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Reproduction is the creation of one thing as a copy of, product of, or replacement for a similar thing, e.g.
photocopying.
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 order Hydroidea)
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, will also be able to perform sexual reproductions. Most plants are capable of vegetative reproduction.
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 offsprings 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.
Edited By Brandon Almas, Grade 9 Student.
Defination: a single organism gives rise to offspring with identicle genetic infromation (eg.) paramecium, amoebae, human skin
cells, and bacteria.
There are five ways to reproduce asexually:
Binary Fission,
Fragmentation,
Spore Formation,
Budding,
Vegatative Reproduction.
See also
External links
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