Chapter Twelve: Introduction to Plants
Section One: What is a Plant?
Vocabulary
Non-vascular Plant- the three groups of plants that lack specialized conducting tissues and true roots, stems, and leaves
Vascular plant- a plant that has specialized tissues that conduct materials from one part of the plant to another
Gymnosperm- a woody, vascular seed plant whose seeds are not enclosed by an ovary or fruit
Angiosperm- a flowering plant that produces seeds within a fruit
Chapter Twelve, Section One: Summary
Basic diagram of a plant's life.
Section one was about plant characteristics. A plant has to be able to photosynthesize, have cuticles, cell walls, and be able to reproduce. Plants use sunlight to make food form carbon dioxide and water. Plants have cuticles to protect them. Plants also have cell walls. Cell walls support and protect the plant. Plants have two stages in their life, the gametophyte and sporophyte stage. Plants make spores in the sporophyte stage. New plants are gametophyte. A fertilized egg from a plant grows into a sporophyte Plants are either vascular or non vascular. Vascular plants are either seedless, nonflowering seed, and flowering seed plants. Non flowering seed plants are gymnosperms. Flowering seed plants are angiosperms. Plants and green algae have similar characteristics, so scientists think they had a common ancestor.
Section Two: Seedless Plants
Vocabulary
Rhizoid- a rootlike structure in non-vascular plants taht holds th plants in place and helps plants get water and nutrients
Rhizome- a horizontal, underground stem that produces new leaves, shoots, and roots
Chapter Twelve, Section Two: Summary
Fern leaves in comparison to a violin end.
Section two was about non vascular and seedless vascular plants. Mosses, liverworts, and hornwarts are non-vascular plants. Mosses have rhizoids or a root like structure. Rhizoids help get water and nutrients to plants. Rhizoids also keep the plant in place. Liver and hornworts also have rhizoids. Ferns, horsetails and, club mosses are seedless vascular plants. Ferns have rhizomes. Rhizomes are where new leaves and roots grow. Fern leaves are called frond because they look like the end of a violin. Seedless vascular plants are used in everyday products.
Section Three: Seed Plants
Vocabulary
Pollen- the tiny granules that contain the the male gametophyte of seed plants
Pollination- the transfer of pollen from the male reproductive structure to the female structures of seed plants
Chapter Twelve, Section Three: Summary
Monocots' flowers part into three. Dicots' part into four or five.
Section three was about the structure of seed plants. Seed plants do not live independently of the sporophyte. Gametophytes of seed plants form within the sporophyte. Sperm of seed plants do not need water to reach the egg, unlike seedless plants. Sperm form with pollen. Seeds are made up of a sporophyte, stored food, and a seed coat. Food is stored in cotyledons. Gametophytes reproduce by cones. The male cone fertilizes the female cone. The seed develops inside the cone and is deposited. Angiosperms are the most common plant. Angiosperms spread their pollen by wind or, if they have flowers, by animals. Angiosperms are either dicots or monocots. Monocots have one cotyledon. Dicots have two cotyledons. Animals eat angiosperms. Humans also use angiosperms as food, clothing and medicine.
Section Four: Structure of Seed Plants
Vocabulary
Xylem- the type of tissue in vascular plants that provides support and conducts water and nutrients from the roots
Phloem- the tissue that conducts food in vascular plants
Sepal- in a flower, one of the outermost rings of modified leaves that protect the flower bud
Petal- one of the ring or rings of the usually brightly colored, leaf-shaped parts of a flower
Stamen- the male reproductive structure of a flower that produces pollen and consists of an anther at the tip of a filament
Pistil- the female reproductive part of a flower that produces seeds and consists of an ovary, style, and stigma
Ovary- in a flowering plants, the lower part of a pistil that produces eggs in ovules
Chapter Twelve, Section Four: Summary
The brown parts are the stamen and the middle part is the pistil.
Section four was about seed plant structures. Plants have xylem and phloem to transport water and food. Plants have roots to supply water, hold them in the soil, and to store surplus food. Roots have a cover called an epidermis. Roots have a root caps to protect the root tip. There are two kinds of roots, a taproot and and a fibrous root. Taproots grow downward and have many smaller roots. they get water deep underground. Dicots and gymnosperms have taproots. Fibrous roots have several roots that are about the same size. They get water from the surface of the soil. Monocots have fibrous roots. Plants also have stems. Stems support the plant, transport materials, and store materials. Soft, thin, flexible stems are called herbaceous stems. Rigid stems made of wood and bark are called woody stems. A ring of dark cells and a ring of light cells is a growth ring. Leaves make food for plants. Leaves have many layers. Photosynthesis takes place in the middle layers. Some leaves have adapted, like cacti. Flowers are used for sexual reproduction. They produce nectar to attract insects. Sepals protect the bud, when the flower blooms the sepal folds back. Petals are used to attract insects, the insects transport pollen to other flower. Stamens are male reproductive structures. Stamens have filaments that are topped with anthers structures that contain pollen. Pistils are female reproductive structures. The top of the pistil is called the stigma. Pistils have ovaries that contain ovules. Humans use flowers for many reasons, such as cooking.