Transcript Reproduction - Powell County Schools

REPRODUCTION
Sexual and Asexual
Reproduction
Reproduction – the process of living things producing the
same type of living thing.
Examples – horses produce horses, humans produce
humans, and tomato plants produce tomatoes.
* Like produces like.
There are two types of reproduction: asexual and sexual
Asexual Reproduction
Living things that reproduce from only one parent.
Examples: Regeneration, budding, and cellular division.
Advantages of Asexual Reproduction:
• animals that live in one place & unable to look for
mates reproduce asexually.
• numerous offspring can be produced without a
great amount of energy or time.
• One single organism can start new colonies in
new locations.
• Mating partners are not needed to be found.
• More reliable (less to go wrong in cell division)
Disadvantages of Asexual Reproduction:
• Species may not be able to adapt to a changing
environment
Regeneration
Regeneration
(before)
Regeneration
(after)
Crown of Thorns Story
Regeneration
(ex. starfish)
Can humans regenerate body parts by
asexual reproduction?
Regeneration
(ex. Planaria)
Budding
(ex: Hydra)
Cellular Division
(also called Binary Fission)
• Protozoa
Binary Fission
(ex. paramecium)
Binary Fission
(ex. bacteria)
Asexual Reproduction in Plants
• Propagation-transplanting parts of a plant to a
new growing area (ex. Rhizomes, runners, bulb
formation, rooting from stems)
• Budding-tiny bud growing off parent plant (ex.
Potato “eyes”, branches budding)
• Spores-reproductive cells that produce a new
organism (ex. Ferns, mushrooms, molds)
Propagation
Plant Budding
Spores
Sexual Reproduction
Sexual reproduction
usually requires two
parents (partners).
Examples: frogs,
deer, bats, humans,
and flowers.
Surinam Toad
• http://www.youtube.com/watch?v=mZ7b4spjXhw
Advantages of Sexual Reproduction:
• The offspring will be different than its parents. This allows
the species to adapt to its surroundings.
Galapagos Finches
• http://www.youtube.com/watch?v=l25MBq8T77w
Disadvantages of Sexual Reproduction:
• Often slower than asexual reproduction, and less reliable
(more mutations, problems)
• Much energy is used in mating processes
•
http://videos.howstuffworks.com/animal-planet/28366-fooled-by-nature-bowerbirds-seduction-video.htm
• Can’t always find suitable mate
TWO TYPES OF
REPRODUCTION
• 1. Internal Fertilization
• 2. External Fertilization
Internal Fertilization
• Conjugation-
Sexual reproduction
between microscopic
organisms
Asexual
budding
External Fertilization
• Sex cells are dispersed
out of the body in water
• Examples: fish,
salamanders,
jellyfish
Meiosis
• Produces sex cells only (sperm or egg cells)
• Takes place in the reproductive organs of organisms that
reproduce sexually.