Reproduction is the creation of one thing as a copy of, product of, or replacement for a similar thing, e.g. photocopying and the making of replicas.
It is perhaps most commonly used in the context of biological reproduction and sex:
Sexual reproduction is a biological process by which organisms create descendants through the combination of genetic material. These organisms have two different adult sexes, male and female.
Asexual reproduction is a biological process by which an organism creates a genetically similar copy of itself without the combination of genetic material with another individual. For example, the Hydra (invertebrates of the orderHydroidea) and yeast are able to reproduce by budding. These organisms do not have different sexes, and they are capable of "splitting" themselves into two or more parts and regrow their body parts. Some 'asexual' species, like hydra and jellyfish, may also sexually reproduce. Most plants are capable of vegetative reproduction. Other ways of asexual reproduction are binary fission, fragmentation and spore formation.
There are a wide range of reproductive strategies employed by different species.
Some animals, like the human (sexually mature after adolescence) and Northern Gannet (5-6 years), produce few offspring. Others reproduce quickly, but unless raised in an artificial environment, most offspring do not survive to adults. A rabbit (mature after 8 months) produces 10 - 30 offspring per year, a Nile Crocodile (15 years) produces 50, and a fruit fly (10-14 days) produces up to 900. Both strategies can be favoured by evolution: animals with few offspring can spend time nurturing and protecting them, hence greatly decreasing the need to reproduce; on the other hand, animals with many offspring do not need to spend parental energy on nurturing, allowing more energy to be devoted to survival and more breeding.
These two strategies are known as K-selection (few offspring) and r-selection (many offspring). Which strategy is favoured depends on a wide range of circumstances.
Reproduction is one of the essential functions of plants, animals, and single celledorganisms, as necessary for the preservation of the species as eating is for the preservation of the individual.
The typical malereproductivecell, which is known as a sperm, spermatozoon, or spermatozoan, is a motile cell with a head containing the nucleus and a whiplike tail with which it swims.
Plant reproductivecells are roughly similar to animalcells, the malecell being known as the sperm or microgamete and the femalecell as the ovum or macrogamete.
Natural vegetative reproduction is mostly a process of herbaceous and woody perennials, and typically involves structural modifications of the stem, although any horizontal, underground part of a plant (whether stem or a root) can contribute to vegetative reproduction of a plant.
A rhizome is a modified stem serving as an organ of vegetative reproduction.
Man-made methods of vegetative reproduction are usually enhancements of natural processes, but range from simple cloning such as rooting of cuttings to artificial propagation by laboratory tissue cloning.
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