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Praxis Fundamental Subjects study materials
Praxis Fundamental Subjects study resources

Praxis Fundamental Subjects: Science

Praxis Fundamental Subjects · Work through your exam, one topic at a time.

All guide sections

Science

This domain samples life science, physical science, Earth and space science, and scientific inquiry. Items ask you to classify organisms and processes, predict outcomes of physical changes, interpret data tables, and identify the design of a fair investigation.

Life science

Cells are the basic unit of life; plant cells have cell walls and chloroplasts, animal cells do not. Photosynthesis uses carbon dioxide, water, and light energy to make glucose and release oxygen; cellular respiration reverses the equation to release energy. Energy flows through a food chain from producers to consumers, and roughly 90% is lost as heat at each level, so top predators are fewest. Inherited traits come from genes; learned behaviors come from environment.

Physical science

  • States of matter change with energy added or removed: melting, freezing, evaporation, condensation, sublimation.
  • Density = mass ÷ volume; an object denser than water sinks.
  • Newton's laws: inertia; force = mass × acceleration; equal and opposite action–reaction pairs on different objects.
  • Energy forms transfer but are conserved; light and sound travel as waves.

Earth and space

Rocks are igneous (cooled magma), sedimentary (compacted layers), or metamorphic (heat and pressure). The water cycle moves water through evaporation, condensation, precipitation, and collection. Earth's rotation causes day and night; its revolution and axial tilt cause seasons. Weathering breaks rock down, erosion transports the pieces, deposition drops them.

Worked example

A block has a mass of 20 g and a volume of 8 cm³. Density = 20 ÷ 8 = 2.5 g/cm³. Because 2.5 exceeds water's 1.0 g/cm³, the block sinks. Dividing volume by mass instead inverts the ratio and gives a false value.

Traps that cost marks

Confusing mass with weight, rotation with revolution, weather with climate, and weathering with erosion; calling a well-supported explanation a “theory” in the everyday sense rather than a broad, repeatedly tested explanation; and mistaking a controlled variable for the control group.