Reproduction in Plants Flashcards
asexual reproduction
a process resulting in the production of genetically
identical offspring from one parent
sexual reproduction
a process involving the fusion of the nuclei of two gametes to form a zygote and the production of offspring that are genetically different from each other
fertilisation
the fusion of the nuclei of gametes. fertilisation occurs when a pollen nucleus fuses with a nucleus in an ovule
pollination
transfer of pollen grains from an anther to a stigma
self-pollination
the transfer of pollen grains from the anther of a flower to the stigma of the same flower or a different flower on the same plant
cross-pollination
the transfer of pollen grains from the anther of a flower to the stigma of a flower on a different plant of the same species
advantages of asexual reproduction for species
- only one parent is required
- faster than sexual reproduction
- fusion of gametes is not required
- beneficial qualities are passed to the offspring
advantages of asexual reproduction for plants
- can rapidly colonize the area
- artificial vegetative propagative can occur, which is faster
advantages of asexual reproduction for plants
- can rapidly colonize the area
- artificial vegetative propagative can occur, which is faster
disadvantages of asexual reproduction for plants
- if they rapidly colonize, then overcrowding will occur
- no genetic variation, can wipe out the whole population
disadvantages of asexual reproduction for species
- no genetic variation, so less well adapted
advantages of sexual reproduction in plants
- higher yield of crop
- grow and mature faster
- resistant to diseases
- resistance to unfavourable environmental conditions
advantages of sexual reproduction in plants
- higher yield of crop
- grow and mature faster
- resistant to diseases
- resistance to unfavourable environmental conditions
disadvantages of sexual reproduction in plants
- wastage of pollen and energy
- slower than asexual
- may be less well adapted
advantages of sexual reproduction in species
- genetic variation, better well adapted
- inherit beneficial qualities from both the parents
disadvantages of sexual reproduction in species
- two parents are required
- slower
- fusion of gametes is required
disadvantages of sexual reproduction in species
- two parents are required
- slower
- fusion of gametes is required
function of petals, sepals and flower stalk
petal: brightly coloured to attract insects, provide a platform for insects to land, have lines that guide insects to obtain nectar
sepal: protect other parts of the flower during the bud stage
flower stalk: attaches flower to the stem
function of stamen
anther: contains pollen grains and vascular bundle
filament: holds anther in a suitable position to disperse the pollen
pollen grain: contain male gametes
function of carpel
stigma: receives pollen grains, secretes a sugary fluid that stimulates pollen grains to germinate
style: holds the stigma
ovary: contains ovule - female gamete
advantages and disadvantages of self-pollination
advantages:
- one parent required
- less wastage of pollen and energy
- doesnt depend on external factors
disadvantages:
- less genetic variation
- offspring may be weaker, smaller, less resistant
- high chance of harmful recessive alleles being expressed
advantages and disadvantages of cross-pollination
advantages:
- more viable seeds produced
- greater genetic variation
- inherit qualities from both parents
disadvantages:
- two parents required
- depends on external factors
- more wastage of energy and pollen
