anther The pollen-containing structure in a flower.
calyx The sepals collectively; outermost layer of the flower.
carpel “Female” portion of the flower; consists of stigma, style, and ovary.
complete flowers Flowers that contain all four structures: sepals, petals, stamens, and
one or more carpels.
conifers Group of gymnosperms that bear cones; includes spruces, pine, and fir trees.
corolla The petals of a flower collectively are known as the corolla.
dormant Halting growth and development temporarily.
ginkgo Tree known as the “living fossil” because it is the only species left in the phylum
Ginkgophyta.
gnetophytes Diverse group of gymnosperms that includes Ephedra and Welwitschia.
gymnosperms Seed plants in which the seeds are not encased in a fruit.
incomplete flowers Flowers that are missing one or more structures: sepals, petals, sta-
mens, or carpels.
ovary Enlarged part of the carpel where the ovules are contained.
sepals Outermost layer of the flower that is usually leaf-like and green.
stamens The part of the flower consisting of a filament and an anther that produces pollen.
stigma The knoblike section of the carpel where the pollen must land for fertilization to
occur.
Points to Consider
- Do you think plants can sense their environment? Why or why not?
- Can you think of an example of a hormone?
- Do you think that plants have hormones?
- How do you think trees know when it’s time to lose their leaves?