Introduction to Environmental and Agricultural Science

1
Introduction to Environmental and Agricultural
Science

• Plant Systems
• Plant Structures and Functions

2
Objectives

• Discuss the importance of plants.
• Identify the four main parts of a plant.
• Describe the many functions of roots, stems,
  leaves, and flowers.
• Explain the variations found in the root systems,
  stems, leaves and flowers.
• Describe the relationship of plant parts to
  fruit, nuts, and vegetables.

3
The Importance of Plants

• Plants are a basic part of the food chain.
• The Web of Life is dependent upon plants.
• Plants are the backbone of Agriculture.
• Animal Industry
• Feed for livestock and poultry
• Plant Industry
• Superior plants are needed for seed
• Horticulture Industry
• Plants are needed for seeds, cuttings, food for
  humans (fruits, nuts, vegetables), and
  landscaping.

4
Parts of the Plant

• Root
• Stem
• Leaf
• Flower

5
Roots

• 2 Main Functions
• 1. Absorb water nutrients
• from the soil
• 2. Anchor the plant
• Additional Functions and Uses
• Food storage (ex. Carrots, Sweet Potatoes,
  Beets, and Radishes)
• Asexual propagation (ex. Separation Division)

6
Types of Root Systems

• Fibrous

• Taproot

• Adventitious

7
Stems

• 2 Main Functions
• 1. Support the leaves, flowers, and fruit.
• 2. Transport water, nutrients, and manu-
• factured food within the plant.
• Additional Functions and Uses
• Food Storage (ex. Irish Potato and Onions)
• Asexual Propagation (ex. Cuttings, Grafting, and
  Separation)
• Livestock Feed (ex. Corn Stalks
• and Grass)

8
Types of Stems

• Aboveground Stems
• Woody
• Tough and winter hardy
• Herbaceous
• Succulent, often green, and
  will not survive
  cold winters
• Underground Stems
• Bulbs
• surrounded by scales (ex. Lilies and onions)
• Corms
• thickened, compact, and fleshy (ex. Gladiolus)
• Rhizomes
• horizontal stem (ex. Johnson Grass and Iris)
• Tubers
• thickened and store carbohydrates (ex. Irish
  Potato)

9
Leaves

• Food Factory for the Plant
• Leaf Arrangements help in identification.
• Alternate
• Opposite
• Whorled

Can you name the leaf arrangements?
10
Flowers

• Main Function Reproduction
• Additional Functions
• Beauty
• Fragrance
• Food (ex. Fruits, nuts and vegetables)

11
Parts of the Flower
Petal
Anther
Stigma
Stamen
Style
Pistil
Filament
Ovary
Sepal
Remember An incomplete or imperfect flower
has either the male or the female reproductive
organs, not both. ?
Complete or Perfect Flower
12
Functions of Each Flower Part
Flower Part
Function

• Stamen
• Petal
• Filament
• Style
• Ovules
• Ovary
• Pistil
• Sepal
• Stigma
• Anther
• Complete or Perfect Flower
• Incomplete or Im-perfect Flower

• The male part of the flower.
• The part of the flower, which attracts insects or
  other pollinators.
• The male part, which supports the anther.
• The tube that pollen travels down to fertilize
  the eggs.
• The eggs which are the female reproductive cells.
• Contains the eggs, and when fertilized enlarges
  into the fruit.
• The female part of the flower.
• The protective device for the developing flower.
• The female part that receives the pollen.
• Produces the pollen.
• A flower containing both male and female
  reproductive organs.
• A flower containing either male OR female
  reproductive organs, not both.

13
Fruits, Nuts, and Vegetables

• What is the difference?
• A fertilized seed develops into the pistil,
  enlarges, and becomes fruit.
• Nuts are really a type of fruit.
• Vegetables, however, can be any part of the plant
  root, stem, leaf, flower.