Seedless Plants Nonvascular Seedless Plants • • • • • Mosses, liverworts, hornworts Grow on soil, bark of trees, rocks Usually live in places that are damp Are very small Each cell of the plant must get water from the environment • Some have a rhizoid, a rootlike structure that helps the plant hold itself in place Seedless Vascular Plants • Ferns, horsetails, club mosses • These plants have vascular tissues that specialize in moving nutrients around the plant • Some of these plants have a rhizome, an underground stem from which new leaves and roots grow Life cycle of Seedless Plants • Sporophytes release spores into air • Spores grow into male and female gametophytes • Sperm from male plants swims through water to fertilize eggs • Eggs grow into sporophyte and the process repeats • Water is necessary in the lifecycle of this type of plant Seed Plants • The two groups of vascular seed plants are the gymnosperms and the angiosperms • Gymnosperms do not have flowers or fruit • Angiosperms have flowers and seeds that are protected by fruit Characteristics of Seed Plants • Produce seeds. Seeds nourish and protect young sporophytes • Gametophytes and sporophytes do not live independently of each other. Gametophytes from within the reproductive structures of the sporophyte • Sperm from seed plants is protected and forms inside pollen. Pollen can be carried by animals or the wind • Seed plants can live just about anywhere and are the most common plants on Earth today Structure of Seeds • Seeds form after fertilization • Seed has three parts, sporophyte, stored food or cotyledons, seed coat that surrounds and protects young plant Gymnosperms Life Cycle • Evergreens or cone bearing plants and trees • Seed contains a young sporophyte which grows into an adult sporophyte • Spores are produced and they grow into gametophytes • Females gametophytes produced eggs and male gametophytes produce sperm in pollen • Wind or insects carry pollen to eggs. • Fertilized egg develop into a seed that contains a sporophyte Angiosperms • Vascular flowering plants that produce flowers and fruit • Angiosperms use flowers and fruit to attract insects and animals to help spread pollen to eggs