The Plant Structure

By : Chris Ban

Science Presentation

The Plant

This is a diagram of a plant.

Plants are made up of roots, the stem, the leaf, and the flower.

In this presentation I will explain each part more thoroughly.

The Root

Roots are actually a lot stronger than they seem

They can buckle sidewalks

Break apart solid rock. They can also grow to be

very long. The longest grown was 1200m. (400ft.) by a fig tree in South Africa.

Xylem, and Phloem

There are two types of vascular tissue: Xylem, and Phloem.

Xylem- is located at the center of the root, and transports water, and minerals to plant. (bottom)

Phloem-transports products of the photosynthesis, or food to the plant. It is located around the Xylem. (top)

The Stem

• Food-Storage tissue is located inside of the vascular tissue. It is made up of loosely packed cells that store food.

• Growth Tissue- is made up of the cambium and is located between the xylem and phloem. This thin layer produces new xylem tissue to the inside and new phloem tissue to the outside.

• Protective Tissue is found outside the storage tissue and forms the outer covering of the stem.

• The stem includes the vascular tissue with xylem and phloem just like the root.

Other stems

• The arrangement of the tissues in the stem depends on the type of stem. Dicot and monocot stems differ in their arrangement of vascular tissue. Woody stems and herbaceous stems, usually green and flexible, have vascular tissue arranged in groups called vascular bundles.

(picture of herbaceous stem)

Other Stems Woody stems are harder

and more rigid than herbaceous stems. In plants that have woody stems, the xylem is organized in a series of annual rings. The outermost ring is the bark. The bark contains cork; the inner bark contains both dead and living phloem cells.

The Leaf• The leaf includes the vein, the

blade,and the petiole.• On the lower surface of most

leaves are small openings called stomata.

• As the cells that make up the sides of the stomata take in water, they swell and fit tightly together preventing leaks.

• The cells that make up the sides of the stomata are called guard cells. Carbon-dioxide passes into the leaf. Water vapor and oxygen pass out through these small openings.

• Epidermal tissue protects the inside of the leaf from injury or disease.

• In some plants there is extra protection provided by a waxy cuticle layer that covers the epidermis.

Palisade Cells

• Inside the leaf are 2 more layers. The upper layer is made of palisade cells, and Spongy cells.

• Palisade cells-are-Elongated cells stacked closely together. They make the most food for the plant and provide support for the leaf

Spongy Cells

• These cells make it easy for carbon-dioxide, and oxygen to move through the leaf tissue.

(Chloroplasts in living spongy mesophyll cells of Impatiens.-picture right )

A leaf cell diagram

• 1.  Cuticle• 2.  Epidermis• 3.  Palisade Layer• 4.  Spongy Mesophyl• 5.  Guard Cells

   

The Flower• Sepals-The outermost part of the flower.

It is collectively known as the calyx.

• Petals-Inside the calyx. Surrounds the reproductive parts, attract insects and other animals for pollination. Collectively known as the corolla.

• Stamens- The male part of the flower located inside the petals. Made of a stalk called the filament. Attached to the top of the filament is the anther, a sac that holds the pollen, which contains the sperm cells.

• Pistils-The female part of the plant located in the center of the flower. Made of a slender tube called the style;at the top of the style is a sticky structure called the stigma; at the base of the style is the ovary, which contains the ovules, which will develop into seeds.

Complete and incomplete

Many flowers have all four flower parts present; some have one or more missing parts.

Flowers that have all four parts are called complete flowers.

Flowers that lack one or more parts of the flower are called incomplete flowers.

Flowers are either perfect or imperfect. Perfect flowers have both stamen or pi and pistils. Imperfect flowers are either male or female and lack pistils

or stamens

Seeds

• The structure diagrammed on the right is an ovule and will develop into a seed. The integument will become the seed coat.

• The cotyledon is a seed leaf. In monocots only one cotyledon is present. In dicots two cotyledons are present.

• The embryo is in plant seeds, it is the young plant.

Fruits

• Seeds in a pod (left)• After fertilization has

occurred, it develops into a fruit. Fruits may be fleshy, hard, multiple or single. Seeds germinate, and the embryo grows into the next generation -sporophyte.

• The fruit is a structure that develops from the ovary after fertilization. It contains the seeds and protects them from disease and animals.

• The seed coat is the protective coat the forms the outer covering of the seed and helps protect inner parts of the seed

Sources

• Ritterskamp, Ronald. Explore God’s Creation. Pacific Press Publishing Assoc., 1995.