PlantsPlants

B 3.3 Seed PlantsB 3.3 Seed Plants

Seed PlantsSeed Plants The seed plants generally are The seed plants generally are

classified into two major groups—classified into two major groups—gymnosperms (JIHM nuh spurmz) gymnosperms (JIHM nuh spurmz) and angiosperms (AN jee uh and angiosperms (AN jee uh spurmz). spurmz).

Leaves are the organs of the plant Leaves are the organs of the plant where the food-making process—where the food-making process—photosynthesis—usually occurs. photosynthesis—usually occurs.

Most leaves have small openings in Most leaves have small openings in the epidermis called stomata (STOH the epidermis called stomata (STOH muh tuh).muh tuh).

Stomata

Seed PlantsSeed Plants

Each stoma is surrounded by two Each stoma is surrounded by two guard cells that open and close guard cells that open and close it. it.

Materials move between leaves Materials move between leaves and roots through the vascular and roots through the vascular tissue in the stem. tissue in the stem.

Plant stems are either Plant stems are either herbaceous (hur BAY shuns) or herbaceous (hur BAY shuns) or woody.woody.

Seed PlantsSeed Plants Water and other substances enter a plant Water and other substances enter a plant

through its roots. through its roots. Roots can store food. When you eat carrots Roots can store food. When you eat carrots

or beets, you eat roots that contain stored or beets, you eat roots that contain stored food. food.

Xylem (ZI lum) tissue is made up of hollow, Xylem (ZI lum) tissue is made up of hollow, tubular cells that are stacked one on top of tubular cells that are stacked one on top of the other to form a structure called a vessel. the other to form a structure called a vessel.

Phloem (FLOH em) is a plant tissue also Phloem (FLOH em) is a plant tissue also made up of tubular cells that are stacked to made up of tubular cells that are stacked to form structures called tubes. Phloem help form structures called tubes. Phloem help move food.move food.

Seed PlantsSeed Plants

CambiumCambium (KAM bee um) is a tissue that (KAM bee um) is a tissue that produces most of the new xylem and phloem produces most of the new xylem and phloem cells. cells.

Gymnosperms Gymnosperms are vascular plants that are vascular plants that produce seeds that are not protected by fruitproduce seeds that are not protected by fruit

Four divisions of plants—conifers, cycads, Four divisions of plants—conifers, cycads, ginkgoes, and gnetophytesginkgoes, and gnetophytes (NE tuh fites)—(NE tuh fites)—are classified as gymnosperms. are classified as gymnosperms.

All conifers produce two types of cones—All conifers produce two types of cones—male and female.male and female.

Male Cone Female Cone

Seed PlantsSeed Plants

An angiosperm is a vascular An angiosperm is a vascular plant that flowers and produces plant that flowers and produces fruits with one or more seeds. fruits with one or more seeds.

A cotyledon is part of a seed A cotyledon is part of a seed often used for food storage. often used for food storage.

Monocots have one cotyledon Monocots have one cotyledon inside their seeds and dicots inside their seeds and dicots have two.have two.

Seed PlantsSeed Plants

If a plant's life cycle is completed If a plant's life cycle is completed within one year, it is called an within one year, it is called an annual. annual.

Plants called biennials (bi Eh nee Plants called biennials (bi Eh nee ulz) complete their life cycles ulz) complete their life cycles within two years. within two years.

Angiosperms that take more than Angiosperms that take more than two years to grow to maturity are two years to grow to maturity are called perennials.called perennials.

Annuals

Perennials

Seed PlantsSeed Plants

AngiospermAngiosperm GymnospermGymnosperm XylemXylem PhloemPhloem CambiumCambium CotyledonCotyledon Annuals and perennialsAnnuals and perennials