Plants Part 2

Growth andReproduction

Plant growth

• Many plants have continuous growth

• Growth occurs in discrete places

• Primary growth is the making of new tissues

• Secondary growth is the enlarging of older tissues

Only dicots have secondary growthWood is a type of secondary growth and occurs along the vascular cambium

Rings are made when wood produced in the spring meets wood produced in the winter

Reproduction• Asexual

– Rhizomes (iris)– Bulbs or corms (daffodils)– Runners or stolons (Bermuda grass,

strawberries)

• Sexual– Spores (mosses, liverworts and ferns)– Seeds (gymnosperms, and angiosperms)

1) Stamen male reproductive parts– Anther contains pollen– Filament stem-like portion of the stamen that holds the anther

erect

2) Carpel female reproductive parts of the flower– Stigma sticky end part of the carpel fo pollen attachment– Style the stalk that raises the stigma out of the flower– Ovary area in which the ovules are kept ovary wall will

develop into fruit

3) Ovule structure that will develop into seed after fertilization

4) Calyx outer most portion of the flower, usually showy– Petals usually the colorful portion of the flower

collectively the petals are called the corrolla– Sepals outermost part of the flower covers the

developing bud often green, but sometimes colored like the petals as in lillies

What is a fruit?

• A mature ovary

• Found only in angiosperms

• Protects the seeds by enlarging the ovary wall

• Aids in dispersal of seeds