In biology, a spore is a component of sexual or asexual reproduction adjusted for dispersal and survival. Often for long periods, in negative conditions. Spores form a component of the life cycles of many plants, algae, fungi, and protozoa.
For example, bacterial spores are not part of a sexual cycle but are resilient structures used for survival in poor conditions. Spores are typically haploid sporophyte. Under favorable conditions, the spore can grow into a new organism using mitotic division. This division produces a multicellular gametophyte, which eventually makes gametes.
Two gametes come together to generate a zygote, which expands into a new sporophyte. This cycle is known as the alteration of generations. The spores of seed plants are created internally, and the megaspores and microspores are immersed in the formation of more complex structures.