HS Sample Set 8, Round 16 from NSB
Which of the following glial cell types makes up the blood-brain barrier? W) Astrocytes X) Oligodendrocytes Y) Radial glia Z) Schwann cells
W: W) Astrocytes
X: X) Oligodendrocytes
Y: Y) Radial glia
Z: Z) Schwann cells
Answer: W) W) Astrocytes
Dopamine, norepinephrine, and epinephrine are all derivatives of what amino acid?
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Identify all of the following three instruments or techniques that could be used to determine the concentration of an unknown solution of acetic acid: 1) titration; 2) potentiostat; 3) ion-exchange column.
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For a second-order kinetic process where 1 molecule of A irreversibly becomes 1 molecule of B, which of the following plots would generate a line? W) Plotting the concentration of A versus time X) Plotting one over the concentration of A versus time Y) Plotting the log of the concentration of A versus time Z) Plotting the exponential of the concentration of A versus time
W: W) Plotting the concentration of A versus time
X: X) Plotting one over the concentration of A versus time
Y: Y) Plotting the log of the concentration of A versus time
Z: Z) Plotting the exponential of the concentration of A versus time
Answer: X) X) Plotting one over the concentration of A versus time
What is the limit as x approaches 3 of \((x^2 - 9)/(x^4 - 81)\)? W) 1 X) 5/4 Y) 5/8 Z) 5/36
W: W) 1
X: X) 5/4
Y: Y) 5/8
Z: Z) 5/36
Answer: Y) Y) 5/8
Indicate all of the following three possible values for \(c\) so that the equation \(2x^2 - 3x + c = 0\) has roots that are irrational: -1; -2; -3.
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A single semiconductor crystal that has been selectively doped with small amounts of phosphorous on one end and aluminum on the other end creates what type of connection?
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Consider a linear temperature scale, J, on which the boiling point of water is 65° J and the freezing point is –15° J. To what temperature in degrees Fahrenheit does –55° J correspond?
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Much of Tibet lies in altitudes above 17,000 ft. At such altitudes, which of the following best approximates the percentage of the atmosphere below the Tibetans? W) 10% X) 50% Y) 90% Z) 99%
W: W) 10%
X: X) 50%
Y: Y) 90%
Z: Z) 99%
Answer: X) X) 50%
Some individual minerals in metamorphic rocks are bounded by their crystal faces. What adjective identifies this type of rock? W) Xenoblastic X) Idioblastic Y) Crystalloblastic Z) Porphyroblastic
W: W) Xenoblastic
X: X) Idioblastic
Y: Y) Crystalloblastic
Z: Z) Porphyroblastic
Answer: X) X) Idioblastic
Which of the following describes the conditions of a process that would be impossible without an energy input? W) ΔG < 0; ΔH < 0; ΔS > 0 X) ΔG > 0; ΔH > 0; ΔS > 0 Y) ΔG < 0; ΔH < 0; ΔS < 0 Z) ΔG > 0; ΔH > 0; ΔS < 0
W: W) ΔG < 0; ΔH < 0; ΔS > 0
X: X) ΔG > 0; ΔH > 0; ΔS > 0
Y: Y) ΔG < 0; ΔH < 0; ΔS < 0
Z: Z) ΔG > 0; ΔH > 0; ΔS < 0
Answer: Z) Z) ΔG > 0; ΔH > 0; ΔS < 0
Which of the following statements is TRUE regarding calorimetry and heating curves? W) Bomb calorimeters directly measure the change in enthalpy of a reaction X) A heating curve plots pressure versus temperature and is divided into three regions Y) Regions depicting a phase change are flat on a heating curve Z) The steeper the slope of a heating curve, the higher the heat capacity of that phase
W: W) Bomb calorimeters directly measure the change in enthalpy of a reaction
X: X) A heating curve plots pressure versus temperature and is divided into three regions
Y: Y) Regions depicting a phase change are flat on a heating curve
Z: Z) The steeper the slope of a heating curve, the higher the heat capacity of that phase
Answer: Y) Y) Regions depicting a phase change are flat on a heating curve
Which of the following vitamins is NOT fat soluble? W) Tocopherol X) Phylloquinone Y) Biotin Z) Calciferol
W: W) Tocopherol
X: X) Phylloquinone
Y: Y) Biotin
Z: Z) Calciferol
Answer: Y) Y) Biotin
Ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) is the most abundant protein on Earth. Which of the following is NOT a reason that plants produce such large quantities of RuBisCO? W) RuBisCO is a slow-acting enzyme X) RuBisCO lacks specificity for carbon Y) RuBisCO is inhibited by carbon dioxide Z) Plants build large aggregate complexes of RuBisCO
W: W) RuBisCO is a slow-acting enzyme
X: X) RuBisCO lacks specificity for carbon
Y: Y) RuBisCO is inhibited by carbon dioxide
Z: Z) Plants build large aggregate complexes of RuBisCO
Answer: Y) Y) RuBisCO is inhibited by carbon dioxide
Graphite is a fantastic electrical conductor. What is its crystal structure? W) Tetragonal X) Planar Y) Octahedral Z) Buckeyballs
W: W) Tetragonal
X: X) Planar
Y: Y) Octahedral
Z: Z) Buckeyballs
Answer: X) X) Planar
What principle of spectroscopy states that electronic transitions generally happen faster than the vibrational timescale and that electronic transitions will only occur if the vibrational wave functions of the two states overlap significantly?
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Evidence of which of the following was gathered from the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) and indicates possible low-grade subsurface metamorphism on Mars? W) Highly folded strata X) Hornfels and greenstone Y) Magnesium-rich carbonates Z) Alteration clays
W: W) Highly folded strata
X: X) Hornfels and greenstone
Y: Y) Magnesium-rich carbonates
Z: Z) Alteration clays
Answer: Z) Z) Alteration clays
In the early stages of formation, river valleys exhibit which of the following characteristics? W) V-shaped cross sections X) Water tables Y) Moraines Z) U-shaped cross sections
W: W) V-shaped cross sections
X: X) Water tables
Y: Y) Moraines
Z: Z) U-shaped cross sections
Answer: W) W) V-shaped cross sections
What is the lateral surface area of a right circular cone with radius 5 and height 12?
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In a 30–60–90 right triangle, the 60° angle is bisected. What is the ratio of the segments into which the bisector divides the opposite leg?
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Name the growth response to generalized mechanical disturbances in plants.
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In plants, what class of ground tissue is responsible for most of the plants’ photosynthesis?
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Which of the following molecules has T-shaped molecular geometry? W) BF₃ X) NF₃ Y) ClF₃ Z) SO₃
W: W) BF₃
X: X) NF₃
Y: Y) ClF₃
Z: Z) SO₃
Answer: Y) Y) ClF₃
An adsorption isotherm apparatus consists of a dosing chamber (30 mL) and a sample chamber initially at 0 torr. Helium is introduced to 600 torr in the dosing chamber, then allowed to expand into the sample chamber until equilibrium at 400 torr. What is the volume of the sample chamber (in mL to two significant figures)?
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What phenomenon, often observed when nuclear waste is stored in water, occurs when charged particles travel through a medium faster than the speed of light in that medium?
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A rocket at rest in deep space accelerates at 50 m/s² for 5 s, coasts 3 s, then decelerates at 2 m/s² to a halt. How far (to two significant figures) does it travel during the deceleration phase?
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Which of the following lavas does not have a modern analog? W) Komatiite X) Natrocarbonatite Y) Phonolite Z) Boninite
W: W) Komatiite
X: X) Natrocarbonatite
Y: Y) Phonolite
Z: Z) Boninite
Answer: W) W) Komatiite
What is the hottest class of brown dwarfs?
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Which of the following amniotic egg structures does NOT match its function? W) Amnion, protects developing embryo in fluid-filled sac X) Yolk sac, stockpiles nutrients Y) Chorion, facilitates gas exchange Z) Allantois, connects yolk to embryo
W: W) Amnion, protects developing embryo in fluid-filled sac
X: X) Yolk sac, stockpiles nutrients
Y: Y) Chorion, facilitates gas exchange
Z: Z) Allantois, connects yolk to embryo
Answer: Z) Z) Allantois, connects yolk to embryo
Which of the following does albumin help to regulate? W) Osmotic pressure X) Electron transport Y) DNA repair Z) Heme maturation
W: W) Osmotic pressure
X: X) Electron transport
Y: Y) DNA repair
Z: Z) Heme maturation
Answer: W) W) Osmotic pressure
There are 50 people in a room: 28 are male and 32 are in college. Twelve are males in college. How many women who are not in college are in the room?
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Set A consists only of positive integers ≤ 100 such that no two elements sum to 149. What is the maximum number of elements in A?
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Which of the following is NOT a role that large-scale batteries could play in a renewable-based power portfolio? W) Frequency modulation X) Peak shaving Y) Load leveling Z) Voltage modulation
W: W) Frequency modulation
X: X) Peak shaving
Y: Y) Load leveling
Z: Z) Voltage modulation
Answer: W) W) Frequency modulation
What term describes quantities that are independent of a system’s path, such as enthalpy and entropy?
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Drift and diffusion both describe particle movement. Which is an example of drift? W) Random thermal motion of holes X) Atoms moving from areas of high concentration to low concentration Y) Electrons moving to the anode Z) Dopants moving into a semiconductor
W: W) Random thermal motion of holes
X: X) Atoms moving from areas of high concentration to low concentration
Y: Y) Electrons moving to the anode
Z: Z) Dopants moving into a semiconductor
Answer: Y) Y) Electrons moving to the anode
Why is titanium dichloride a solid at room temperature, but titanium tetrachloride a liquid? W) The Ti–Cl bond in TiCl₄ has more covalent character X) The Ti–Cl bond in TiCl₄ has more ionic character Y) TiCl₂ forms a molecular solid, TiCl₄ does not Z) More gaseous chlorine lowers TiCl₄’s melting point
W: W) The Ti–Cl bond in TiCl₄ has more covalent character
X: X) The Ti–Cl bond in TiCl₄ has more ionic character
Y: Y) TiCl₂ forms a molecular solid, TiCl₄ does not
Z: Z) More gaseous chlorine lowers TiCl₄’s melting point
Answer: W) W) The Ti–Cl bond in TiCl₄ has more covalent character
What group of orange unsaturated hydrocarbons is primarily synthesized by plants for use as photosynthetic pigments and contains a biologically inactive form of vitamin A?
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Which of the following is true regarding plant ground tissue? W) Parenchyma is mostly responsible for structural support X) Collenchyma consists of dead cells with thick cell walls Y) Sclerenchyma is the most lignified type of ground tissue Z) Sclerenchyma cells can adapt to stress conditions at maturity
W: W) Parenchyma is mostly responsible for structural support
X: X) Collenchyma consists of dead cells with thick cell walls
Y: Y) Sclerenchyma is the most lignified type of ground tissue
Z: Z) Sclerenchyma cells can adapt to stress conditions at maturity
Answer: Y) Y) Sclerenchyma is the most lignified type of ground tissue
Identify all of the following that could be used as n-type dopants in germanium: 1) phosphorous; 2) boron; 3) antimony.
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You throw a ball straight down at 6 m/s from one building; a friend throws one at 16 m/s from another. Both hit the ground with the same speed (g = 10 m/s²). What is the height difference between the buildings?
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Which of the following compounds acts as a catalyst in the production of biodiesel from oils? W) Vegetable oil X) Lye Y) Methanol Z) Copper
W: W) Vegetable oil
X: X) Lye
Y: Y) Methanol
Z: Z) Copper
Answer: X) X) Lye
What quantum mechanical approximation states that nuclei move much more slowly than electrons and thus can be neglected in the molecular Hamiltonian?
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Consider a dihybrid cross for two independently segregating genes. What simple statistical test would you use to determine if the observed gene distribution significantly differs from the expected?
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The first term of a sequence is 2014; each successive term is the sum of the cubes of the digits of the previous term. What is the 100th term?
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Which one of the following statements about the Boltzmann distribution of energy is FALSE? W) Degenerate states have the same energy and will be equally populated X) An exponential increase in population with increasing temperature is predicted Y) More states are significantly populated if level spacings are near kT Z) At T = 0, only the lowest energy state is occupied
W: W) Degenerate states have the same energy and will be equally populated
X: X) An exponential increase in population with increasing temperature is predicted
Y: Y) More states are significantly populated if level spacings are near kT
Z: Z) At T = 0, only the lowest energy state is occupied
Answer: X) X) An exponential increase in population with increasing temperature is predicted
Two moles of Ca(NO₃)₂ are dissolved in 1 kg of water. Using \(K_b = 0.5\,°\mathrm{C/m}\), what is the boiling point of the solution (to the nearest °C)?
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