Flower Lab Flashcards
flowers are a modified form or which organ?
leaves
how are wind-pollinated flowers modified?
large floppy stamens with feathery stigma, usually not much resource goes into sepals or flowers
how are animal-pollinated flowers modified?
attraction to animals, such as nectar glands, large receptacles for landing, sturdy tubular structures for hummingbird beaks
what are the four basic flower parts?
- sepals
- petals
- pistil
- stamens
what is the function of the sepals?
typically Ps and protection of delicate petals
what is the function of the petals?
provide landing and attraction to animal pollinators
what is the function of the pistil?
produce the ovule
what is the function of the stamens?
pollen-bearing (produce sperm)
what is the receptacle?
location of flower stalk where the flower parts are attached
what is the peduncle?
the stem of a flower
what are complete flowers?
flowers with four main flower parts
what are incomplete flowers?
flowers that do not have all the four main flower parts
what are perfect flowers?
flowers with both male and female reproductive organs
what are imperfect flowers?
flowers that do not have both male and female reproductive organs
what is an advanatge of imperfect flowers? Why is it an advantage?
increase probability of outcrossing because they cannot self-pollinate. This increases genetic diversity
monocots have flower parts in multiples of
3’s
dicots have flower parts in multiples of
4’s or 5’s
what does the perianth consist of?
sepals and petals
what structural features of sepals help their function of protection?
- sclerenchyma
2. waxy cuticle
what is a hypanthium?
perianth fused into tube part way up, stamen filaments are sometimes included
what is the structure of stamens?
filaments holding pair of anther sacs
how are the anther sacs of wind-pollinated flowers attached to filaments?
at a single point
how are the anther sacs of animal-pollinated flowers attached to filaments?
along their length
what are the three parts of the pistil?
- ovary
- style
- stigma
what is the only part of the flower that is receptive to pollen?
stigma
what is a hypogynous flower? What ovary type is it?
other flower parts attach below the ovary. Superior ovary
what is an epigyous flower? What ovary type is it?
other flower parts attach above ovary. Inferior ovary
what is a perigynous flower? What is the ovary type?
perianth and stamens appear to attach above the ovary, but form a hypanthium that attaches below. 1/2 inferior ovary
what two cells are contained in the pollen grain?
- tube cell
2. generative cell
what is the function of the tube cell?
controls development of pollen tube, which penetrates and digests through stigma and style to ovule
what is the name of the opening in an ovule?
micropyle
what is the function of the generative cell?
follow tube cell down the tube, divide into two nuclei, one to fuse withegg to form diplod zygote, and other to fuse with diplod nucleus to form triploid endosperm
what is the K?
calyx, number of sepals
what is the C?
corolla, number of petals
what is the A?
androecium, number of stamens
what is the G?
gynoecium, number of carpels in ovary
what do brackets indicate in the floral formula?
fusion
how would you represent anthers fused into a ring in the floral formula?
curved line over the number of stamens
how is a hypanthium represented in the floral formula?
curved line underneath from K to A
how is an epigynous flower represented in the floral formula?
a hat above the G
what is regular floral symmetry, and what is the other name for it?
radial. Actinomorphic
what is irregular floral symmetry, and what is the other name for it?
bilateral. Zygomorphic
in some cultivars, the petals are actually
petaloid stamens
