Science Hub: Earth Science, Biology, Chemistry and Physics

The United States Army provides this FREE online science hub features practice test questions and lessons on science subjects covered in high school – Earth Science, Biology, Chemistry and Physics. The material is grouped by subject area and provides a detailed explanation for each answer. Biology lessons and question banks include material on cellular structure and processes, structure of DNA and replication, DNA translation and mutation, taxonomy, and living systems. Physics lessons and question banks include material on Newton’s law and mechanical efficiency, wave phenomena, the movement of heat energy, impact of energy sources, and calculation questions. Chemistry lessons and question banks include material on fluids, the periodic table, physical and chemical changes in matter, conservation of mass and energy, and solution chemistry. Earth Science lessons and question banks include material on bacteria and viruses, evolution and natural selection, matter and energy cycles, interactions in an ecosystem, and plants.