Science
The Science subarea covers life, physical, and Earth/space science through the Massachusetts Science and Technology/Engineering Framework. Questions reward the scientific practices-models, investigations, data analysis, evidence-based explanation-as much as the facts.
Core concepts
- Life science: structure and function, life cycles, inheritance, and ecosystem interactions, including energy flow from producers to consumers.
- Physical science: matter and its properties, forces and motion, energy transfer, and simple waves.
- Earth/space: the water cycle, weather versus climate, Earth's surface processes, and patterns in the solar system.
- Scientific explanations use evidence and are revised when new evidence appears; a hypothesis is testable, not a guess.
Worked example
Cross two heterozygous pea plants (Bb × Bb), where B is dominant and b recessive. Reasoning: each parent can pass B or b, so the Punnett square gives BB, Bb, Bb, bb. Genotypes are 1 BB : 2 Bb : 1 bb. Because B is dominant, three of four offspring show the dominant phenotype; one shows the recessive phenotype. The 3:1 ratio is a prediction, not a guarantee for a small sample.
Traps that cost marks
- Saying energy is "lost" in a food chain; it is transferred and released as heat.
- Confusing weather (short-term) with climate (long-term).
- Treating a scientific theory as a guess.
- Confusing genotype with phenotype.