Reproduction
Asexual vs. Sexual
Section 2.2 p. 30-36
What is Reproduction, Why Reproduce
The production of offspring by a sexual or asexual process.
So essentially the action or process of making a copy of something.
So We reproduce to ensure our Survival
2 Main Types of Reproduction
• Asexual
• Only one parent
• The offspring are identical
• Faster and easier method
• Usually produces large
number of offspring
Sexual Reproduction
-Reproduction involving two
parents
-New individual at least slightly
different from either parent
-Guarantees greater variety
amongst members of the species
Asexual Reproduction Methods
• Binary Fission: Cell splits exactly in two, producing two identical cells
• Budding: Parent produces a small bud that eventually separates and
becomes a new individual identical to the parent
• Spore Reproduction: Produced by division of cells on the parent
• Vegetative Reproduction: is the reproduction of a plant that does not
involve a seed
• i.e. Cuttings, Runners, Tubers, Bulbs, Shoots and Suckers
Parthenogenesis
Unfertilized eggs of female develop into new
organism without being fertilized.
eg. Mexican whiptail lizard
•An asexual form of reproduction found in
females where growth and development of
embryos or seeds occurs without fertilization by
a male. The offspring produced by
parthenogenesis almost always are female in
species where the XY chromosome system
determines sex
Other Types of Asexual Reproduction
• Hermaphroditism
• Is the capacity to produce both eggs and sperm
• Is an adaptation to a solitary life style
Serial Hermaphrodites
• May change sex in response to environmental cues including social
interactions
• i.e. Some female coral reef fish may transform into males if the dominant
male is removed. Testosterone is no longer metabolized into estrogen so the
female undergoes a sex change