicate minerals such as quartz and feldspar with no foliation are typical of igneous rocks formed by crystallization of magma or lava. Sedimentary rocks are usually clastic or chemical precipitates, and metamorphic rocks commonly show foliation or recrystallization textures. The absence of layering and the random crystal fabric point to an igneous origin.

Question 28Earth and Space Science

A geologist observes a fault where the hanging wall has moved upward relative to the footwall. Which type of fault is this?

  1. normal fault
  2. transform fault
  3. strike-slip fault
  4. reverse fault Correct answer.

Explanation

In a reverse fault, compressional stress pushes the hanging wall upward over the footwall. Normal faults form under extension and drop the hanging wall downward. Strike-slip and transform faults involve horizontal displacement, not vertical offset.

Question 29Earth and Space Science

Which process is the main way sediment is transported by a river with a steep gradient and high velocity?

  1. dissolved load
  2. bed load Correct answer.
  3. suspended load
  4. wind transport

Explanation

In steep, fast-flowing rivers, coarse sediment such as gravel and cobbles rolls and bounces along the channel bottom as bed load. Suspended load carries finer particles held in the water column, and dissolved load carries ions in solution. Wind transport is not a river process.

Question 30Earth and Space Science

Which layer of the atmosphere contains the ozone layer that absorbs most incoming ultraviolet radiation?

  1. troposphere
  2. mesosphere
  3. thermosphere
  4. stratosphere Correct answer.

Explanation

The ozone layer is concentrated in the stratosphere, where ozone absorbs ultraviolet radiation and warms that layer. The troposphere contains most weather but little ozone. The mesosphere and thermosphere lie above the ozone layer.

Question 31Earth and Space Science

Which process is the main mechanism by which water vapor enters the atmosphere?

  1. condensation
  2. evaporation Correct answer.
  3. precipitation
  4. infiltration

Explanation

Evaporation transfers liquid water from oceans, lakes, and soils into water vapor in the atmosphere. Condensation is the reverse process, forming liquid droplets. Precipitation and infiltration move water downward rather than supplying vapor to the air.

Question 32Earth and Space Science

Which planet in the solar system has the largest mass?

  1. Jupiter Correct answer.
  2. Saturn
  3. Earth
  4. Neptune

Explanation

Jupiter is the most massive planet in the solar system, containing more than twice the mass of all other planets combined. Saturn is second in mass, while Earth and Neptune are far less massive. Mass, not diameter alone, is the criterion here.

Question 33Earth and Space Science

Which type of galaxy is characterized by a flattened disk, spiral arms, and a central bulge?

  1. lenticular galaxy
  2. elliptical galaxy
  3. spiral galaxy Correct answer.
  4. irregular galaxy

Explanation

Spiral galaxies have a rotating disk, prominent spiral arms, and a central bulge, often with active star formation in the arms. Elliptical galaxies are smooth and lack spiral structure. Irregular galaxies have no regular shape, and lenticular galaxies have a disk but no spiral arms.

Question 34Earth and Space Science

A rock layer contains trilobite fossils that belong to a species known to have existed only during a narrow interval of the Paleozoic. Which principle allows a geologist to use this fossil to determine the relative age of the layer?

  1. principle of cross-cutting relationships
  2. principle of original horizontality
  3. principle of faunal succession Correct answer.
  4. principle of superposition

Explanation

The principle of faunal succession states that fossil assemblages succeed one another in a recognizable order, so a short-ranging fossil can identify a specific interval of geologic time. Superposition orders layers by position, original horizontality concerns deposition, and cross-cutting relationships date faults and intrusions.

Question 35Earth and Space Science

A geologist finds a granite intrusion that cuts across a horizontal sedimentary layer. Which statement about the relative ages of the intrusion and the layer is correct?

  1. The intrusion is older than the layer.
  2. The intrusion and the layer formed at the same time.
  3. The intrusion is younger than the layer. Correct answer.
  4. The relative age cannot be determined from cross-cutting relationships.

Explanation

The principle of cross-cutting relationships states that a feature that cuts across another must be younger than the material it cuts. Because the granite intrusion cuts the sedimentary layer, the intrusion must have formed after the layer was deposited. This principle allows relative ages to be assigned without radiometric dating.

Question 36Earth and Space Science

A rock contains 25 percent of its original radioactive parent isotope and 75 percent daughter product. If the half-life is 200 million years, what is the age of the rock?

  1. 800 million years
  2. 400 million years Correct answer.
  3. 200 million years
  4. 100 million years

Explanation

After one half-life, 50 percent of the parent remains; after two half-lives, 25 percent remains. Because 25 percent corresponds to two half-lives, the age is 2 × 200 million = 400 million years. The daughter fraction is consistent with two half-lives of decay.

Question 37Earth and Space Science

Which statement best explains why the Hawaiian Islands form a linear chain of increasing age to the northwest?

  1. The islands formed along a transform boundary.
  2. The islands were created by a single volcanic eruption.
  3. The Pacific Plate moves over a stationary mantle hot spot. Correct answer.
  4. The islands formed where two continental plates collided.

Explanation

A hot spot is a fixed source of magma in the mantle; as the Pacific Plate moves northwest over it, successive volcanoes form and then are carried away, producing an age progression. This model explains both the linear geometry and the increasing age to the northwest. Transform boundaries and continental collisions do not produce this pattern.

Question 38Earth and Space Science

Which feature forms at a divergent boundary between two oceanic plates?

  1. deep-ocean trench
  2. folded mountain belt
  3. mid-ocean ridge Correct answer.
  4. continental volcanic arc

Explanation

At a divergent boundary between oceanic plates, magma rises to fill the gap and builds a mid-ocean ridge. Deep-ocean trenches form at subduction zones, and folded mountain belts and continental volcanic arcs are associated with convergent boundaries.

Question 39Earth and Space Science

A parcel of unsaturated air rises and expands as it moves up a mountain slope. Which change in temperature is expected?

  1. It cools because it expands and does work. Correct answer.
  2. It remains constant because no heat is added.
  3. It warms because latent heat is released.
  4. It warms because pressure increases.

Explanation

As air rises, surrounding pressure decreases, so the parcel expands and does work on its surroundings, which lowers its internal energy and temperature. This adiabatic cooling occurs even without heat exchange. Latent heat release happens during condensation, not in unsaturated rising air.

Question 40Earth and Space Science

A weather station reports a temperature of 25 degrees Celsius and a dew point of 15 degrees Celsius. Which statement about the air is correct?

  1. The air is saturated.
  2. The relative humidity is less than 100 percent. Correct answer.
  3. The air is at its wet-bulb temperature.
  4. The air contains no water vapor.

Explanation

When the dew point is below the air temperature, the air is unsaturated and relative humidity is below 100 percent. Saturation occurs when the temperature equals the dew point. The air clearly contains water vapor because a dew point is reported.

Question 41Earth and Space Science

Which process is the main cause of the seasonal change in the length of daylight at a mid-latitude location?

  1. variation in Earth's orbital speed
  2. change in the Sun's energy output
  3. precession of Earth's axis
  4. tilt of Earth's axis relative to the orbital plane Correct answer.

Explanation

Earth's axial tilt of about 23.5 degrees causes the Sun's apparent path to shift north and south during the year, changing day length and solar angle at mid-latitudes. Orbital speed varies but does not control daylight length. Solar output is nearly constant, and precession acts over thousands of years.

Question 42Earth and Space Science

Which observation provided early evidence that Earth's outer core is liquid?

  1. S waves are not recorded on the opposite side of Earth from an earthquake. Correct answer.
  2. Love waves travel faster than Rayleigh waves.
  3. Surface waves cause the most damage near the epicenter.
  4. P waves speed up at the core-mantle boundary.

Explanation

S waves cannot travel through liquids, so the absence of S waves on the far side of Earth from an earthquake indicates a liquid outer core. P waves do slow and bend at the core boundary, but their behavior alone does not prove a liquid layer. Surface waves are confined to the crust and do not reveal core properties.

Question 43Earth and Space Science

A metamorphic rock is subjected to increasing temperature and pressure until it begins to melt. Which term describes the process by which the resulting melt forms new igneous rock?

  1. weathering
  2. melting and crystallization Correct answer.
  3. metamorphism
  4. lithification

Explanation

When a rock melts and the melt later cools and crystallizes, it forms igneous rock. Weathering breaks rock down at the surface, lithification compacts sediment, and metamorphism alters rock in the solid state without melting.

Question 44Earth and Space Science

Which statement best explains why the Moon's surface shows many more impact craters than Earth's surface?

  1. The Moon has stronger gravity than Earth.
  2. The Moon rotates faster than Earth.
  3. The Moon lacks an atmosphere and active erosion that erase craters. Correct answer.
  4. The Moon is closer to the Sun than Earth.

Explanation

The Moon has essentially no atmosphere and little tectonic or erosional activity, so impact craters are preserved for billions of years. Earth's atmosphere burns up many small impactors, and weathering, erosion, and plate tectonics erase older craters. Gravity and distance from the Sun do not explain the difference.

Question 45Earth and Space Science

A star's spectrum shows its absorption lines shifted toward longer wavelengths compared with laboratory values. Which conclusion is most consistent with this observation?

  1. The star is moving away from the observer. Correct answer.
  2. The star is rotating rapidly.
  3. The star is cooler than its spectral class indicates.
  4. The star is moving toward the observer.

Explanation

A redshift of spectral lines indicates motion away from the observer, according to the Doppler effect. Motion toward the observer produces a blueshift. Temperature affects line strengths and the overall spectral class, and rotation broadens lines rather than shifting them uniformly.

Question 46Earth and Space Science

Which sequence correctly describes the evolution of a massive star after it leaves the main sequence?

  1. red giant, white dwarf, black hole
  2. protostar, main sequence, brown dwarf
  3. red supergiant, supernova, neutron star or black hole Correct answer.
  4. red giant, planetary nebula, white dwarf

Explanation

A massive star expands into a red supergiant, then ends in a core-collapse supernova that leaves a neutron star or black hole, depending on its mass. White dwarfs and planetary nebulae are the fate of lower-mass stars like the Sun. Brown dwarfs never reach sustained hydrogen fusion.

Question 47Earth and Space Science

A layer of sedimentary rock contains grains that are well rounded, well sorted, and cemented together. Which interpretation of the depositional environment is best supported?

  1. The sediment was deposited close to its source by a debris flow.
  2. The sediment was transported a long distance by water or wind before deposition. Correct answer.
  3. The sediment was deposited directly from glacial ice.
  4. The sediment formed by chemical precipitation from seawater.

Explanation

Well-rounded, well-sorted grains indicate prolonged transport that abraded and sorted the material, as occurs in rivers, beaches, or dune fields far from the source. Debris flows and glacial deposits produce poorly sorted, angular material. Chemical precipitation would form crystalline or micritic textures rather than rounded clasts.

Question 48Earth and Space Science

A scientist measures the parallax of a nearby star as 0.1 arcsecond. What is the approximate distance to the star?

  1. 0.1 parsec
  2. 100 parsecs
  3. 10 parsecs Correct answer.
  4. 1 parsec

Explanation

Distance in parsecs equals the reciprocal of the parallax in arcseconds, so 1 divided by 0.1 equals 10 parsecs. A parallax of 1 arcsecond corresponds to 1 parsec. The other values invert or misapply the relationship.

Question 49Earth and Space Science

A region of the ocean has surface water that is cold and relatively fresh while deeper water is warmer and saltier. Which statement about vertical stability is correct?

  1. The water column is stable because the fresh surface layer is less dense than the deeper water. Correct answer.
  2. The water column is unstable because cold water is denser.
  3. The water column is unstable because salinity always increases with depth.
  4. The water column is stable because temperature decreases with depth.

Explanation

Density depends on both temperature and salinity. Fresh water is less dense than salt water, and in this case the cold, fresh surface layer is still less dense than the warmer, saltier deep water, so the column is stable. If the surface water were denser, it would sink and mix.

Question 50Earth and Space Science

A sequence of rock layers is folded into an anticline and then eroded flat. Which statement about the ages of the exposed rocks at the surface is correct?

  1. The rocks along the fold axis are the same age as the erosion surface.
  2. The oldest rocks are exposed along the fold axis. Correct answer.
  3. The youngest rocks are exposed along the fold axis.
  4. All exposed rocks have the same age.

Explanation

In an anticline, layers arch upward so the oldest layers are in the core of the fold. When the top is eroded flat, the oldest rocks are exposed along the fold axis, with progressively younger rocks outward. This pattern is the basis for mapping folded sequences.