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asexual reproduction notes

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Reproduction is a marvelous culmination of individual transcendence. Individual organisms come
and go, but, to a certain extent, organisms "transcend" time by reproducing offspring. Let's take a
look at reproduction in animals.
What Is Reproduction?
In a nutshell, reproduction is the creation of a new individual or individuals from previously
existing individuals. In animals, this can occur in two primary ways: through asexual reproduction
and through sexual reproduction. Let's look at asexual reproduction.
Asexual Reproduction
In asexual reproduction, one individual produces offspring that are genetically identical to itself.
These offspring are produced by mitosis. There are many invertebrates, including sea stars and sea
anemones for example, that produce by asexual reproduction. Common forms of asexual
reproduction include:
In this form of asexual reproduction, an offspring grows out of the body of the parent.
Hydras exhibit this type of reproduction.
Gemmules (Internal Buds)
In this form of asexual reproduction, a parent releases a specialized mass of cells that can
develop into offspring.
Sponges exhibit this type of reproduction.
In this type of reproduction, the body of the parent breaks into distinct pieces, each of
which can produce an offspring.
Planarians exhibit this type of reproduction.
In regeneration, if a piece of a parent is detached, it can grow and develop into a
completely new individual.
Echinoderms exhibit this type of reproduction.
This type of reproduction involves the development of an egg that has not been fertilized
into an individual.
Animals like most kinds of wasps, bees, and ants that have no sex chromosomes
reproduce by this process. Some reptiles and fish are also capable of reproducing in this
Advantages and Disadvantages of Asexual Reproduction
Asexual reproduction can be very advantageous to certain animals. Animals that remain in one
particular place and are unable to look for mates would need to reproduce asexually. Another
advantage of asexual reproduction is that numerous offspring can be produced without "costing"
the parent a great amount of energy or time. Environments that are stable and experience very
little change are the best places for organisms that reproduce asexually. A disadvantage of this
type of reproduction is the lack of genetic variation. All of the organisms are genetically identical
and therefore share the same weaknesses. If the stable environment changes, the consequences
could be deadly to all of the individuals.
Asexual Reproduction in Other Organisms
Animals are not the only organisms that reproduce asexually. Yeasts, plants and bacteria are
capable of asexual reproduction as well. Bacterial asexual reproduction most commonly occurs by
a kind of cell division called binary fission. Since the cells produced through this type of
reproduction are identical, they are all susceptible to the same types of antibiotics.