A doctrine that the genesis or production of living organisms can take place only through the agency of living germs or parents; -- called also biogeny; -- opposed to abiogenesis.

the production of a chemical compound by a living organism.

The theory that living systems arise only from pre-existent living systems.

the production of living organisms from other living organisms

The theory that living things come from other living things.

the concept that all life arises from living matter

The principle that a living organism can only arise from other living organisms similar to itself and can never originate from non-living material.