Transcript Asexual/Sexual Reproduction

Reproduction
Asexual Reproduction
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Process by which a single parent
reproduces by itself.
Methods of Asexual Reproduction
Binary fission
 Fragmentation
 Regeneration
 Budding
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Binary Fission
Separation of a single cell into two
identical daughter cells.
 Used by most bacteria.
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Fragmentation
The parent breaks into different fragments
which eventually form new individuals.
 Used by flatworms.
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Regeneration
When an animal loses a body part and it
can grow a replacement.
 Used by echinoderms.
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Budding
An offspring grows out of the body of the
parent.
 Used in hydra.
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Sexual Reproduction

Process by which two cells from two
different parents unite to produce the first
cell of a new organism.
Methods of Sexual Reproduction
Fertilization
 Pollination
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Fertilization
The union of male and female gametes to
form a zygote.
 Used by humans.
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Pollination
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Fertilization in flowering plants.
Asexual vs. Sexual Reproduction
Asexual
Sexual
one parent
two parents
Usually in single-celled organisms
Usually in plants, animals, and
other multi-cellular organisms
Uses mitosis to reproduce cells
Uses meiosis to reproduce
Includes binary fission, bacterial
conjugation, fragmentation,
budding, and regeneration
Includes fertilization and
pollination.
Cell Growth
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In most cases, living things grow by producing more
cells.
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There are reasons that cells divide rather than growing
themselves.
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On average, the cells of an adult are no larger than those of a
child, there are just more of them.
The larger a cell becomes, the more demands the cell places on
its DNA
The larger cell has more trouble moving enough nutrients and
wastes across the cell membrane.
The ratio of surface area to volume must remain high.
Before it becomes too large, a growing cell divides
forming two “daughter” cells in a process called cell
division.
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DNA is replicated so that each daughter cell has its own copy