Development Of Organisms And Continuity Of Life: sexual And Sexual Reproduction
16.2 Asexual And Sexual Reproduction
Asexual Reproduction
- Definition: One parent produces offspring genetically identical to itself (clones).
- Process: By mitosis.
- Examples:
- Bacteria (binary fission).
- Potato tubers.
- Hydra (budding).
Advantages
- Rapid population growth.
- Only one parent needed.
- Offspring inherit successful traits.
Disadvantages
- No genetic variation.
- Susceptible to disease and environmental changes.
Written And Compiled By Sir Hunain Zia, World Record Holder With 154 Total A Grades, 7 Distinctions And 11 World Records For Educate A Change O Level And IGCSE Biology Full Scale Course
Sexual Reproduction
- Definition: Involves fusion of haploid gametes → diploid zygote.
- Process: By meiosis (produces gametes) + fertilisation.
- Offspring: Genetically different from parents.
Advantages
- Genetic variation.
- Better chance of survival in changing environment.
- Enables natural selection.
Disadvantages
- Slower process.
- Requires two parents (or pollinators).
Key Point
- Asexual → fast, no variation.
- Sexual → slower, produces variation.
Written And Compiled By Sir Hunain Zia, World Record Holder With 154 Total A Grades, 7 Distinctions And 11 World Records For Educate A Change O Level And IGCSE Biology Full Scale Course