Asexual Reproduction

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Transcript Asexual Reproduction

How do organisms reproduce?
1) Who thinks they can define Reproduction?
The process by which living things produce other
living things like themselves.
The production of offspring.
2) What are Chromosomes?
Found in Nucleus
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cell
Structures found in the nucleus of our cells that determine our
physical characteristics (traits). They have the genetic information
(DNA).
Chromosomes need to be passed
onto the offspring. They are the
“instructions” for the cell.
3) Types of Reproduction:
Asexual Reproduction
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Parent
Clones
Offspring
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Clones
Genetic Information
(Chromosomes)
Characteristics of Asexual Reproduction:
1) Is the creation of a new individual from only 1 parent.
2) Genetic information of offspring is identical to the parent.
Do the cells in our body undergo asexual
reproduction?
Yes
4) When do the cells of our body undergo
Asexual Reproduction?
Growth
Repair
Types of Asexual Reproduction:
(Mitosis)
BINARY FISSION
Two equal sized offspring
Example: Bacteria & Ameoba
Dividing Bacteria
less than one minute
http://virtuallaboratory.colorado.edu/Biofundamentals/lectur
eNotes/Topic5-1_CellDivision.htm
Budding (Unicellular)
• Cytoplasm divides unequally (Parent large
and offspring small)
• Example: yeast (unicellular)
Budding (Multicellular)
• Outgrowth from the body of
parent that develops into a
complete organism
• May detach: hydra
(multicellular)
• May remain attached:
colony of coral
Fragmentation and Regeneration
• Development of lost parts or growth of an entire
new organism from part of original organism
• Examples: Sea Star and Planaria
Planaria Regeneration
2 minute video
http://www.youtube.com/watch?v=vXN_5SPBPtM
Sporulation
• Specialized cells are
released by parents
• Enclosed in protective
capsules
• Develop into a new
individual when
environmental conditions
are favorable
• Example: bread mold
Vegetative Propagation
Roots, stems, & leaves are called
vegetative structures.
They normally play a role in the
nutrition & growth of plants.
When they give rise to a new
plant, the process is called
vegetative propagation.
Types of Vegetative Propagation:
Natural:
1)Runners
2)Bulbs
3)Tubers
4)Rhizomes
Artificial:
1)Cuttings
2)Grafting
Runners
• Sideways stem that has buds
above Ground
• Example: Strawberries
Bulbs
• Underground stem with fleshy
leaves which store food
• Example: Tulip
Tuber
• Underground stem enlarged for
storage of food
• Example: Potatoes
Rhizomes
• Stems that grow sideways underground. New plant
can grow from these stems.
• Example: Ferns
Artificial Vegetative Propagation
Done by humans
Why?
• Asexual reproduction
• offspring are
genetically identical
• keep traits that you like
• Fast
• Seedless!
Cuttings
Vegetative part of a plant is
cut, and it can develop into
a new plant.
Root Growth
Grafting
A cutting from one plant (scion) is attached to
The main body of a rooted plant (stock).
Example: Apples
Apple Tree Grafting
4 minute video
http://www.youtube.com/watch?v=LTqG8-OhElY
ASEXUAL REPRODUCTION
• No sex cells
• No sex organs – no
ovaries or testes
• Mitosis used
• Offspring are clones
• No variation
Brain Pop: Asexual Reproduction
3 minute video
https://www.brainpop.com/science/cellularlifeandgenetics/as
exualreproduction/
6) What is Sexual Reproduction?
It involves the joining of two cells to begin the
development of a new individual.
These special cells are called: Sex Cells (Gametes)
7) What are the names of these sex cells?
Egg cell
(Female)
Sperm Cell
(Male)
8) The joining of a sperm cell with
an egg cell is called fertilization.
Sexual Reproduction
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Egg
Sperm
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Offspring
A fertilized egg cell is called a Zygote
Characteristics of Sexual Reproduction:
1) Is the creation of a new individual from 2 parents.
2) Offspring are not genetically identical to the parents.
We get half our genetic information
from mom and half our genetic
information from dad
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Males:
Sperm cells
Females:
Egg cells
9) Asexual vs.
Sexual Reproduction
1 Parent
Offspring are
identical
Produce
Offspring
Critical for survival
of the species
Bacteria, Amoeba,
Body Cells
Asexual Reproduction
2 Parents
Offspring are
not identical
Humans,
Dogs, Plants
Sexual Reproduction