Transcript Types of Asexual Reproduction

Types of Asexual
Reproduction
3/17/2008
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Meiosis
Mitosis
Forms sex cells (sperm
and eggs)
Responsible for growth,
differentiation, and
asexual reproduction
½ the number of
chromosomes compared to
the parent cell
Genetically
identical to parent
cell
One replication and
two divisions
One replication and one
division
4 daughter cells
formed
2 daughter cells
formed
Asexual Reproduction
• Involves the process of mitosis
• Offspring are genetically identical to parent
Binary Fission
• Parent divides into 2 equal halves after
nucleus replicates
• No parent remains 2 daughter cells
grow to normal size
• Occurs in bacteria , protozoa , and
algae
Budding
• Parent organism divides into 2 unequal
halves
• Daughter cell forms from outgrowth or
bud off parent
• Buds may break off or remain attached
and form a colony
• Occurs in hydra and yeast
Sporulation (spore forming)
• Production of many spores in a special
spore producing structure ( spore case )
• Spores are microscopic , specialized cells,
containing nucleus and cytoplasm
within a hard case
• Occurs in molds , mushrooms , and
ferns
Regeneration
• Ability to grow back missing parts
• The more complex the organism, the
harder it is to regenerate
• Occurs in simple organisms such as
starfish and flat worm
Humans?
Vegetative Propagation
• piece of a body of a multicellular
organism gives rise to a new organism
• Common in plants - using stems,
leaves, or roots
• Can occur naturally or artificially
Natural Vegetative Propagation
• Bulb- Short underground stem with stored
food & fleshy leaves Ex. Onion, tulip
• Corm- Short underground stem with stored
food
Ex. Water chestnut
• Tuber- Enlarged underground stem
Ex. potato
• Runner- (stolon) horizontal stem with buds
along ground’s surface Ex. strawberry
• Rhizome- Underground horizontal stem
Ex. ginger
Tuber
Runner
Bulb
Rhizome
Corm
Artificial Vegetative Propagation
• Cutting- use part of plant to
reproduce (Ex. Spider plant)
• Layering- stem is bent over and covered with soil
 will root and form new plant (Ex. raspberry)
• Grafting- stem or bud of one plant is joined
permanently to another plant
(Ex. Seedless fruit tree )
scion
stock
Layering
Grafting