Physical Education is not a core subject in secondary school curriculum, although it is often offered as an elective.

Geometry is the branch of Mathematics that deals with the study of shapes and their properties.

Nuclear fission is a type of nuclear reaction, not a type of chemical reaction.

Analysis is not a part of the scientific method, although it is often used to interpret the results of an experiment.

Biography is a type of non-fiction writing, not a type of literary genre.

The Declaration of Independence is not a part of the United States Constitution.

Theocracy is a type of government in which religious leaders hold political power, not a type of government in which a small group of people hold political power.

Barter economy is not a type of economic system, although it is a way of exchanging goods and services without using money.

Sound energy is not a type of energy, although it is a type of wave.

Bacterial cell is not a type of cell, although it is a type of prokaryotic cell.

Vascular tissue is not a type of tissue, although it is a type of plant tissue.

Endocrine system is not a type of organ system, although it is a type of system in the body.

Virus is not a type of organism, although it is a type of infectious agent.

Ocean is not a type of ecosystem, although it is a type of biome.

Light pollution is not a type of pollution, although it is a type of environmental problem.