There are two types of populations: unitary populations and modular populations. In unitary populations, each individual develops from a single zygote through sexual reproduction. However, many plant and invertebrate species can also reproduce asexually through vegetative propagation, budding off new individuals from the parent plant or animal. These asexually produced individuals are called ramets, and a group of ramets derived from the same original zygote is considered a clone.

1. Unitary population
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2. chap.17 metapopulations 2
There are two types of populations:
• a) Unitary Populations.
• b) Modular Populations.
• In unitary populations, each individual is derived
from zygote (the product of fertilization of male
and female gamete) and the growth of such
individuals is determinate and predictable.

3. In unitary organisms (most animals) there is
usually no problem recognizing individuals,
because they are both genetically and
physiologically separate.
Many species of plants and invertebrates,
however, have vegetative propagation to
produce new individuals, besides sexual
reproduction.
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5. • Plants derived from one zygote can produce new plants or
modules a sexually by means of buds on hallow horizontal
roots or by stems that touch the ground.
•
• Individual plants produced by sexual reproduction are genets.
• Asexually produced individuals derived from the generic
parent are called gamets.
• A group of gamets originating from the same genet makes a
clone.
• Gamets may remain linked to the parent or exist individually.
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6. • Examples:
• a) Plants as grass clumps, blackberries, strawberries, that
reproduce asexually by
• runners or stolons. Often never clear whether its a single
modular organism or a
• ramet
• b) Animals such as corals, hydroids, byrozoans, and
tunicates that reproduce asexually
• by budding. Many primitive metazoans are loosely
organized and form modular
• colonies.
• c) Fungal mycelia are in the same category, Each hypha is
potentially an organism, but
• the mycelium as a genet can be enormous in size.
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7. • All gamets are derived from the same zygote
and may be considered as one individual or
genet.
• For practical reasons, in plant population
studies individual gamets are counted as and
function as individual members of the
population.
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