Chapter 42- Flower Structure Flashcards
what is the calyx of a flower
region consisting of flattened sepals (green leaves)
what is the corolla of a flower
region made of petals
what is the androecium
collective term for stamens
-stamen consists of filament and an anther
what is the gynoecium
collective term for carpels
what does the carpel consist of
ovary, style, and stigma
- ovules produced in ovary
- one ovum produced per ovule
how does pollen form
anthers contain 4 microsporangia which produce microspore mother cells (2N)
- 2N microspore mother cells produce 1N microspores through meiosis
- 1N microspore develops by mitosis into 1N pollen
how many megaspores does the mother cell ovule produce
4 1N megaspores after meiosis
how many mitotic divisions does the surviving megaspore produce
8 haploid nuclei from mitotic divisions
what is self pollination
pollen from a flower’s anther pollinates stigma of the same flower
how have flowers evolved with pollinators
they have coevolved to help successfully attract pollinators to their flowers
what are 3 evolutions of flowers to attract pollinators
color changes fro bees
- landing platforms for butterflies
- large amounts of nectar for birds
what are 2 advantages of self fertilization
favorable in stable environments
offspring are more uniform and probably better adapted to their current environment
What are dioecious plants
produce only ovules or pollen, promotes cross pollination
what are monoecious plants
produce male and female flowers on the same plant
what is self incompatibility
when flowers prevent themselves from self fertilizing (mono and dioecious plants)
