Transcript Asexual Reproduction

Asexual Reproduction
Bacteria, Protists, Fungi, and
Animals
What is asexual reproduction?
The formation of a new individual that
has identical genetic information to its
parent
 Mitosis and cell division are the basis for
the asexual reproduction of many
organisms

Bacteria
Bacteria are unicellular organisms that
do not contain a true nucleus.
 Organisms that do not have a nucleus
are called prokaryotes
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Asexual Reproduction
of Bacteria
Bacteria reproduce asexually through a
process called binary fission
 Binary fission: a parent cell divides so
that each new cell contains a single
chromosome carrying a complete set of
DNA identical to that of the parent

Asexual reproduction
in Protists
Protists are unicellular and contains a
nucleus
 If they contain a nucleus, what process
do you think they require to reproduce
asexually?
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Asexual Reproduction
in Fungi
Some types of fungi are mould, yeast
and mushrooms.
 They are composed of many thin
filaments called hyphae which grow over
the surface of and into the bodies of
other organisms to obtain food.
 Fungi reproduce asexually through
fragmentation, budding, and spores
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Fragmentation
Fragmentation: a small piece of fragment
breaks away from the main mass hyphae
and grows into a new individual.
 What must the fragment contain in order
to develop into a new organism identical
to its parent?
 What is yeast?

Yeast
Yeast is a unicellular fungi often used to
make bread or alcohol products.
 Yeast reproduce asexually by budding
 Budding: First, a copy of the nucleus is
made. A tiny bud begins to form on the
cell wall. This bud contains the new
nucleus and continues to grow very
large. It eventually breaks away to
become a single cell.

Mould
In order for mould to reproduce
asexually, they have to reproduce spores
 Spore: is a reproductive cell that can
grow into a new individual through
mitotic cell division.
 They are stored in a case called a
sporangium.

Asexual Reproduction in Animals
Animals are classified as vertebrates and
invertebrates
 Invertebrates can reproduce asexually to
form one or more identical offspring from
a single parent.
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Animals
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Planaria are a type of flatworm that reproduce
asexually by dividing into two and regenerating
the missing parts.
 Sponges and hydras reproduce asexually by
budding.
 A cell, usually near the base of the organism
undergoes mitosis and cell division to produce
a new cell or a bud.
 When the bud has completed its development,
it will separate.
Asexual Reproduction in Plants
Plants reproduce asexually by mitotic
cell division where each new plant will
have the same DNA as its parent.
 What is the difference between the
growth of animals and plants?
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The Basis of Asexual Reproduction
in Plants
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Plants continue to grow throughout their lives
The tips of their roots and stems contain
growing areas called meristem.
 Meristem is made up of unspecialized cells
that undergo mitosis and cell division
repeatedly, producing new cells.
 A way of spreading plants is by cutting lengths
of parent stems to make exact copies
 This is called cloning, the process by which
identical offspring are produced from a single
cell or tissue.
New Plants from roots
Meristem cells divide mitotically to
produce stems, leaves and other roots.
 Why is it so hard to get rid of
dandelions?
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New plants from Stems
In some plants, meristematic cells in the
stem can divide to produce cells that will
become a new plant.
 Strawberries have special stems called
runners and they grow from the tips of
these cells

Layering: a technique which uses the
ability of some plants to reproduce more
easily from stems than from other plants.
 A branch of the parent plant is bent down
to the ground and covered in soil.
 Roots will grow from the buried stem and
the exposed tip will begin to grow.
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Grafting: a technique used to asexually
reproduce stems of plants.
 Stems from plants are attached or
grafted to the stock of related or similar
plants.
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Tissue Culture
Tissue culture is a technique used to
make identical plants grow quickly and
economically.
 They take specialized cells from the
plant and grow them in a special solution
in the laboratory.
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