16 Reproduction in Plants Flashcards
Asexual reproduction
a process resulting in the production of genetically identical offsprings from one parent
Advantages of asexual reproduction
- Faster
- More energy efficient
- Only requires one parent
Disadvantages of asexual reproduction
- Low genetic variation
- Rapid spread of disease
- Increased competition
Sexual reproduction
a process involving the fusion of the nuclei of two gametes to form a zygote and the production of genetically different offsprings
Advantages of sexual reproduction
- Genetic variation in offsprings
- Species can adapt to environmental changes as genetic variation gives them a selective advantage by natural selection
- Disease less likely to affect an entire population due to genetic variation
Disadvantages of sexual reproduction
- Requires two parents hence more time and energy is used to find mates
- Offspring might have unfavourable characteristics
Female parts of a flower
Carpel:
1. Stigma
2. Style
3. Ovary
4. Ovule
Male parts of a flower
Stamen:
1. Anther
2. Filament
Advantages of self pollination
- Maintains parental characteristics
- Does not depend on pollinators
Disadvantages of self pollination
- Lack of variation leads to weaker offsprings
Advantages of cross pollination
Wider variation leads to healthier offsprings
Disadvantages of cross pollination
- Wasted pollen grains
- Undesirable traits might be introduced
- Heavily dependent on pollinators
Fertilisation
when a pollen nucleus fuses with an ovule nucleus
How fertilisation occurs in plants?
- Pollen grains grows a tube down through the style and ovary. It secrets enzymes to digest a pathway through the style
- Pollen tube grows through the micropyle into the ovule
- Pollen nucleus travels along the pollen tube into the ovule where it fuses with the ovule nucleus
