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Section 24-1: Reproduction With Cones and Flowers
Reproduction in gymnosperms takes place in cones, which are produced by a mature sporophyte plant.
Flowers are reproductive organs that are composed of four kinds of specialized leaves: sepals, petals, stamens, and carpels.
Reproduction in angiosperms takes place within the flower. Following pollination and fertilization, the seeds develop inside protective structures called fruits.
Most gymnosperms are wind pollinated, whereas most flowering plants are pollinated by animals.
Section 24-2: Seed Development and Germination
As angiosperm seeds mature, the ovary walls thicken to form a fruit that encloses the developing seeds.
Seeds dispersed by animals are typically contained in fleshy, nutritious fruits.
Seeds dispersed by wind or water are typically lightweight, allowing them to be carried in the air or to float on the surface of the water.
Environmental factors such as temperature and moisture can cause a seed to end dormancy and germinate.
Section 24-3: Plant Propagation and Agriculture
Vegetative reproduction includes the production of new plants from horizontal stems, cuttings, leaves, plantlets, and underground roots.
Horticulturists use plant propagation to make many identical copies of a plant or to produce offspring from seedless plants.
Most of the people of the world depend on a few crop plants, such as wheat, rice, and corn, for the bulk of their food supply.