What is the informal term used to describe theories about the origins of life?

The informal term used to describe theories about the origins of life is known as abiogenesis. This term refers to the process by which life arose naturally from non-living matter, a fundamental concept in the study of the origins of life on Earth. Abiogenesis encompasses various scientific theories that explore how life may have originated from simple organic compounds, leading to the complex biochemistry seen today.

The other terms listed have distinct meanings that are not directly related to the origins of life. Biogenesis refers to the principle that life arises from pre-existing life, rather than from non-living materials. Evolution pertains to the process by which species change over time through mechanisms such as natural selection, and photosynthesis is a process used by plants and some microorganisms to convert light energy into chemical energy, specifically to produce food from carbon dioxide and water. These concepts are essential in their respective fields but do not focus on how life originally came into existence from non-living components.