7Th Gr Science-From Bacteria To Plants Ch 5 Sec 1

Front 1

Seed Plants

Back 1

Plants that have vascular tissue and use seeds to reproduce. Most seed plants live on land. Examples include rice, tomatoes, peas, and squash.

Front 2

Phloem

Back 2

The vascular tissue through which food moves. Food is made in a plant's leaves, enters the phloem, and travels to the plant's stems and roots.

Front 3

Xylem

Back 3

The vascular tissue through which water and nutrients travel in some plants. The plant's roots absorb water and nutrients from the soil. These materials enter the root's xylem and move upward into the plant's stems and leaves.

Front 4

Seeds

Back 4

Structures that contain a young plant inside a protective covering. After sperm cells fertilize the eggs, seeds develop and protect the young plant from drying out. A seed has three important parts-an embryo, stored food, and a seed coat.

Front 5

Embryo

Back 5

A young plant that develops from the zygote, or fertilized egg. It already has the beginnings of roots, stems, and leaves.

Front 6

Cotyledons

Back 6

A seed leaf that stores food.

Front 7

Seed Coat

Back 7

The outer covering of a seed. Examples are skins on lima beans, peanuts, and peas. Seed coats act like plastic wrap, protecting the embryo and its food from drying out. This allows a seed to remain inactive for a long time.

Front 8

Seed Dispersal

Back 8

The scattering of seeds. This can be done by animals (through their waste or by the animal's transport of the seeds on it's fur), through water transport, or by the wind.

Front 9

Germination

Back 9

The early growth stage of an embryo. Germination begins when the seed absorbs water from the environment. Then the embryo uses its stored food to begin to grow. First, the embryo's roots grow downward, then its leaves and stem grow upward.

Front 10

Leaves

Back 10

Leaves capture the sun's energy and carry out the food-making process of photosynthesis.

Front 11

Stomata

Back 11

Small openings or pores that open and close to control when gases enter and leave the leaf. When the stomata are open, carbon Dioxide enters the leaf and oxygen and water vapor exit.
Stomata often close when the temperature is very hot, allowing the plant to slow down transpiration.

Front 12

Chloroplasts

Back 12

Chloroplasts are structures in plants that look like green jelly beans, in which food is made. Photosynthesis occurs in the chloroplasts of plant cells. The cells that contain the most chloroplasts are located near the leaf's upper surface, where they are exposed to the sun. The chlorophyll in the chloroplasts traps the sun's energy.

Front 13

The Leaf and Photosynthesis

Back 13

Carbon dioxide enters the leaf through open stomata. Water, which is absorbed by the plant's roots, travels up the stem to the leaf through the xylem. During photosynthesis, sugar and oxygen are produced from the carbon dioxide and water. Oxygen passes out of the leaf through the open stomata. The sugar enters the phloem and then travels throughout the plant.

Front 14

Cuticle

Back 14

A waxy, waterproof coating that coats the leaf's upper surface.

Front 15

Upper Leaf Cells

Back 15

The upper leaf cells contain chloroplasts that trap the energy in sunlight for photosynthesis.

Front 16

Lower Leaf Cells

Back 16

The many spaces between the lower leaf cells temporarily store carbon dioxide and oxygen.

Front 17

Transpiration

Back 17

The process by which water evaporates from plant's leaves.

Front 18

Stem

Back 18

The stem of a plant carries substances between the plant's roots and leaves. The stem also provides support for the plant and holds up the leaves so they are exposed to the sun. In some plants, the stem also stores food.

Front 19

Stem Types

Back 19

1) Herbaceous-these stems are soft-examples are dandelions, dahlias, peppers, and tomato plants.
2) Woody-these stems are hard and rigid-examples are maple trees, pine trees, and roses. Woody stems have an outer layer of material called "bark" for protection and support.

Front 20

Cambium

Back 20

The layer of cells in a plant that produces new phloem and xylem cells.

Front 21

Annual Rings

Back 21

The pattern of circles in a tree stump like looks like a target. They each represent one year of a tree's growth. These rings are made up of xylem. In the spring wide, light brown rings are formed. In the summer the rings formed are thin and dark. One pair of light and dark rings represent one year's growth.

Front 22

Roots

Back 22

Roots anchor a plant in the ground and absorb water and nutrients from the soil.

Front 23

Types of Roots

Back 23

1) Taproot-consists of a long, thick main root with thin, branching roots growing off the main root (turnips, radishes, dandelions, cacti)
2) Fibrous-consists of several main roots that branch repeatedly to form a tangled mass (lawn grass, corn, most trees)

Front 24

Root Cap

Back 24

The root cap contains dead cells and protects the root from injury from rocks and other material as the root grows through the soil.

Front 25

Root Hairs

Back 25

Root hairs grow out of the root's surface. They increase the surface area of the root that touches the soil. This allows more water and nutrients to be absorbed. The roots also help to anchor the plant.