HS Sample Set 15, Round 9 from NSB
What is the term for the bright head of a comet?
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Place the following four planets in order of increasing atmospheric pressure at the surface: 1) Mercury; 2) Venus; 3) Earth; 4) Mars.
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Chemists at Brookhaven National Lab are studying the protein BADC, which inhibits the rate-limiting step of fatty acid synthesis in plants. BADC inhibits this process when levels of fats in the cell are already high. In glycolysis, which of the following has the role most analogous to BADC? W) Citrate X) AMP Y) Epinephrine Z) Phosphofructokinase-1
W: W) Citrate
X: X) AMP
Y: Y) Epinephrine
Z: Z) Phosphofructokinase-1
Answer: W) W) Citrate
Identify all of the following three statements that are true regarding metal corrosion: 1) Rust is formed by corrosion; 2) The galvanic series indicates a metal’s relative likelihood to corrode; 3) Dissolved sulfides accelerate metal corrosion.
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Identify all of the following four solutes in 0.05 molal aqueous solutions that would be expected to display a van’t Hoff factor greater than two: 1) Sodium chloride; 2) Magnesium chloride; 3) Glucose; 4) Magnesium sulfate.
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Order the following four compounds in order of increasing boiling point: 1) Iodine; 2) Water; 3) Bromine; 4) Ammonia.
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RLC circuits are known to have a resonant frequency that is dependent on the inductance and capacitance of the circuit. At this frequency, what aspect of the oscillating current is maximized?
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You push horizontally with a 20-newton force on a four-kilogram object initially at rest. After pushing it for a distance of 50 centimeters, in meters per second, what is its speed?
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Saddle, hinge, and ball-and-socket are all types of what structures in the body?
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Order the following three clades chronologically in the order that they first originated: 1) Mammals; 2) Angiosperms; 3) Insects.
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What is the arc length of a sector of a circle with radius 8 and central angle \(\tfrac{7\pi}{4}\)?
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What is the remainder when \(2x^5 - 3x^4 - 4x^3 + 7x - 3\) is divided by the binomial \(x + 2\)?
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Under which of the following sets of temperature and pressure conditions would contact metamorphism occur? W) 800 °C, 0.5 kilobars X) 500 °C, 6 kilobars Y) 400 °C, 10 kilobars Z) 100 °C, 12 kilobars
W: W) 800 °C, 0.5 kilobars
X: X) 500 °C, 6 kilobars
Y: Y) 400 °C, 10 kilobars
Z: Z) 100 °C, 12 kilobars
Answer: W) W) 800 °C, 0.5 kilobars
Which of the following statements about lava is NOT correct? W) Rhyolitic lava has a lower melting temperature than basaltic lava X) Basaltic lava extrusion is typically explosive Y) Andesitic lava has intermediate silica content Z) Rhyolitic lava typically flows more slowly than basaltic lava
W: W) Rhyolitic lava has a lower melting temperature than basaltic lava
X: X) Basaltic lava extrusion is typically explosive
Y: Y) Andesitic lava has intermediate silica content
Z: Z) Rhyolitic lava typically flows more slowly than basaltic lava
Answer: X) X) Basaltic lava extrusion is typically explosive
What is the term for a hydrocarbon containing one or more double or triple bonds?
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Identify all of the following three changes that would be expected as pure water is heated from 25 °C to 37 °C: 1) The H⁺ concentration increases; 2) The OH⁻ concentration decreases; 3) The density of the water decreases.
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Researchers at Brookhaven National Lab created an abiotic-biotic hybrid catalyst inspired by the reaction center in chlorophyll. While the researchers used cadmium selenide and zinc sulfide nanoparticles, what metal atom is used by nature in the reaction center in chlorophyll?
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Brookhaven National Lab scientists are developing catalysts to accelerate the breakdown of organophosphorus nerve agents. These agents typically function by interfering with the amount of what neurotransmitter?
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A position vector terminates at \((1,1)\) in the \(xy\)-plane and experiences a momentum described by the vector \(-\mathbf{i} + \mathbf{j}\). Toward what direction does the angular momentum vector point? W) Positive \(y\) X) Negative \(y\) Y) Positive \(z\) Z) Negative \(z\)
W: W) Positive \(y\)
X: X) Negative \(y\)
Y: Y) Positive \(z\)
Z: Z) Negative \(z\)
Answer: Y) Y) Positive \(z\)
A disk initially at rest undergoes an angular acceleration of three radians per second squared for a duration of six seconds. How many full rotations has the disk completed over this period?
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What is the sum of the largest prime number less than 70 and the smallest prime number greater than 70?
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What is the area of a triangle with sides of length 17, 14, and 11?
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In an operon, what is the name of the site upstream of a gene to which RNA polymerase binds in order to initiate transcription?
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Cdks are enzymes that play an important role in cell division. They act by adding what group to other protein substrates?
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What is the name for a saturated straight-chain alkane that contains six carbon atoms?
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The following incomplete compound name is missing its oxidation state for cobalt: di-amine-ethylene-di-amine-chloro-cobalt-sulfate. What is this oxidation number?
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What law, which is part of the mathematical formulation of Faraday’s law of induction, describes the direction of the EMF induced by a changing magnetic field?
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The position \(x\) of a rabbit running along a straight line as a function of time \(t\) is given by \(\displaystyle x(t)=t^3+2t^2-5t+6.\) What is the acceleration of the rabbit at \(t=2\)?
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In the proton–proton chain, hydrogen nuclei are converted to neutrons through interactions with what fundamental force?
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What type of variable star is most prevalent in globular clusters? W) Cepheid X) T Tauri Y) Mira Z) RR Lyrae
W: W) Cepheid
X: X) T Tauri
Y: Y) Mira
Z: Z) RR Lyrae
Answer: Z) Z) RR Lyrae
DOE researchers at the Lawrence Berkeley National Lab used the Advanced Light Source to perform X-ray diffraction to determine the chemical makeup of a mineral grain that was 10 microns in diameter. This mineral grain’s size is closest in size to which of the following? W) Single Clostridium tetani organism X) F-naught subunit of ATP synthase Y) Length of the largest human motoneuron Z) Nucleus of a human fibroblast
W: W) Single Clostridium tetani organism
X: X) F-naught subunit of ATP synthase
Y: Y) Length of the largest human motoneuron
Z: Z) Nucleus of a human fibroblast
Answer: Z) Z) Nucleus of a human fibroblast
Scientists at SLAC National Accelerator Lab are using cryo-electron microscopy to study viral particles. Cryo EM is a variation of what type of electron microscopy in which a beam of electrons passes through a specimen to form an image?
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In what cellular organelle are the receptors for lipid-soluble hormones typically located once they have bound their ligand?
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Identify all of the following three cellular junctions that allow direct passage of small molecules from the cytoplasm of one cell to another: 1) Gap junctions; 2) Adherens junctions; 3) Desmosomes.
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What is the absolute value of the complex conjugate of \(-5i\)?
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On a seven-by-seven grid of unit squares, how many squares of any size can be formed using only the line segments in the grid?
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What is the oxidation number for carbon in methanol?
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Identify all of the following three statements that accurately describe the work function of a metal: 1) It is the energy difference between the HOMO and the LUMO; 2) It is the valence energy level relative to vacuum; 3) It is the energy required to eject an electron.
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John places a block on a plank of wood, and slowly tilts the plank. When the plank reaches a 60° incline, the block begins to slide. To the nearest tenth, what is the coefficient of static friction between the block and the wood?
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The energy that it takes to eject an electron from the \(n=3\) state is how many times that to excite an electron from the ground state to the \(n=3\) state?
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What greenhouse gas is trapped in cage-like structures in ocean sediment and may be released to the atmosphere as ocean temperature increases?
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Two oceanic plates collide. All other factors being equal, which plate is more likely to subduct? W) The crust that is older X) The crust that is more felsic Y) The crust with higher average temperature Z) The crust with more arc volcanism
W: W) The crust that is older
X: X) The crust that is more felsic
Y: Y) The crust with higher average temperature
Z: Z) The crust with more arc volcanism
Answer: W) W) The crust that is older
C. elegans is a model organism notable for having a deterministic and exact development. To which phylum does it belong?
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Identify all of the following three classes of molecules that are intermediates in glycolysis: 1) 5-carbon molecules; 2) 4-carbon molecules; 3) 3-carbon molecules.
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What is the distance between the points \((0,7)\) and \((4,9)\)?
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Let \(f(x)\) be a function with continuous derivative, with \(f(3)=0\) and \(f'(3)=6\). Compute \[ \lim_{x\to 0}\frac{f(3+2x)+f(3-3x)}{x}. \]
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