Digital ACT Practice Questions

Researchers are investigating the effect of blue light intensity on the growth rate of a specific algae species, *Chlorella vulgaris*. They hypothesize that hig...

Scientists observed four exoplanets orbiting a distant star. The table below summarizes some of their characteristics: | Exoplanet | Orbital Period (Earth Days)...

An astrobiology team simulated planetary equilibrium temperature (T_eq in Kelvin) across four modeled terrestrial exoplanets with varying Bond albedos (A) and s...

Researchers investigated the catalytic reaction velocity (v) of an enzyme under varying substrate concentrations ([S]) and in the presence of two chemical inhib...

Three geochemists debate the primary trigger of the Cretaceous-Paleogene (K-Pg) boundary mass extinction 66 million years ago. Scientist 1 The extinction was ca...

**Study on Enzyme Catalase Kinetics** An aqueous solution of catalase was incubated with hydrogen peroxide (\( H_2O_2 \)) at various temperatures and pH levels....

A study investigates the effect of two different herbicides (Herbicide X and Herbicide Y) on the growth of a specific weed species (Weed Z) under varying soil p...

An environmental biology lab measured the dissolved oxygen concentration (DO in mg/L) in a freshwater reservoir at varying depths during midsummer: • Depth 1 m:...

Two biochemists debate the mechanism of enzyme inhibition for Enzyme X in the presence of Inhibitor Y: • Scientist 1 claims that Inhibitor Y is a competitive in...

In a physics experiment testing electromagnetic induction, a student rotates a planar copper coil of area $0.05\text{ m}^2$ inside a uniform magnetic field of $...

A planetary geology team analyzes core samples from three Martian craters (Crater X, Y, and Z) to determine relative age based on impact crater density and mine...

A chemistry student measures the pH of four aqueous solutions at $25^\circ\text{C}$: • Solution 1: $[\text{H}^+] = 1.0 \times 10^{-3}\text{ M}$ • Solution 2: $[...

An experimental assay measured the rate of DNA polymerase elongation at four different temperatures in the presence of $1.5\text{ mM }\text{Mg}^{2+}$: • $25^\ci...

A physics laboratory tested the radioactive decay of a sample of Isotope W. The initial activity was $1,600\text{ counts per minute (cpm)}$. After $36\text{ day...

Two astronomers debate the origin of Fast Radio Bursts (FRBs): • Astronomer 1 hypothesizes that FRBs originate exclusively from magnetars (highly magnetized neu...

An ideal gas sample in a sealed cylinder with a movable piston undergoes an isothermal expansion at a constant temperature of $300\text{ K}$. If the volume of t...

In a pea plant genetic cross between two heterozygous purple-flowered plants ($Pp \times Pp$), where purple flower allele ($P$) is dominant to white flower alle...

In a forensic DNA investigation, a molecular geneticist conducts Polymerase Chain Reaction (PCR) amplification on a short tandem repeat (STR) locus. The sample ...

In a ancient genomic paleontology lab, a molecular geneticist conducts Polymerase Chain Reaction (PCR) amplification on a Neanderthal mitochondrial fragment. Th...

In a viral epidemiology diagnostic clinic, a molecular geneticist conducts Polymerase Chain Reaction (PCR) amplification on a RNA-derived cDNA target sequence. ...

An astrophysicist measures the hydrogen absorption spectrum from Star Alpha. The rest laboratory wavelength for the designated spectral line is $\lambda_0 = 656...

A physical chemistry student investigated the vapor pressure of four organic liquids at $20^\circ\text{C}$: • Acetone: $24.6\text{ kPa}$, $\Delta H_{\text{vap}}...

An evolutionary biology experiment tracked allele frequencies in a population of fruit flies (*Drosophila melanogaster*) over 20 generations: • Generation 0: Al...

A student tested the electrical resistance of four copper wires of varying lengths and cross-sectional areas at $20^\circ\text{C}$: • Wire 1: Length $1.0\text{ ...