Asexual reproduction

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Asexual Reproduction is reproduction without sex.

In this form of reproduction, a single organism or cell makes a copy of itself. The genes of the original and its copy will be the same, except for rare mutations. They are clones.

The main process of asexual reproduction is mitosis. This type of reproduction is common among some single-cell organisms, for example, Amoeba, Paramecium. Many plants also reproduce asexually.

Types of asexual reproduction[change | change source]

Binary fission[change | change source]

A cell splitting and becoming two cells (overview)

Some organisms like bacteria reproduce using binary fission. They split in two, so one bacterium becomes two bacteria. This always leads to daughter cells, and the offspring will be identical to the parent.

Budding[change | change source]

Some plants reproduce by asexual budding; small complete plants grow along the edge of this leaf.

Budding is similar to binary fission, but it is used by plants and some animals, which cannot simply split in half as bacteria can. It is when a small part of a plant or animal breaks off and then, while they are separated from their "mother", they start to grow until both the "parent" and the "offspring" are the same size and both are capable of budding again. This may happen many more times.

Parthenogenesis[change | change source]

Parthenogenesis is found in both plants and animals. Eggs develop without fertilisation. Examples occur in water fleas, rotifers, aphids, stick insects, some ants, bees and parasitic wasps. Parthenogenesis is very rare for vertebrates.[1]

Vegetative propagation[change | change source]

Very common in some types of plants using rhizomes or stolons (for example in strawberry). Other plants form bulbs or tubers (for example tulip bulbs and dahlia tubers). Some plants may form a clonal colony, where all the individuals are clones, and the clones may cover a large area.

Spores[change | change source]

Asexual reproduction in Ascomycota is by the formation of conidia, a type of spore. Here is a chain of four conidia of Alternaria

Fungi (for example, mushrooms) produce spores, which may be asexual or sexual. The asexual spores have the genetic material inside, which allows them to make a whole new organism identical to its parent. They are produced by mitosis. Different fungi make different kinds of asexual spores, conidia, oidia, and pycniospores. The shape and colour of the spores can be helpful to identify the species of fungus.

Sexual vs asexual reproduction[change | change source]

Type Advantages Disadvantages
Asexual reproduction No mate needed. Many offspring produced quickly No variation in the offspring.
Sexual reproduction Genetic variation in the offspring. Requires both sexes to participate.

References[change | change source]

  1. Engl, New; Aquarium. "Two Baby Anaconda Born in All-Female Adult Exhibit". New England Aquarium. Retrieved 2019-06-01.

Other websites[change | change source]